Fuel Delivery: TPI to Carb Conversion

[88WS-6]

I did not do this swap, I am merely dealing with the aftermath. First step is to figure out what exactly was done, then I will move into the problem solving phase. If possible, I'd like to just use the stock in-tank pump with a Mallory 4309 AFPR and hook everything up correctly.

Pictures of the current set-up in the engine bay:

http://www.fquick.com/images/vehicles/full/41137360713.jpg?1329243328

http://www.fquick.com/images/vehicles/full/41137360714.jpg?1329243331




A few pictures of a successful Mallory 4309 AFPR install (thanks to LilJayV10 at thirdgen.org for the pics)

http://i192.photobucket.com/albums/z185/LilJayV10/DSC00188-1.jpg

http://i192.photobucket.com/albums/z185/LilJayV10/DSC00189-1.jpg

http://i192.photobucket.com/albums/z185/LilJayV10/DSC00184.jpg


A few things to note:
The previous owner said he disconnected the stock TPI in-tank pump, but it is still there. He also installed a Holley (blue?) pump just before the rear axle (i'll get some pics this afternoon). Phil's eagle eye spotted a mechanical pump on the block so basically... WTF.

Mallory 4309 install thread here:

http://www.thirdgen.org/techboard/carburetors/492155-pics-mallory-4309-installed.html




I'll take some more pics under the hood when I get home as well.

~Matt

[BonzoHansen]

why not just use a mechanical f/p for the carb? Simple, reliable, cheap.

[88WS-6]

Well I may go that route, but apparently it was attempted already. It may be running off that now, although I just found out it was even there. Before I think about the solution I'm going to try to figure out what is working/not working as it sits.

Also, I tend to do things backwards and in ways that cost more money in the end for no particular reason, so try to work with me here.

[sweetbmxrider]

Well you want it to be reliable since it was cutting out on the highway, the car has 3 fuel pumps (I should look into this), and who doesn't like inexpensive?

Mechanical fuel pump or hit your head with a hammer until it makes sense.

[BonzoHansen]

Before I think about the solution I'm going to try to figure out what is working/not working as it sits.

Good call. I think you might need to determine where you actually stand now. Then go from there. But that feed line sure looks like it heads to the pump on the block.

http://www.fquick.com/images/vehicles/full/41137360713.jpg

Based on what I have read so far, like those electric fans on a manual switch that HVAC setup, and your comments on the fuel system, I might make WAG that you may have a lot of room for improvement/optimization by simply backing up and doing somethings right, nodding towards the KISS principle when possible. Don't over complicate a simple setup.

Just my $0.02. BTDT, lived to tell the tale.

[WildBillyT]

Good call. I think you might need to determine where you actually stand now. Then go from there. But that feed line sure looks like it heads to the pump on the block.

http://www.fquick.com/images/vehicles/full/41137360713.jpg

Based on what I have read so far, like those electric fans on a manual switch that HVAC setup, and your comments on the fuel system, I might make WAG that you may have a lot of room for improvement/optimization by simply backing up and doing somethings right, nodding towards the KISS principle when possible. Don't over complicate a simple setup.

Just my $0.02. BTDT, lived to tell the tale.

Yup. I run a mech pump on my Nova for that reason. Much less to fail, and it's not a race car so what's a few hp. No regulator required.

Also, regardless of setup you should have a fuel filter as the last thing in the line before the carb. And definetly get a double throttle return spring.

[BonzoHansen]

and I wouldn't blindly put your running issues all on fuel. A lot of "fuel" problems are ignition problems.

[88WS-6]

the car has 3 fuel pumps (I should look into this)

Shouldn't it run 3 times more awesome then? :bertstare:

[88WS-6]

and I wouldn't blindly put your running issues all on fuel. A lot of "fuel" problems are ignition problems.

From what I can tell it's a brand new Accel vaccum HEI distributor, cap and rotor. He said plugs and wires too, but we'll see...


Oh and the Crane ignition box but I'm not sure if that was used when he installed it. I think the dryer hose on the heater box underneath it was used though.

[BonzoHansen]

ha ha ha i had a world of trouble with an accell dizzy I had to buy in a pinch. just last spring

add: oh yeah, my problems sounded kind of like yours, acted up after it got hot.

[88WS-6]

This should work well:
http://www.summitracing.com/parts/CRT-M6626/

That pump has a regulator inside of it.

[88WS-6]

I was also just reading that, at least in 87, the LG4 had an electric in-tank pump and a mechanical pump on the block. I'll try to confirm that, but WTF?

It is apparently also better to keep the in-tank electric pump and use a regulator at the carb so that you can return the excess fuel and not have a "dead head" pump. Does that make sense?

[BonzoHansen]

the first one is a basic stock replacement. might be the same one I have in the 77. note that one has a return line.

some 3rd gens did get some kind of helper pump IIRC but I know not why.

[//<86TA>\\]

the helper pump was for vapor lock issues i believe.

if the car is to stay carbed, the tank needs to be removed, whatever pump setup is in there needs to be removed and bypassed. After that, a mechanical pump will be fine, so long as the fuel lines are well insulated, especially if the mechanical pump has no return line. Or keep the ghetto electric pump and ditch the mechanical pump, but you still should have a return line.

You should also look into what happened to the fuel hardlines. They should be on the driverside, they are not visible in the pics, so where are they? Hopefully there is not 15' of rubber hose running under the car.

[The Fixer]

Are you sure the car was an LB9 car to start off, and not an L69? They did still have carb'd F-bodies in '87. Have you found the electric harness running to the tank? If it's only a single wire back there, it was carb'd originally. The EFI cars have a 3-wire connector at the tank (gauge sender, power for f/p, and ground).



if the car is to stay carbed, the tank needs to be removed, whatever pump setup is in there needs to be removed and bypassed. After that, a mechanical pump will be fine, so long as the fuel lines are well insulated, especially if the mechanical pump has no return line. Or keep the ghetto electric pump and ditch the mechanical pump, but you still should have a return line.

You should also look into what happened to the fuel hardlines. They should be on the driverside, they are not visible in the pics, so where are they? Hopefully there is not 15' of rubber hose running under the car.

:werd: Just to continue this thought, the easiest way to bypass an OEM in-tank pump would be to get a new tank sending unit for an '84 F-body with L69 (carb motor). It'll just have a pickup tube with a screen and a new float for the gauge.

[88WS-6]

I have the build sheet and SPID and both confirm its a factory LB9 TPI car. I called the original owner today and he said that he already removed the in-tank pump. The wires may still be there. He put in an electric pump in front of the rear axle but it burnt out. So he finally installed the mechanical fuel pump which is on the block and currently feeding the carb. I took pics and got a replacement phone today so ill post them tomorrow from work

[88WS-6]

Ok here we go:

Mechanical fuel pump:
http://www.fquick.com/images/vehicles/full/41137360790.jpg?1329392490

Throttle linkage:
http://www.fquick.com/images/vehicles/full/41137360788.jpg?1329392465

Passenger-side of the carb:
http://www.fquick.com/images/vehicles/full/41137360789.jpg?1329392478

Fuel lines:
http://www.fquick.com/images/vehicles/full/41137360792.jpg?1329392518

Holley electric fuel pump:
http://www.fquick.com/images/vehicles/full/41137360793.jpg?1329392532

From the back:
http://www.fquick.com/images/vehicles/full/41137360795.jpg?1329392554

Back of the fuel pump again:
http://www.fquick.com/images/vehicles/full/41137360796.jpg?1329392565

And a little higher up this time:
http://www.fquick.com/images/vehicles/full/41137360797.jpg?1329392575

One more:
http://www.fquick.com/images/vehicles/full/41137360798.jpg?1329392587


This was also a major pain because the car is very low. Stock IROC springs with 3/4 coil out of the front and 1/2 coil out of the back. Maybe an inch of ground clearance at the nose.

http://www.fquick.com/images/vehicles/full/41137360799.jpg?1329392600

The previous owner also said last night that there is access to the electric Holley pump from the driver-side back seat. I didn't look, but I'm assuming he cut a hole in the floor... He mentioned that it's all wired up but he removed the fuse from that area after it burnt out. I'll pull up the carpet later today and get some more pics. He also said that the mechanical pump is not wired exactly the way he would have wanted, because he was running out of the 6AN line so he did what he could :facepalm:


Let me know if you'd like to see any other areas better. I wanted to take some more pics of the fuel lines in the engine bay but its just way too low to get under there without a jack.

~Matt

[sweetbmxrider]

Is the braided line really worm clamped?

Son, you have work.

I wouldn't be surprised if the fuse blew because he sucked at wiring and/or it rubbed through on the body somewhere.

[LTb1ow]

Sheet metal screws holding up the fuel lines? Legit! But hell, at least they aren't copper!

[88WS-6]

Well at least I keep it real

[LTb1ow]

That you do, driving that thing is prob very close to life threatening :lol:

If you have the time, I would start pulling it all and then reinstall what you need. And with any hope you install it bettter that guy did.

[BonzoHansen]

these sure look like low pressure power steering lines unless the photo angle is deceiving
http://www.fquick.com/images/vehicles/full/41137360792.jpg

[88WS-6]

these sure look like low pressure power steering lines unless the photo angle is deceiving

Listen, I'm a driver not a thinker. They very well could be steering lines, although they run in front of the rad over to the mech fuel pump.

[sweetbmxrider]

They clearly attach to the power steering box and pump.

I'm betting the fuel lines go under the oil pan towards the driver floor.

[WildBillyT]

In the last pic those are power steering lines.


That is without question the worst Holley Blue installation I've ever seen. Starting from the tank and working forward:

1.) That's the wrong kind of fuel filter between the sending unit and the pump. A coarser filter goes back there (like a Fram HPG1) and fine filter goes up by the carb.

2.) I have never seen somebody mount a Holley pump like this in any way but straight up and down. Horizontal is just asking for trouble and it may have air issues. I'd bet that the motor itself is full of fuel.

3.) Can't tell from the pics, but it's probably not on a relay and the wiring is probably too small.

[88WS-6]

In the last pic those are power steering lines.


That is without question the worst Holley Blue installation I've ever seen. Starting from the tank and working forward:

1.) That's the wrong kind of fuel filter between the sending unit and the pump. A coarser filter goes back there (like a Fram HPG1) and fine filter goes up by the carb.

2.) I have never seen somebody mount a Holley pump like this in any way but straight up and down. Horizontal is just asking for trouble and it may have air issues. I'd bet that the motor itself is full of fuel.

3.) Can't tell from the pics, but it's probably not on a relay and the wiring is probably too small.


You're welcome. And trust me, I know how to find them.

[WildBillyT]

You're welcome. And trust me, I know how to find them.

Trust me, I have found ringers myself. Like an 18" rocker panel hole that was fiberglassed over.

On a good note that's all pretty easy to fix.

[88WS-6]

Well I could remove the electric pump and incorrect filters and just use the mech pump on the block. I'll have to see if I can get a part # off it to see what it is and if it has a regulator internally. I also need to see exactly what is running to and from it and if it has a return line.

[WildBillyT]

Well I could remove the electric pump and incorrect filters and just use the mech pump on the block. I'll have to see if I can get a part # off it to see what it is and if it has a regulator internally. I also need to see exactly what is running to and from it and if it has a return line.

That would be your best bet IMO.

[BonzoHansen]

gonna need a filter between the mech pump and the carb

[WildBillyT]

Listen, I'm a driver not a thinker. They very well could be steering lines, although they run in front of the rad over to the mech fuel pump.

One of those could very well be a return line back to the tank. It looks like there's a h@x0r return line near your Holley Blue.

[88WS-6]

gonna need a filter between the mech pump and the carb

Roger that.

[V]

one other quick side question.... when the stock in-tank pump was removed, was the pickup tube extended to actually reach further down into the tank or just left without the pump attached? if it was just left, you may have starvation issues due to that also.

[BonzoHansen]

I still think he has ignition issues....

Maybe we can find some time in a few weeks to come look.

[88WS-6]

This is behind the driver's seat. It looks like he accessed it through a drain-cap thankfully and did not cut a hole in the floor:

http://www.fquick.com/images/vehicles/full/41137361100.jpg?1329741564

The electrical tape is around the cap in the picture.



This looks like where the wiring harness was cut:

http://www.fquick.com/images/vehicles/full/41137361101.jpg?1329741577


Another shot of the mech fuel pump. Hard to see because of the shady, green wire to the battery in the foreground, but there is one line in and one line out of the pump:

http://www.fquick.com/images/vehicles/full/41137361102.jpg?1329741592


This shot shows the line running from the mech pump, under the water pump and block to the red/blue fitting in the picture. Fuel feed line I'm assuming:

http://www.fquick.com/images/vehicles/full/41137361103.jpg?1329741605


This part got tough. Dead center in this pic, just under the firewall, the shiny part behind the power steering arm(?):

http://www.fquick.com/images/vehicles/full/41137361104.jpg?1329741621

Another shot of the same part. I was practically mounting the radiator at this point:

http://www.fquick.com/images/vehicles/full/41137361105.jpg?1329741635

One last shot of it. I'm assuming it's a regulator? The line to the pump, with the red/blue, fitting attaches here. Then heads under the car:

http://www.fquick.com/images/vehicles/full/41137361099.jpg?1329741548



So from what I can see there is a line from the tank to the Holley blue pump in front of the rear axle. Then a line under the car to just under the firewall where that regulator(?) is in the last few pics. Then from there it goes to the red/blue fitting just in front of the engine block and then from there to the fuel pump. Then there is a separate line from the mech fuel pump on the block up and in between the block and engine accessories to the carb (pic below of the end).

http://www.fquick.com/images/vehicles/full/41137360714.jpg?1329243331

[The Fixer]

Pictures like that cut wiring harness make me cry. If you're going to stay carb, you might as well remove all the stuff going to the computer and clean up the previous owners mess. I'm pretty sure that tan wire by the hole in the floor was the power to the OEM fuel pump. You'll need to trace that mess as well.


Wow, I hate butchers.

[88WS-6]

Yea I really need to get under this thing but no jack + gravel driveway = not gonna happen.

[WildBillyT]

That silver thing looks like a fuel filter. It is not a regulator, or at least the one that comes with a Holley Blue.

If that fuel filter is that close to an exhaust manifold I wonder if you are heating your fuel.

[BonzoHansen]

what a mess. yes, that looks like a filter.

[88WS-6]

what a mess. yes, that looks like a filter.

Which I can re-use, only in a location just before the carb right? I don't know why he would put it there. I can barely see it, let alone get to it. He did mention that he was running out of fuel line, so I'm guessing this was one of the results of that...

[WildBillyT]

Which I can re-use, only in a location just before the carb right? I don't know why he would put it there. I can barely see it, let alone get to it. He did mention that he was running out of fuel line, so I'm guessing this was one of the results of that...

They are cheap, just replace it.





admin note: registration discussion moved to here: http://www.njfboa.org/forums/showthread.php?t=59047 BH-

[88WS-6]

What would be a good quality mechanical pump that I can install with a return line to the tank? I found a stock replacement Bosch pump from Rock Auto. It's the pump from the 87 LG4 cars I think, Bosch #68501. Is the vapor return line the same as a tank return line or is that for the charcoal canister?

I found a replacement in-tank pump, but I think it makes more sense to use a mechanical one on the block for now.

http://www.autozone.com/autozone/parts/Spectra-Premium-Fuel-Pump/1987-Chevrolet-Camaro/_/N-iieqqZ8vcz2?itemIdentifier=191411_173883_4967_

[BonzoHansen]

what is wrong with the one you have now?

[LTb1ow]

what is wrong with the one you have now?

Seeing the rest of the hack job, I would deem its performance questionable at best.

But thats me.

[88WS-6]

It only has an input and output line with no return line to the tank or vapor line (is there a difference?). I'd like to find one that has this.

[BonzoHansen]

Why? Most don't. however a nice stock replacement pump should be fine for this. I think if you look up most any 2nd gen with ac you'll find a pump with a return feed. My 77z has one.

Is there a return line back to the tank now to attach it to?

If this was my car i'd start with known issues before buying parts on a whim. But that's just me, I'm cheap. I think you are going to spend a few bucks just un rigging stuff.

[sweetbmxrider]

Ls1 corvette fuel filters have the return built into it but its operating pressure is much higher than yours.

[BonzoHansen]

Carb setups are simple. Do not complicate it.

[sweetbmxrider]

Well you're no fun :|

[WildBillyT]

Is there a return line back to the tank now to attach it to?



Find this out first.

[88WS-6]

My guess is that it was removed, but I'd have to look.

[BonzoHansen]

I wouldn't worry too much about that yet.

[88WS-6]

Went to my parent's house yesterday to pick up my new seats. I installed the passenger seat and when I went to leave the car wouldn't fire up. It had plenty of power and the starter was cranking the motor, but sounded like no fuel. I got it going after 4 or 5 tries but it would only stay running if I was on the throttle. I got 4 or 5 streets out and the first time I popped it into neutral it died and wouldn't start back up. Definitely seems fuel related to me. There is no hesitation or misfiring and no bucking. As soon as my foot comes off the gas it immediately dies, it doesn't even come down slightly.

I got AAA'ed to my mechanic so best case scenario I pay an hour of labor for him to diagnose it. He won't do any work on it because it's not factory anymore.


Side note: Don't ever try to get on and/or off a flat bed with cut springs.

[chrisfrom nj]

why dont you get a tpi wireing harness and convert the car back to tpi

[WildBillyT]

Went to my parent's house yesterday to pick up my new seats. I installed the passenger seat and when I went to leave the car wouldn't fire up. It had plenty of power and the starter was cranking the motor, but sounded like no fuel. I got it going after 4 or 5 tries but it would only stay running if I was on the throttle. I got 4 or 5 streets out and the first time I popped it into neutral it died and wouldn't start back up. Definitely seems fuel related to me. There is no hesitation or misfiring and no bucking. As soon as my foot comes off the gas it immediately dies, it doesn't even come down slightly.

I got AAA'ed to my mechanic so best case scenario I pay an hour of labor for him to diagnose it. He won't do any work on it because it's not factory anymore.


Side note: Don't ever try to get on and/or off a flat bed with cut springs.

Yes, it does sound like a fuel issue, but it could be a bad carb setting as well.

[BonzoHansen]

or choke issue

[WildBillyT]

or choke issue

Looks open in the pics of it running but yea, you never know.

I wonder how the system is vented, too. If it's all plugged up and doesn't have a vented gas cap that could be bad.

[88WS-6]

Looks open in the pics of it running but yea, you never know.

I wonder how the system is vented, too. If it's all plugged up and doesn't have a vented gas cap that could be bad.

From what I can tell there is no venting at all. No charcoal canister either.

My mechanic said, "sorry man, I don't even know where to start..."

:bertstare:

After work I'll see if I can get it home.

[88WS-6]

why dont you get a tpi wireing harness and convert the car back to tpi

Previous owner yanked the in-tank pump and I think the factory fuel lines so I'd need those too.

[88WS-6]

I just remembered that the previous owner said he couldn't install a thermostat because the stock TPI waterneck wouldn't work with the new set-up he threw together. He said he put the t-stat in the center console so I'll have to see if it's in there. He said he was just running it and manually using the fans on and off...

Would this affect the carb's choke at operating temp? The car runs really well on cold starts and but I'm thinking that when it needs to switch cycles this fuel issue starts.

[PolarBear]

What year is this car? I have a mostly complete TPI from an 88 GTA that I have no need for. Have harness and everything. All you would need are fuel lines and new pump in tank

[88WS-6]

87. I have the stock TPI and the entire set-up on my 88 GTA too. I just wanted to get this car running correctly as-is because I figured that would be the cheapest option. Now I'm not so sure...

[BonzoHansen]

if you put tpi back on then you have to worry about the cam, etc, not jiving with the tpi.

you have the basics already. it just needs to be fixed

[88WS-6]

if you put tpi back on then you have to worry about the cam, etc, not jiving with the tpi.

you have the basics already. it just needs to be fixed

Stock long block. He only changed the intake manifold, carb and distributor. And I have the originals (for sale).

[chrisfrom nj]

put all the stock tpi set up on get the tank and fuel pump and make it easy on you make the car stock again and you dnt have to worry about anything

[PolarBear]

87. I have the stock TPI and the entire set-up on my 88 GTA too. I just wanted to get this car running correctly as-is because I figured that would be the cheapest option. Now I'm not so sure...

Stock long block. He only changed the intake manifold, carb and distributor. And I have the originals (for sale).

Well you really need a harness now :-? Just an offer.

Since the engine wasnt really changed going back to TPI wouldnt be that bad, but it is up to you what you want to do.

[88WS-6]

What I would love is to have the car original with nothing cut and TPI on it. I would take you up on that harness in a heartbeat and put TPI back on, but it needs to be cost efficient. Like I said, I thought just getting it to run correctly the way I bought it was the cheapest way, but now I'm not sure.

What do you guys think is best? I do prefer TPI, and I basically need to re-do the entire fuel set-up.

[WildBillyT]

What I would love is to have the car original with nothing cut and TPI on it. I would take you up on that harness in a heartbeat and put TPI back on, but it needs to be cost efficient. Like I said, I thought just getting it to run correctly the way I bought it was the cheapest way, but now I'm not sure.

What do you guys think is best? I do prefer TPI, and I basically need to re-do the entire fuel set-up.

Based on the hack job stuff I'd go with the TPI. 3 fuel pumps, a botched intake install, who knows what timing, etc etc.

If money is super tight and you just want to go down the road you can debug the carb setup.

[88WS-6]

Based on the hack job stuff I'd go with the TPI. 3 fuel pumps, a botched intake install, who knows what timing, etc etc.

If money is super tight and you just want to go down the road you can debug the carb setup.

Money is rather tight. I have the TPI parts sans harness. New stock style in-tank pump is $52. How much would fuel lines be?

[BonzoHansen]

depends if you can find them used.

price gaskets too. do you have all the sensors? correct throttle cable?

[PolarBear]

depends if you can find them used.

price gaskets too. do you have all the sensors? correct throttle cable?

TPI gaskets are kind of expensive IIRC



**EDIT**

NM I was wrong less than ~$20 for the set

FEL-PRO Part # MS930351 $22 with the intake gaskets and TPI

[BonzoHansen]

He'll need intake gaskets too.
t-stat gasket.
air cleaner housing & parts.
might need the correct temp t-stat

he has to fix the fan wiring in either case.

[PolarBear]

You also need to change the distributor, that is a large cap so it is probably isnt going to be a TPI one

[BonzoHansen]

might be. check the module


but if he does he'll need a coil too. and whatever bracket hold it. and a coil wire.

[PolarBear]

He'll need intake gaskets too.
t-stat gasket.
air cleaner housing & parts.
might need the correct temp t-stat

he has to fix the fan wiring in either case.

T-stat gasket is like $0.75 to $3

Fan wiring should be part of the TPI harness

[BonzoHansen]

just adding to the list. "it's easy" turns into a pricy mess that doesn't run right if you plan wrong.


and probably a whole sending unit, not just a pump. give or take the unknown in the tank now.

[88WS-6]

I still have the stock large cap distributor. I could also sell this carb/intake/ignition that I don't need to try and offset some costs. It just sucks because I'll have another car that isn't running.

Insert a lot of expletives...

[Featherburner]

It doesn't get any easier than what you've got right now! A carbureted smallbolck with an HEI. It practically fixes its self. I'm not trying to bust on you but if you can't fix it now what make you think you can add back the TPI and get it running correctly? I'm sure this reads like I'm being a jerk off but that is not my intention. It's a 100% serious question.

[88WS-6]

I agree with you completely. My failure lies in not having any tools and not being able to get under the car. Biggest issue is I don't know exactly what the previous owner did to the fuel system. If the fuel system was untouched, different story. Tune the carb, fix the t-stat, replace the choke or whatever the issue could be would be a lot easier. I plan to get the car towed back to my house since I can't pay anyone else to do this. Expect a lot of pictures and a lot of questions.

[WildBillyT]

I agree with you completely. My failure lies in not having any tools and not being able to get under the car. Biggest issue is I don't know exactly what the previous owner did to the fuel system. If the fuel system was untouched, different story. Tune the carb, fix the t-stat, replace the choke or whatever the issue could be would be a lot easier. I plan to get the car towed back to my house since I can't pay anyone else to do this. Expect a lot of pictures and a lot of questions.

If you are in H'boro I can find time to come by and take a look.

[88WS-6]

Just went to get the car. It started up first try (not sure what they were trying all morning) and went through the entire cold start just fine. Once the car warmed up I tapped the gas to release the choke and it immediately died. Started it right back up and it would die unless I was on the gas, even just a little bit. Is my choke stuck or something? I drove the car to the lot next door and left it for tonight. I'll call for a tow back to my house in the morning

[88WS-6]

If you are in H'boro I can find time to come by and take a look.

Thanks I'd appreciate it. I hope to buy a jack and stands tomorrow. This weekend is the craftsman sale at Sears

[WildBillyT]

Thanks I'd appreciate it. I hope to buy a jack and stands tomorrow. This weekend is the craftsman sale at Sears

If you don't, I have a few spares I can lend you for a little bit.

Oh, and the Lowe's was clearing out the garage kit (big floor jack, 2 jackstands) a little while ago.

[BonzoHansen]

there are always harbor freight coupons in the car mags. if the timing is right for me I'd come over with wbt.

[JL8Jeff]

Sounds like you need to adjust the throttle screw on the carb and try to check the timing to see where it's set. With the choke on(when it's cold) it's holding the throttle open for you. Once it warms up and the choke comes off, it's backing down and sounds like the throttle screw is backed out too far.

[//<86TA>\\]

That idle screw may be loose and vibrated out.

[88WS-6]

Thanks guys. That is something I will definitely check. I don't have a timing light though

[sweetbmxrider]

You don't need a timing light to turn a screw to get the thing to idle.

[BonzoHansen]

You don't need a timing light to turn a screw to get the thing to idle.

Jeff mentioned checking the timing too.

[WildBillyT]

You don't need a timing light to turn a screw to get the thing to idle.

Yeah, maybe a vac gauge.

[sweetbmxrider]

Jeff mentioned checking the timing too.

Overlooked that one.

[88WS-6]

Going to get it towed now. Where is the throttle screw on the carb? I checked the 4160 diagrams and there are like 4 different ones that match that name.

[88WS-6]

Is it the "throttle body screw" on the bottom of the carb just in front of the throttle lever?

[donnj]

the curb idle screw if its there should have a spring around it to keep pressure on it so it cant vibrate loose

[88WS-6]

Flat head sticking up at 45 degree angle towards the windshield?

[donnj]

yes thats the one, the base of the screw should be pressing against the lever that controls the butterflies, as WBT posted get a vac gauge it is needed to get the Holley running perfect. FWIW a timing light is great for getting a base to work off. But to really find the sweet spot and make the motor run perfect you need to listen to the engine.

[88WS-6]

Car is running great now. Thanks guys. I adjusted the throttle screw and its idling around 900 rpms (750 with the fans on).

Don,
I adjusted the two other screws. Driver side was 1.25 turns out and passenger side was almost 3. I set both to 1.5 turns out

[JL8Jeff]

Cool, sometimes it is an easy fix!

[88WS-6]

Cool, sometimes it is an easy fix!

Yea sometimes. It's only temporary as I still need to re-do all of these fuel lines. I'd like to put in a gauge just before the carb as well. I am also concerned about how close my current lines are to my motor and exhaust manifolds (especially the fuel filter by the firewall). I think it may also be affecting me because I have no trouble on cold starts, but after a few hot soaks, I get problems. The location of the lines and resulting heat could be causing air bubbles in the lines or boiling or maybe even vapor lock. The car is still running with no thermostat also...

Do I need to have absolutely no fuel in the car whatsoever to change the fuel lines, or is there a way to cut off my tank and just run out what's in the lines? I'm guessing that since my stock in-tank pump is gone, I'll have to run the car dry. I've been trying to keep the tank to 1/4 at most and it's around 1/8 now (assuming the gauge works).


This picture is the car during cold start Saturday morning before I got it towed:

http://www.fquick.com/images/vehicles/full/41137361371.jpg?1330350656

After I got the car home I adjusted the carb on Sunday and it ran much better. I first adjusted the curb idle screw and I could see the primary plate closing as I tightened the screw (with the car off). Then I adjusted the other two screws to fully tight and then 1.5 turns out. I started the car up and it went through the cold cycle fine. When I took the choke off, it miraculously kept running and didn't die. My idle was too high, around 2200rpms, so I backed out the curb idle screw until I was at 900rpms in neutral. That's still a little low, but I left it there to make sure it wouldn't stall out again. I ran if for 20 minutes like that and I had no problems.

[WayFast84]

Good job man. I can't wait to see this thing.

[WildBillyT]

If you are looking for a reference book, this is a decent one:

http://www.summitracing.com/parts/HPB-HP1052/

Some of the stuff is certainly dated but it's great for things like pump cam selection, idle adjusting, choke settings, etc that don't change over time.

[88WS-6]

Plans to re-do my fuel system:

- Edelbrock 17933 performance in-tank pump (255lph) (http://performanceparts.com/part/Edelbrock/17933)

- All new lines and fittings (suggestions, 6 -AN?)

- Mallory 4309 FPR (for the current carb) (http://www.summitracing.com/parts/MAA-4309/)

- Vacuum gauge

- Fuel pressure gauge

- Fuel filter just before the carb

That should get the car running correctly as-is with my carb. Down the road if I feel like going back to TPI or to HSR or some other EFI, I can just take the FPR out of the equation. Seem legit?

I need to take my tank down one of these days and see what's left inside as far as the pick-up and strainer go. He said he removed the pump but who knows what else could be missing... I'm concerned right now with how it is running because he took out the charcoal canister and the mechanical pump on the block has no return lines. Could this cause vapor lock or excess pressure in the lines/tank?

[BonzoHansen]

Seem legit?
Seems expensive and complicated for a carb on a mild engine. You really need to get under that car, see what you really have, do some testing and go from there. :2cents:

Tank has to be vented somewhere or it will collapse on itself. BBC Camaros ran with no return line, I think yours can too.

I still think your supposed vapor lock is an ignition problem.

[WildBillyT]

Seems expensive and complicated for a carb on a mild engine. You really need to get under that car, see what you really have, do some testing and go from there. :2cents:

Tank has to be vented somewhere or it will collapse on itself. BBC Camaros ran with no return line, I think your scan too.

I still think your supposed vapor lock is an ignition problem.

Back then they had a gas cap that vented to the atmosphere.

[BonzoHansen]

Back then they had a gas cap that vented to the atmosphere.

A 3rd gen? I don't think so. I could be wrong. It had an EVAP system. but I am saying the PO did something to vent it.

[WildBillyT]

A 3rd gen? I don't think so. I could be wrong. It had an EVAP system. but I am saying the PO did something to vent it.

I was commenting on the mentioning of BBC/60's cars running with no return line. The gas cap was vented to allow air to displace the fuel being used. Without a vented gas cap an older car won't run right.

I have not seen his car but if all of the original fuel stuff is ripped out and it's a single line to the tank and there's no venting going on that could be an issue.

Pure speculation though, since I haven't seen it firsthand. I think we are staying the same thing with different words.

[BonzoHansen]

Oh, ok. Probably so.

The pump return line is not related to venting. GM used it on some apps to stave off vapor lock. My point is many cars did not have it and had no issues. I still think there are a number of answers being thrown around that have no question yet.

The OE tank has a vent line, so he likely did something to that line. Or it might also have a one way check vent that allows air in, been a while, I forget. Or he put the wrong (unvented) cap on. If it were totally unvented the tank would collapse, and it would be difficult to fill up.

OP, I hope the tank is low when you try to pull it out. Full tanks are heavy! Also be careful not to bend the filler neck. GM banged that up in 3rd gens, all 1 piece.

[//<86TA>\\]

the 3rd gen tank has no direct vent line, it has a vacuum break line that goes to the back of the rear seat area.

pulling the tank is not too bad, just need a second set of hands and be DAMN SURE you get the car up as high as possible and the axle as low as possible. then there will be no issue with the tank clearing anything or the fuel neck getting caught up. doing this on a lift would be even better.
With no return line, i had vapor lock issues in my car. Usually only when trying to start the car hot, after sitting for a little while. If the lines are insulated where they enter the engine bay, this will probably be a non issue.

I still say remove the electric pump, splice the lines (temporary, should be replaced) and see how the car runs with just the mechanical pump thats already there. Could be a simple fix.

If you run lines, 6an is fine. Factory hard line might be better.

[88WS-6]

Usually only when trying to start the car hot, after sitting for a little while. If the lines are insulated where they enter the engine bay, this will probably be a non issue.

The last time I had issues was after it ran for a bit and then I let it sit for 15 minutes. Car would barely start and then die if I was off the throttle. I'll need to take a trip out in the car and bring it back home, let it sit and then try to start it up after 15 minutes again. I doubt adjusting three screws on the carb fixed that issue.


The only other time I had a problem was when I was driving it home the day I bought it. It would cut out cruising at 65mph on the parkway (which Bonzo thinks is ignition related).

[88WS-6]

*Update*

Phil and I got under the car this past Saturday and removed the Holley blue pump. He can chime in with the details, but it was just getting in the way. We hooked up a fuel pressure gauge after removing it and I'm getting 8-9 psi at the carb (right out of the mech pump on the block) so I'll be getting a regulator to knock that down.



http://www.fquick.com/images/vehicles/full/41137366032.jpg?1341917612

[88WS-6]

Regulator is installed. PO put the banjo fitting to the carb on wrong so we couldn't re-use it. I'm picking up a new one after work today and then hopefully we'll see correct pressure to the carb. After that we are going to bump the timing a little and then Duke Island tomorrow.

Phil you are the man!

[88WS-6]

Well it didn't make it to the meet. The regulator is in and the carb is getting a steady 5 psi, but we couldn't get the motor to run long enough to time it. Seems like it's only running off the accelerator pump because it would only stay running with constant throttle application. Time for a carb rebuild... yay.