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PolarBear
08-23-2013, 10:58 AM
Should I expect more than 20-25psi during cranking? This is my 4.8 LR4. I only get about 20 psi during crank and I'm not getting oil through the push rods yet. I crank for about 10 seconds at a time
PolarBear
08-23-2013, 12:08 PM
Ok, I feel a little better now. I went to lunch for a while and started cranking again. I got a little oil out of a few of the push rods, and after a few more cranking attempts I got it out of all the right hand side rockers. I'll pull the other valve cover and make sure they are ok too
WildBillyT
08-23-2013, 12:27 PM
I'm no expert but 20psi during cranking seems OK to me. It's not like the starter is going to have the power to spin the oil pump fast enough to build a lot of pressure. If you have the plugs out too then it's probably spinning more than fast enough.
Blackbirdws6
08-23-2013, 12:30 PM
20 psi is fine for priming. As long as you are getting oil to the top end, you are good to go.
PolarBear
08-23-2013, 12:38 PM
Oil out of all the push rods except the number 1 intake. Pulling the valley cover now


Ok, thanks for the word. I was going I didn't pinch the oil pickup o ring installing the pickup
PolarBear
08-23-2013, 12:57 PM
Ok the roller on the lifter looks wet with new clean oil, but nothing out off the pushrod still. Really really don't want to pull a head, should I just try starting it when I am to that point and see what happens?
PolarBear
08-23-2013, 01:00 PM
Forgot to say, I pulled the rocker and blew out the pushrod. Just did it again and the end in the lifter had a lot more oil on it this time. Nothing trapped in there though
Blackbirdws6
08-23-2013, 01:17 PM
How much cranking have you done total?
WildBillyT
08-23-2013, 01:18 PM
How much cranking have you done total?

Sounds like enough to shoot oil out the pushrod :nick:
LTb1ow
08-23-2013, 01:21 PM
Isn't this a junk motor...?

Just crank it, run it, and drive.
Blackbirdws6
08-23-2013, 01:22 PM
Sounds like enough to shoot oil out the pushrod :nick:

Thanks Bill. :bertstare: I was only asking because perhaps it wasn't enough to get oil up ALL of the pushrods.
PolarBear
08-23-2013, 01:22 PM
How much cranking have you done total?

Sounds like enough to shoot oil out the pushrod :nick:

Yeah, quite a bit. It flows out of the rest of them nicely while I crank so I don't get it. The lifter is putting out oil, I pulled the rocker and cranked it for a second without the push rod and oil flowed over the top of the lifter.
WildBillyT
08-23-2013, 01:38 PM
Thanks Bill. :bertstare: I was only asking because perhaps it wasn't enough to get oil up ALL of the pushrods.

Obscure 'jackin it joke is obscure.


I know what you meant, and it could be the case.

Bear, have a look at this link:

http://www.chevelles.com/forums/showthread.php?t=353278

Maybe try swapping the pushrod?
PolarBear
08-23-2013, 02:57 PM
Tried swapping the intake and exhaust, but the battery is almost dead :p going to the movies in a bit, give the battery some time to recover. It's been in the trickle charger the whole time. In the mean time I'll keep putting the rest of the engine together, I should be able to wire everything tomorrow and try hooking up the HP tuners and firing this thing.