PDA

View Full Version : jeep trouble


transamkid
05-29-2007, 03:08 PM
i know some of you guys have jeeps on here, so heres my problem
my friend has a '99 jeep grand cheerokee. we have been taking care of it and all, oil changes and what not then one day it began to make a noise that sounded like a pushrod.
so we pull the valve cover off, and everything is kosher under there, nothing rattling around, so we figured it may be a valve. to fix that we read in his haynes manual to just put high viscosity oil in it *havent done yet* b/c oil was just changed and mobil 10w30 was put in.
so the other day he said he got home and it said add coolant so he puts some in, and it overheats and shuts off, probably due to the overheating, and before it shut off, the pushrod sounding noise was really bad (valve?)
what should we check, replace, what not
its a 4.0L inline 6, 2/4wd

Ian
05-29-2007, 06:40 PM
loosing coolant is never good. take the oil fill cap off the valve cover and look down inside. if it looks like light brown sludge, you've got a cracked head. they usually crack right under the oil fill cap. the 99-01's are the ones that crack the most. if its not that, then it might just be a head gasket.

and you said it overheated and stopped running, thats also not good :lol:

I'd take the spark plugs out and turn the motor over a few times just to make sure everything is still moving freely.

transamkid
05-29-2007, 09:31 PM
yea, well we got it towed from his house to mine, it runs rough, with white smoke and all coming out, so we put it in my driveway, and is now our project. i got to his house, looked at the dipstick, and see the brown sludge and knew it was a head gasket/crack right away. so now we get to tear the top end down, which should be fun. someone told me to replace the timing chain while im at it b/c they start to go also. and ill do that check to see if its a gasket or a cracked head.


thanks

Ian
05-29-2007, 10:03 PM
yeah, you're gonna be taking the head off so you might as well do the timing chain while you've got the car apart.

Pampered-Z
05-30-2007, 09:20 AM
When you get it running again check the relay for the fans. Jeep cheero's seem to have issues with the relays going bad and they will overheat sitting still. They get enough air moving to keep them cool, but stop for a light and they overheat.

The relay is mounted to the pass. side wheelwell. I think the manual states the proper way is to remove the front grill/head light assembly, or pull the wheelwell out. I've done 5-6 in the past few years. We replaced so many in one friend's car ( has over 200K on it ) he keeps a spare with him and we extended the wiring harness and relocated it so we can change in 1 minute.

His has had a lifter/rod tick for the past 75K miles.

Ian
05-30-2007, 06:44 PM
When you get it running again check the relay for the fans. Jeep cheero's seem to have issues with the relays going bad and they will overheat sitting still. They get enough air moving to keep them cool, but stop for a light and they overheat.

The relay is mounted to the pass. side wheelwell. I think the manual states the proper way is to remove the front grill/head light assembly, or pull the wheelwell out. I've done 5-6 in the past few years. We replaced so many in one friend's car ( has over 200K on it ) he keeps a spare with him and we extended the wiring harness and relocated it so we can change in 1 minute.

His has had a lifter/rod tick for the past 75K miles.


I usually take the headlight out and use a hole saw to get to it. its under the plastic thats under the headlight.

transamkid
05-30-2007, 09:20 PM
does that whole relay thing still go for non electric fans also? and ian, i checked under the valve cover, and there was nothing in there, so it might be just a head gasket, but just to be sure, we're going to bring it to a place over here that will check it for cracks for $25.

and the timing chain, whats that whole deal about, i need to take off the water pump and then how do i get the chain off? i have a haynes manual here i will look in it also, but it helps to have the advice from ppl who have done it before, the book makes it sound so easy

Tru2Chevy
05-31-2007, 08:04 AM
does that whole relay thing still go for non electric fans also?

Well, that should have one mechanical fan, and one electric, right? That's the way my '96 is setup, and I'm pretty sure the later ones were the same.

- Justin

transamkid
05-31-2007, 04:18 PM
yea it has both fans i found out, we got all the fluids drained out and all that good stuff, and are now working on the valve cover/intake manifold area. what can we use to disconnect the fuel line, is there a special tool, and if there is, does anyone have it?

jims69camaro
06-08-2007, 04:52 PM
i use a weird looking wrench (not sure of the name) that's slightly closed, but not a box wrench. not open, either, like a regular crescent wrench. sometimes you can get away with a regular crescent wrench, but you have to watch to make sure you don't round it off.

transamkid
06-11-2007, 06:14 PM
yea i got the head off and fuel line (small flat head)
sure enough we have a cracked piston on our hands
=(((

BonzoHansen
06-11-2007, 06:55 PM
i use a weird looking wrench (not sure of the name) that's slightly closed, but not a box wrench. not open, either, like a regular crescent wrench. sometimes you can get away with a regular crescent wrench, but you have to watch to make sure you don't round it off.

A line or flare wrench?

http://www.redhummer.com/myhummer/tools/wrenches/flarenut.jpg

transamkid
06-11-2007, 07:18 PM
no the line need like this scissor looking thing, no wrench, ttp hooked me up and let me borrow the tool, but by the time my dad got it home, i went to town on the fitting with a small flat head and took that sob off, lol
it was like a flared fitting on the fuel rail, and then the line had like tabs around the flare holding it in place

Tru2Chevy
06-12-2007, 10:53 AM
Cracked piston....that sux. Is he gonna rebuild it?

- Justin

transamkid
06-12-2007, 06:55 PM
nah, we're gonna see about putting in a used/rebuilt engine

Tru2Chevy
06-13-2007, 03:38 PM
nah, we're gonna see about putting in a used/rebuilt engine

Well, that's what I was actually getting at. My '96 XJ just got totaled - 103,xxx miles, ran like a champ. I'm going to try to buy it back....if your friend is interested for the motor, have him shoot me an email (tru2chevy at gmail.com)

- Justin