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View Full Version : 4.7 Head Gasket - 04' Laredo



Lumpy
08-11-2016, 09:47 AM
Yes, I know I've gone missing for a while but...

It all started just over a year ago when the wife was on her way to work and the idler pulley froze and trashed the belt, she kept driving the lat 5 miles and it overheated...boiled over (yes I know it starts out bad!) So fixed the pulley, new belt and added coolant. Drove for a few months adding coolant every so often, no smoke and oil looked good. Then it started to overheat again, found out the fan was not spinning properly, replaced power steering pump and we were good for a while but still using coolant. Finally found the leak - replaced water pump and it was fine for 6 months or so...then it started to get warm again and she was able to get to work before it got too hot. Coolant was fine, added 2 cups and drove it home, 20 miles mixed driving. Replace thermostat and it overheated straight off. So then the last thing to change is the rad and you bet this time I see the infamous white smoke...The head gasket finally popped after a year or so after the first overheat.

I have Googled and Googled and this is when I decided to join...I need some advice/assistance/shoulder to cry on. My mechanic buddy stated these engines do not like to be opened up but I have to give it a go, need to keep the old girl alive for as long as possible. Were still in good shape with about 150K on the clock.

I have ordered a gasket kit with lifters and bolts and I believe I have most of the tools I need to pull the heads. I have changed a few 90's Toyota HG's without any issues so I figured what the hell.

My main concern is the timing chains, I really don't want to pull the front of the motor apart. I have read that you can make a wooden wedge to keep the chains from falling...does this actually work? I'm going to check the heads but for going a year+ after the overheat I'm hoping I don't have to have them shaved.

Any input would be greatly appreciated, I'm starting the tear down this weekend and hope to have it running by next.

DMG
08-11-2016, 06:06 PM
In cam chain motors like that I have used bungy cords between the hood and the loose chain to keep it from slipping off the crank gear. No guarantees it will hold it but it has worked for me.

Lumpy
08-11-2016, 06:44 PM
Thanks DMG, that's how I did the head on my Toyota...Forgot about that! What I have read the tension can be a real bitch...

tow hook
09-07-2016, 01:34 PM
Yes, I know I've gone missing for a while but...

It all started just over a year ago when the wife was on her way to work and the idler pulley froze and trashed the belt, she kept driving the lat 5 miles and it overheated...boiled over (yes I know it starts out bad!) So fixed the pulley, new belt and added coolant. Drove for a few months adding coolant every so often, no smoke and oil looked good. Then it started to overheat again, found out the fan was not spinning properly, replaced power steering pump and we were good for a while but still using coolant. Finally found the leak - replaced water pump and it was fine for 6 months or so...then it started to get warm again and she was able to get to work before it got too hot. Coolant was fine, added 2 cups and drove it home, 20 miles mixed driving. Replace thermostat and it overheated straight off. So then the last thing to change is the rad and you bet this time I see the infamous white smoke...The head gasket finally popped after a year or so after the first overheat.

I have Googled and Googled and this is when I decided to join...I need some advice/assistance/shoulder to cry on. My mechanic buddy stated these engines do not like to be opened up but I have to give it a go, need to keep the old girl alive for as long as possible. Were still in good shape with about 150K on the clock.

I have ordered a gasket kit with lifters and bolts and I believe I have most of the tools I need to pull the heads. I have changed a few 90's Toyota HG's without any issues so I figured what the hell.

My main concern is the timing chains, I really don't want to pull the front of the motor apart. I have read that you can make a wooden wedge to keep the chains from falling...does this actually work? I'm going to check the heads but for going a year+ after the overheat I'm hoping I don't have to have them shaved.

Any input would be greatly appreciated, I'm starting the tear down this weekend and hope to have it running by next.



the head bolts get turned 90 degrees past the torque spec, so you will need new bolts, and replace the chains, all 3 or you'll do it twice like I did. and yes the tool helps, aka the block of wood. I still have mine as a reminder.. lol also the manifold bolts brake, and the manifolds are know the crack. used manifolds are pretty cheap. for the broken studs, weld a nut on the end, the heat helps them come out. and the nut is place spin it off the head.

Lumpy
09-13-2016, 07:03 PM
It's all buttoned up, got done a few weeks ago...2 weekends, roughly 3 days and it was running. Didn't pull the front apart, the chains and tensioner's looked good. New headbolts and I did purchase the tool to turn the 90 on the bolts.

tow hook
09-15-2016, 01:06 PM
It's all buttoned up, got done a few weeks ago...2 weekends, roughly 3 days and it was running. Didn't pull the front apart, the chains and tensioner's looked good. New headbolts and I did purchase the tool to turn the 90 on the bolts.

glad to hear that it worked out :)