Gm 3.4l -- I Hate You!!

[gdawgs]

I am working on a 99' Pontiac Transport minivan for a friend of ours. It is some charity work because I felt really bad for this gal. She has 6 kids, her husband left her a few months back, and she had no way to pay for the repair. And if she didn't get it fixed it would eventually destroy the engine.

A few weeks ago she came over and mentioned that her temp gage was getting really high. So I checked the radiator level, and it was low so I added water/antifreeze. Then it's fine for a few days, then low again. So I do some research on the internet and find that it is common for the lower intake manifold gasket to fail on this engine(and quite a few of GM's). So I offered to fix it for her.

It ended up being a much bigger job than I anticipated. This is a $1,000 repair at a shop, now I know why. I spent about 8 hours on Saturday tearing it apart. Then about another 6 hours cleaning and reassembling on Sunday, and still did not finish it. I spent several more hours on it yesterday finishing it up. I go to start it up, and I have gas shooting out of the fuel rail return line. I almost cried. :crybaby: I'm guessing the O-ring didn't seat properly.

It will take me several more hours to tear it down to that point again and make the repair. I am so frustrated.


Here are some photos of the muck that was in the engine. Warning, these are very graphic :p

Here are the valve covers, check out all the sludge.




Here is the lower intake plenum. More sludge.



Here's the back half of the engine with the lower intake plenum removed, showing the failed gasket.



Here is a closeup of the culprit, where the gasket failed(upper-right corner of the cooling port).



I spent a good 3 hours cleaning everything up before assembly.

[neanderpaul]

I feel you man. Sorry for the stress. You are doing a good thing. I can't imagine leaving 6 kids?!! I go crazy if I have to work late and can't put my 2 girls to bed. I'm sure she is grateful for you.

[xanthinic12]

wow that should be in a castrol commercial

[BigWheel]

Gdawgs, for what it's worth I think you're doing a really good thing. I've worked with folks in similar situations and it is a huge deal to have someone willing to step up and help. I know it's a pain but hang in there.

[IdealSociety]

ive had to do the same thing for my fiance's grand am with the 3400 engine.

had the dealer do it the first time, then when they used the wrong rtv and it happened again, i did it myself the 2nd time!

im not sure why its such a common problem.

[neanderpaul]

ive had to do the same thing for my fiance's grand am with the 3400 engine.

had the dealer do it the first time, then when they used the wrong rtv and it happened again, i did it myself the 2nd time!

im not sure why its such a common problem.

I'd have charged them for it!

[IdealSociety]

wasnt worth the downtime imo.

id rather do it myself over a long weekend and know it was done right the first time, than wait a week for someone whose messed it up before to possibly do it right their 2nd go around.

[Gforcefd]

Yeah the 3800 GM engine has a similiar issue. It is great your doing that for her though. I had to change the brakes on a friends car when she was in a tough spot. Not as difficult, but your always taking a risk working on a friends car your not used to.

Logan

[littlecar]

All GM V-6 have some kind of gasket problems. Fact of life. Just make sure you replace the old gaskets with the up-graded ones.

[hotfordcat]

All you have done for her and her family will be returned to you ten-fold.

[fishnjeeps]

The 3.8 has an issue with the upper intake melting (not the gasket) It's a bit cheaper ($600) but still a pain. Just replacing spark plugs on my Grand Prix takes 2 people and a very large crowbar. GM needs to work on their engine designs and make them easier to work on. Hope everything works out on it. And good luck!

[bhazard]

So youre doing all this work for her, and shes single?

Giggity giggity giggity.

[jr.fester]

I did my dads on his grandam over the summer and complained. couldn't imagine a minivan and the cramped space. bonus is it comes apart the second and third time alot quicker. I cracked the upper and lower manifolds from over tightening.

[stevewl1164]

I work at a Chevy dealer and have been told it is the 100K antifreeze that eats the gaskets...Dexron's fault! It affects all gm cars. The worst engine GM built was the 3400 double overhead cam used in the Lumina Z34...no warranty company will touch it!

[festivaWES]

A guy at my work has a montana with that engine platform....we did the lower/upper intake manifold gaskets as well......junk motor.