As the tittle says do you have any tips/trick with doing the 3100/3400 lower intake mani gasket,

Doing my sisters 3400 this weekend in her buick Rendevorious(god help me) she call me asking how often a t stat goes out(replaced last year) first question i ask is are you loosing coolant, she pops the hood and looks, we yeah but i don't have a puddle, so lim or head gaskets it is but she said it hasn't driven any different so i am guesing it the lim will do a compression check before i do anything

I pritty much knew how to do it but looked it up on Autozone's repair manual to varify what exactly i need to do, now just looking for any tips/tricks any of you have done/heard of that may make it go smoothly

will be getting the metal ones not the nylon junk

 

Not extreemly excited about this work space...

and i'l be doing it in a single car unheated garage

 

Really fairly simple, I suggest keeping the injectors and fuel rail in the lim to save some time and headaches later. Also keep the pushrods/rockers in order or you could have some serious valve damage. If your resusing the lim bolts clean them up with a wire brush and put some loctite blue on them. Also just replace the tstat while your in there. btw really clean engine bay.

 

Tstat is less than a year old,

i think the pic is a stock photo for a dealership, just stole it off google!

 

Even though its only a year old I personally would just do it because its a bitch to do later. And it's only like $10. Haha I wish my engine bay was factory clean.

 

Getting to the T-stat, I've always removed the Throttle Body (on a N-body car, takes me about 1 hour starting at getting tools ending with putting tools away).

Diagnosing a LIM, get a radiator pressure tester, pump up the system close to the pressure on the cap (it's either 13 or 15 lbs). Inspect where the LIM sits. Odds are, you will see coolant bubbling from the gasket.

As for changing it, I disagree with Rellsun on leaving the injectors in the LIM. Personally, I like to remove the LIM, clean it up as best I can. Any injector O-ring you expose (remove from where it was seated), replace it. Not saying you can't do what Rellsun mentioned, I find it easier to work on cleaning the LIM with it out of the car.

I agree with Rellsun on keeping rockers and push rods in order. The push rods have varied lengths. I also tend to clean up the push rods and rockers (get rid of any oil/sludge from age). A little kerosene and a pop bottle helps with cleaning the push rods.

As for re-using bolts, I have just cleaned them up, no use of LocTite (suppose it wouldn't hurt, but never been an issue).

I'm sure in my work with these I have other ideas, I just can't think of them at the moment. I wish I knew about the aluminum gaskets when I last did LIM gaskets on my '94 Grand Am (back in '09, learned of them about a month after the job).

 

When did GM change the design/material of the LIM gasket? The PO had the LIM gasket replaced in my 02 Monte back in 06 at the GM dealer. So, not sure if they installed the same old crappy gasket, or the improved designed gasket.

 

It's NOT GM that changed the design. Multiple vendors make these gaskets. FelPro makes the aluminum ones. Not sure when they did it, but I learned they were available at least sometime in '09 (maybe longer).

 

So, the current GM gaskets are the same crappy design? I was thinking GM redesigned them. The dealer used GM gaskets in 06. So, I'm guessing they were probably the crappy design?

 

To my knowledge, GM gets them from a supplier and slaps a GM logo on them. As I understand at one point they used FelPro then Mr. Gasket and back to FelPro. At one point, the nylon ones GM sold were "re-enforced" (or re-designed, but still nylon, still crap, I had them on my 3100 Grand Am, no change in life of the gasket).

I believe FelPro is the vendor selling aluminum gaskets. What I don't know is if GM is using those in newer cars or even the "GM" branded replacement parts.

What I can tell you.... Just buy the FelPro aluminum ones for changing your LIM gaskets and not worry about it again. Do NOT use nylon ones at all.