LIM, Head Gasket, Pistons, Replaced [Archive] - Forum


View Full Version : LIM, Head Gasket, Pistons, Replaced

10-03-2005, 06:14 PM
Hey guys. I have three quick questions here:

1.) I went to my mechanic today and I showed him my new found oil leak that appears to be oozing slowly out of the top part of the engine (where its sealed together) and building up on the bottom of the oil pan. He said it was the lower intake manifold, I mentioned that I may need a new LIM gasket, he said he never heard of it called a "LIM" and second off GM doesnt use a gasket and instead seals the engine together with some sort of cement. Is this true??

2.) Since the oil was seeping out of this seal, after its fixed could I expect more power, considering theres a better seal = higher pressure???As of now I cant squeal my tires!! :rage:

3.) He said hed put on a new head gasket and send the pistons to a machinist to see if theyre warped. So is there anything else I could do to improve performance while the top half of the engine is torn apart like this???



10-03-2005, 06:24 PM
i think your mecanic is wrong

needed to fix lim leak

1 x 89017279 - Intake gasket kit
2 x 10154775 - Valve cover gaskets
4 x 11588915 - Short intake manifold bolts
4 x 11588914 - Long intake manifold bolts
Dexcool Coolant
Black RTV sealant
Pack of razor blades to remove old gasket material
Brake cleaner

10-03-2005, 06:45 PM
i agree. i have took the heads off my 3.4l. the head gaskets suck. thats all you need.

10-03-2005, 06:52 PM
? So is there a gasket thats supposed to go inbetween where this engine is sealed and the oil is leaking from. Isnt this where the LIM gasket is supposed to go making my mechanic wrong??

10-03-2005, 06:59 PM
yup search for lim and you willl find a bizillain threads on it, fixing it and peoples stories....about 99 percent of the grand ams with the 3400 will have to get it replaced

10-03-2005, 07:12 PM
BTW, lose the mechanic, he doesn't have a clue what he's talking about. Seriously, cementing an engine together w/ no gaskets? BS. Checking the pistons to see if they are warped? Crazy talk!

10-03-2005, 07:17 PM
He actually showed me the stuff they used to seal the Upper and Lower part of the engine together. He told me he'd send the pistons in to see if they're warped because the engine heat could warp the aluminum which might have been what damaged the gaskets in the first place.

I think the stuff he was talking about is the rtv sealant around the outside of the engine itself.

How exactly do I insert an image, it asks for text when I click the icon?

10-03-2005, 07:24 PM
Gasket sealer wouldn't be a bad idea at all when putting the LIM together, but you sure as heck need a gasket. Removing the pistons is going to require removing the engine. And if you got the engine hot enough to distort the pistons, the heads would be hella warped, you'd have head gasket leaks, all kinds of problems. Sounds like he's after your money more than he's worried about you're well being and financial situation. Go to manage attachments to add an attachment. (picture)

10-03-2005, 07:25 PM
Wait a sec, you said it's leaking oil correct? From your description it sounds like the valley seal is leaking which should just have RTV, there is no "china wall" valley seal on the LIM for oil. The LIM gasket that everyone here replaces is primarily for your intake passages and coolant passages. The gaskets go between your intake and heads, the intake to block just gets RTV - which is most likely to be an oil leak if not properly RTV'd.

If it is the valley seal then no, it won't increase oil pressure or give you more power.

If you have a blown head gasket then you will be down on power but there is no oil flowing through it so it will not leak oil outside the engine. - This is where I'm lost as to why you think head gaskets are bad? Warped pistons?

10-03-2005, 07:31 PM
Your "mechanic" has obviously never done this job before if he doesn't know there is a gasket in between the intake and the heads. I've also never heard of sending pistons out to be checked for warped. If the cylinder heads come off then absolutely they should be send out, pressure checked and planed if needed.

Run, don't walk away from this mechanic.

10-03-2005, 07:36 PM
Where did his mechanic say there was no intake gasket? He's talking about an oil leak from the base of the intake where, just as his mechanic says, there is no gasket. Also where did anybody ever say anything about an intake gasket leaking? All I saw was Sonic say his gasket may be leaking - what coolant? where?

There's just not enough solid info here for a solid diagnosis yet imo. Too much speculation goins on.

10-03-2005, 07:38 PM
? So is there a gasket thats supposed to go inbetween where this engine is sealed and the oil is leaking from. Isnt this where the LIM gasket is supposed to go making my mechanic wrong??
No, there is no gasket between the engine block and the intake, just RTV. This is where oil will leak.

10-03-2005, 07:38 PM
Thanks Coop and everyone else for some fast responses. Im not all that keen on car engines, Im an Info Systems major. I believe my mechanic told me the pistons may be warped due to heat which is causing problems with the headgasket. Now I thought the headgasket came into really close proximity to the piston which is why is could be damaging it; im just trying to make logic why he would send the pistons in to see if theyre warped. Technically Im not having problems with the headgasket or the LIM gasket though, right? Im just having a problem with the rtv sealant holding the intake to the block? Perhaps hes trying to rip me off....THANK GOD FOR GRANDAMGT.COM.



10-03-2005, 07:43 PM
Im sure he knows theres a gasket between the intake and heads. The leak is between the sealant of the block...

The leak is between the two red dots on the sealant on the bottom of the picture...

10-03-2005, 07:44 PM
Not sure about your headgasket piston thing, still kind of fuzzy why you/he thinks it's bad.

Yes, it sounds like you're having problems with the RTV, unfortunately you can't just replace the RTV without replacing the LIM gaskets as well.

10-03-2005, 07:45 PM
Yeah I wonder why he thinks its bad too...
And maybe it was the cylinder heads he was talking about sending in to be checked for warping...

10-04-2005, 12:05 PM
So anyways....$1000 bucks to get new lower intake gasket, upper intake gasket and new head gaskets, to have my pistons checked for warping, new oil, coolant flush and replaced with the green stuff instead of dex cool....Now once I get this fixed all Ill have to worry about is the transmission slip thats also a common prob with gagt's when shifting from reverse to drive...

Maybe once I have this LIM fixed Ill sell this thing....

Maybe the tranny slip had to do with the LIM somehow...



10-04-2005, 12:18 PM
Shop Around!!

10-04-2005, 12:19 PM
Is he having the cylinder heads checked or the pistons? Pistons is outrageous, and I'm sure thats not in the $1000 pricetag. So its probably cylinder heads. Which, unless you severely overheated the car, isn't needed. Head gaskets, not needed, unless you have a leak.

10-04-2005, 12:51 PM
Im sure he said pistons....
Another shop said if I had the intake gaskets replaced to go through with the head gaskets also....

10-05-2005, 04:52 PM
Do hemispherical pistons cost more than normal pistons??? And is it possible to get them put into my v6 when I have the LIM and head gaskets replaced. And also, will it make a difference?

10-05-2005, 05:27 PM
Also, what could I do to add a little more power while my engine is torn apart like this without spending major cash??? Does anyone have any suggestions??
:feedback: :thumbs:

10-05-2005, 06:09 PM
Search man, its all been covered. Basic performance increasing mods are exhaust, headers, DHP PCM, intake, Port and Polish the heads, manifolds, cam, etc.