LIM Gasket Replacement

**KZOO3800** · 05-19-2011

1997 Pontiac Grand Prix SE 3.8 Series II NA 165,000 miles original everything.

On Saturday my mechanic is going to install a new fuel line along with a new fuel filter since the ones I have are rusted together... then he'll let me know finally what is going on with my engine. Within the next two weeks if he says everything looks ok I'm going to have him replace LIM gasket, valve cover gaskets, lifters, and intake plenum.

Can anyone quickly remind me which LIM gasket set to get? I know metal ones are recommended, but do I need a certain set? Oreily has them for like $43 with locating pins. The valve cover gasket set is about $13, intake plenum about $130, and lifters $13 a piece. Is there anything else I'll need to buy besides the coolant elbows? I've got until next weekend possibly two weeks until he does the job.
Thanks I just want to do it right while he has access to this stuff.

**FordMan77** · 05-19-2011

Get the Fel-Pros for the LIM gaskets, or get them from the dealer. Also, since you are doing VC gaskets don't forget to replace the grommets as well since this is usually the cause of the leaks. You will also need new injector o-rings (both upper and lower orings) as the ones you have are due to be replaced and may leak if reinstalled w/o changing.

You might as well replace the thermostat and the PCV valve too. Clean the TB out, clean the MAF, make sure you get a TB gasket (they sometimes come in the set w/ the new UIM). Do a cooling system flush and refill with your flavor of coolant, either Dexcool or regular green coolant. Just don't mix the 2.

Why are you replacing lifters? Do they tick? Causing a miss/CEL?

Also, if you have basic hand tools a torque wrench and can follow written directions all of the things you are going to have that mechanic replace can be done by yourself in a weekend at best. The shop is probably going to get about $800 for all that extra work. I'd let him replace the fuel lines and then do the rest yourself.

**BillBoost37** · 05-20-2011

Rockauto has the UIM for ~$85, wanna split the savings?

FelPro
MS98014T Aluminum Lower Intake
VS50080R.........Valve Covers (L36) w/o grommets
ES72833...........Valve Cover grommets
Dorman
47065..............Coolant elbows
UIM aka Plenum. Comes with all kinds of stuff. Inj o-rings, pcv, tb gasket, etc etc.

**KZOO3800** · 06-02-2011

Hey thanks both of you. It took a while but I saved the money for the job. Took me a month building Oil Filters for 12 Cylinder engines to afford this and the expected labor.

I priced out the cost of parts to replace the following including several auto parts stores:
-LIM gaskets (aluminum) $75
-Plenum (Dorman) $129 **Does this come with TB Gasket?
-Valve cover gaskets $12.99
-Grommets for VC gaskets $12.99
-Coolant Elbows $4.99 (I hear Oreily's may have problems based on orings...)
-Throttle Body Gasket $4.99
-Fuel Injector Orings ??? Still can't find exactly what to use...

The dilemma now is that my mechanic and his shop wants to charge me about 150% for all parts even though they'd be getting the parts from exactly the same parts store I could buy them from. The quote for the LIM gaskets was $131.98 for the parts and $335.45 for labor with $3.96 for shop supplies. Holy $hit. I'd rather break something learning how to do this than pay $335 for straight labor. I could re-buy most of my stolen tools for $335.

Anybody know of a more complete Walkthrough for such a job on the web so I can just do it myself? I've already got the video link posted here for LIM gaskets and lifters.

**FordMan77** · 06-03-2011

For a new UIM (plenum) and all the gaskets (for the upper half), injector o-rings, new vacuum connector for back of plenum I recommend the one below.

GM Intake Manifold Kit - iNeedParts.com

I installed this on my 00 GT when I dropped the new motor in and it has yet to have an issue. It also resolves the issue of the EGR heat causing the interior of the UIM to crack as it includes the smaller diameter pipe that you install in your LIM. Also, if you look on that link towards the bottom there is a How-To there as well

**BillBoost37** · 06-03-2011

Now price all that stuff on Rockauto. You'll find the plenum (last I priced) was ~80.

Pretty big savings. Then use a discount code and you save like 5% more.

**Scottydoggs** · 06-03-2011

mechanic shops always tack on a extra 20 % on the parts, thats how they make a living.

**KZOO3800** · 06-03-2011

Rock Auto priced to ship @ $308, including a ps pump, ps hose, ps in line filter and lower ball joint I also needed. The Cardone intake on their site has the steel EGR passage so I may go with that.

**matt5112** · 06-03-2011

Working as a parts guy for a shop....

I can honestly say markup is typically 25-50% of cost.

**KZOO3800** · 06-04-2011

I bought a tool set to replace all the tools that got stolen from me, and I also got a 2 ton hydraulic floor jack, jack stands, ramps, a gasket scraper, and tire wedges.

My biggest concern is what to inspect/service/clean while I have the LIM off the engine. Second biggest concern is what may crack/break/tear/etc. simply because I'm pulling apart vacuum hoses and wiring components on my 14 year old engine. I build and inspect Detroit Diesel/MTU engine components all day in my family's machine shop but that doesn't help me understand how to tear apart the top half of a SII 3800.

I want to take detailed pictures and possibly create the "3800 NA LIM/UIM/VCG Guide For Noobs" if I can do this correctly. Otherwise I will create the "Destroying The 3800 NA For Noobs". Win Win for you guys. Who knows the difference could be a few pointers from you guys who know what you're doing.

**FordMan77** · 06-04-2011

Once you get everything torn down just make sure all the surfaces on the LIM are clean (top and bottom). Then clean the heads off just as good. Also make sure that the top edge of the block is clean where the gaskets set on there (don't forget some RTV at the corners where the heads/block/LIM meet). Buy a few cans of brake cleaner and make sure everything is spotless. You will also want to clean the throttle body. Other than that its just like tearing any other pushrod top end down. May want to mark the fuel injector connections to be sure you put them back on the correct spot. Usually the wire harness will lay where it belongs and you can't mess it up, but there's always the chance.

The biggest issue I had after doing this was fuel leaks at the injectors. Once you fire it up for the first time check all the injectors really closely to be sure they aren't leaking any fuel. I had one that didn't seat right and worked itself loose after a drive and was pooling fuel up on the LIM.

Also be carefull with the metal flex tube that connects the EGR valve as it likes to crack in between the accordian parts and cause a leak.

And when you remove the LIM be sure to plug ALL the ports to the engine as you don't want to drop anything down into the heads. Trust me, its not pretty (lunched my motor this way).

**matt5112** · 06-04-2011

To be quite honest... you dont need much to do a LIM jobber.

Vice grips.

10 MM deep socket.

6" extension.

3/8ths ratchet.

brake clean.

rags.

**brandonl2000** · 06-04-2011

Originally Posted by matt5112

To be quite honest... you dont need much to do a LIM jobber.

Vice grips.

10 MM deep socket.

6" extension.

3/8ths ratchet.

brake clean.

rags.

and a 13mm and a 15mm socket for the accessories.

**matt5112** · 06-04-2011

Hmm.... yes.... yes indeed....

Maybe a 13 mm wrench to aid in removing the positive on the alt.

and a 5/16's for the batt cable.

Overall, small inexpensive socket sets will have you covered.

**KZOO3800** · 06-08-2011

I got my parts ordered. Got the UIM recommended by FordMan77 and ordered everything else from Rockauto.com. I've got a friend of mine who is a master mechanic who is going to do the job with me. He's done this on a Supercharged 3800 in a Regal. Now I'm just waiting to get my parts

Here's the new UIM:
GM Intake Manifold Kit - iNeedParts.com

Here's the rockauto parts:

**FordMan77** · 06-08-2011

So you bought an extra set of injector o-rings? Guess it couldn't hurt to have a spare set laying around.

**brandonl2000** · 06-08-2011

and valve cover grommets should have come with the gaskets...so you might have extra ones. i bought fel-pro vc gaskets and got grommets with em.

**KZOO3800** · 06-08-2011

FordMan77 is right. Plenum came with the o-rings.
The valve cover gaskets, however didn't come with the grommets so I got those separately. It said "w/o grommets".

I found a thread on this forum about coolant elbow issues.
http://www.grandprixforums.net/coola...ain-42943.html

In your experience is there a method of installation/specific o-ring/specific RTV that puts a stop to these leaks? I think that in the above mentioned thread BillBoost37 probably nailed it with the install method, but I want to bulletproof these damn things.

Also I got my brother's digital camera to take pics of the whole job (in fact I guarantee that if I donate a 6-pack of Labatt he'll take amazing photos himself). Bonus!

Anyone, feel free to recommend or request a specific photo(s) you think will help forum-members in the future. We'll make sure to take pics of specific steps and specific parts. All you gotta do is ask and I will toss the list in my tool box before we even get started!

**FordMan77** · 06-09-2011

I didn't see PCV valve on your list. Might as well get that in there new to go along w/ all the nice new parts if it hasn't been changed in a while.

As far as the coolant elbows I put a small dab of GM gray RTV in front of entire o-ring where it meets the LIM and block on the 2nd one. No leaks so far.

My theory is that as you install the elbow the RTV will be forced backwards over the oring in a thin layer thus sealing up any gaps/irregularities in the sealing surfaces of both the elbows and the LIM/block. Not sure how good of a theory that is but it seems to be holding. Just don't go nuts w/ the RTV as you want just enough on there to catch any gaps but not keep the elbow from pushing in all the way.

Don't forget to put some sealer on the LIM bolts as you install them to keep oil from wicking up the threads, and above all else once you get it all back together and fire it up check, then double check, then triple check that you do not have any injector o-rings or fuel line connections leaking. I had 1 injector work its way down just a hair and it was filling up a divot in the LIM. Caught it as I drove to work. Nothing like popping the hood and seeing boiling gas sitting on the outside of your LIM!

Also, once you get the UIM off I would plug all the LIM holes w/ shop rags so nothing gets down in there by mistake. Then once you pull the LIM off do the same with the heads. Trust me, a misplaced bolt will not make your day

**KZOO3800** · 06-15-2011

Parts are in. Looks like my friend and I will be doing this on Friday.

Can anyone clarify the contents of this next pic for me? I know large black one is MAP sensor o-ring, and smaller orange ones may be for coolant elbows...? No idea what that blue ribbed thing is or the smaller black o-ring..
http://i22.photobucket.com/albums/b3...2/IMG_0132.jpg

Also, I know these blue rings are fuel injector o-rings, but what about the black metal ones?
http://i22.photobucket.com/albums/b3...2/IMG_0130.jpg

Thanks again guys.