Write-Up: Lower Intake Manifold (LIM) Gaskets

the clubgp link is in the 1st post, but it's hard to see because of the colour of hyperlinks...

Some info I found about the LIMs and Dexcool: http://www.3800parts.com/

AA wrote:

Some info I found about the LIMs and Dexcool: http://www.3800parts.com/

I think I've referenced his Dex-Cool article before - http://www.zillamotorsports.com/DEX/

Thank you guys. That http://www.3800parts.com/ link has some good information regarding our intake manifold/gaskets, cooling system, etc.
I think I will be doing this aluminum gasket change next. I might as well go just a little further down when I do the rocker arm kit swap.

Cheers

You can do the rocker arms without removing the blower or LIM.

AA wrote:

You can do the rocker arms without removing the blower or LIM.

Yes, I realize that. But I'll already be under the hood.

Just did my LIM gaskets. While I was in there, I put on a Thrasher 3.5" pulley, new radiator, 180 thermostat, new Delphi radiator, new radiator hoses, new GM water pump, and replaced the injector O-rings.

Just about ready to fire it up. Have not put the plastic splash guard under the front of the car yet, so I still have all of its plastic push clips out as well. However, there is a few other things I can't seem to figure out where they came from...

- Two long (3" or so) small headed (10mm? Don't have them at hand...) lag-screw style bolts. Black in color.
- Two clips. Silver/chrome. Flat, thin metal, but folded into a quasi-C-like form.
- Smaller bolt. Small (10mm?) head. Silver finish. Roughly 1-1.25" long.
- Nut exactly like those that hold down the fuel rail. (Yes, my fuel rail is fully bolted down...)
- Nut exactly like those that hold the coil bracket to its studs. (I put the ground lug from the harness under the upper coil bracket bolt going into the head. Saw no other location this was needed.)

Note that my fans are not attached in the center or top in any way. (Other than if the top plate holds them...) They don't really seem to be moving, but that has me a little concerned. They are in the bracket in the bottom, and I have the bolts in the outer sides. But I don't recall if there was anything at the top, but just want to be sure.)

Help!

If you post Pic's of what is left over we might be able to identify things a little easier.

I recently did a similar job, had engine pulled and radiator out, so I'll give this a shot, see what I could come up with inline:

keller wrote:

- Two long (3" or so) small headed (10mm? Don't have them at hand...) lag-screw style bolts. Black in color.

sounds like fan mounting bolts

- Two clips. Silver/chrome. Flat, thin metal, but folded into a quasi-C-like form.
- Smaller bolt. Small (10mm?) head. Silver finish. Roughly 1-1.25" long.

sounds like the above two are condensor-to-radiator upper bolts

- Nut exactly like those that hold down the fuel rail. (Yes, my fuel rail is fully bolted down...)

also used on the EGR heat shield, only place I can think of

- Nut exactly like those that hold the coil bracket to its studs. (I put the ground lug from the harness under the upper coil bracket bolt going into the head. Saw no other location this was needed.)

the ground wire is held under the second nut - the first nut holds the tensioner on, the second nut just clamps the coil wire in place.

deekster_caddy wrote:

- Two long (3" or so) small headed (10mm? Don't have them at hand...) lag-screw style bolts. Black in color.

sounds like fan mounting bolts

Feared that. Where might they go. exactly?

deekster_caddy wrote:

- Two clips. Silver/chrome. Flat, thin metal, but folded into a quasi-C-like form.
- Smaller bolt. Small (10mm?) head. Silver finish. Roughly 1-1.25" long.

sounds like the above two are condensor-to-radiator upper bolts

Hmm...Not sure the clips have holes for the bolt. Will check. And post pics if I can. The condensor is affixed to the front clip with bolts and the small L-brackets already, so that isn't what I'm talking about. The clips are an odd shape.

deekster_caddy wrote:

- Nut exactly like those that hold down the fuel rail. (Yes, my fuel rail is fully bolted down...)

also used on the EGR heat shield, only place I can think of

OK. Not sure it will move regardless. Have to see if it will mate with anything there.

deekster_caddy wrote:

- Nut exactly like those that hold the coil bracket to its studs. (I put the ground lug from the harness under the upper coil bracket bolt going into the head. Saw no other location this was needed.)

the ground wire is held under the second nut - the first nut holds the tensioner on, the second nut just clamps the coil wire in place.

Figured as much. Moved the ground location to the head, so that nut may be irrelevant.

keller wrote:

deekster_caddy wrote:

- Nut exactly like those that hold the coil bracket to its studs. (I put the ground lug from the harness under the upper coil bracket bolt going into the head. Saw no other location this was needed.)

the ground wire is held under the second nut - the first nut holds the tensioner on, the second nut just clamps the coil wire in place.

Figured as much. Moved the ground location to the head, so that nut may be irrelevant.

ahhh... it will be until you start having odd misfire issues and replace the CPS and ignition module... then figure out it was a grounding issue. it was done that way for a reason, and I recommend doing it that way to ensure a proper ground for that ignition module. It can be very finicky and take three minutes to correct.

The studs that the coil/module setup mount to are going into what? Thought it was the head... I guess if I can swing the eyelet down there, it is no big deal.

Already have the sides of the fans mounted, and shorter bolts went into the radiator tanks to mount them. Are these longer ones for the top inner corners, perhaps? Don't believe they went through holes in the top of the radiator aluminum, as the old foam hasn't any holes pierced in it that I recall. Will look.

Sorry I don't recall. I remember some long lag bolts like you describe, but all I can remember is condensor/radiator/fan, not exactly where.

As to the studs/coil mounting setup, can you take some pics of what you've done? I will try to grab some pics of mine tonight to compare. Also take pics of the pile of bolts you have left (organized please, not in a pile!)

I think I have it all together. Only one stray bolt is left, and it may not even be from this car. Or that is what I will keep repeating as I drive...

The long bolts mounts the fans at their upper inner corners through the top of the radiator...through the clip on piece that I neglected to move over from the old radiator. I moved the bottom one over, but not the top one. Sooo...off came the top cover, and I moved the clip on brace, screwed in the bolts, set the fresh foam down (A/C wall unit surround foam - $2 at the hardware store), and screwed the cover back down.

The small nut went on a stud in the EGR area. Don't think its absence would have meant much, but reinstalling it was trivial.

The nut was indeed to hold the ground on one of the studs below the module. However, the studs go into the head. The bolt along the top of the bracket also goes in the head. Doubt one or the other location really makes any difference. But, I moved it.

The clips were the ones that assure the compression fitting fuel lines don't come apart atop the supercharger. Critical? *shrug* They are clipped back in.

I have a few pics of things as I did them I will post shortly.

BTW, I got a new Delphi radiator delivered to my door for $130. I think that is pretty hard to beat. Look for "thepartsladi" on eBay. Better deal than RockAuto or any other source I found.

Glad to hear you got all the parts back in the right place. Take a picture of the one leftover bolt, I bet we can identify it!

Good deal on the radiator too. I had a new tank put on mine and the rest of it cleaned out for $80, but $130 for a complete new one is hard to beat.

Jason wrote:

IBx1 wrote:

My '95 didn't even have a gasket on the air intake...I'm glad K&N's filter came with one.

Wait, are you talking about an oil filter? Never mind then.

The lower intake manifold gasket is not on the air intake or the oil filter.

It's on the lower intake manifold

Cool! This is the first time I've ever seen the balance shaft.

Eldo wrote:

Jason wrote:

IBx1 wrote:

My '95 didn't even have a gasket on the air intake...I'm glad K&N's filter came with one.

Wait, are you talking about an oil filter? Never mind then.

The lower intake manifold gasket is not on the air intake or the oil filter.

It's on the lower intake manifold

Cool! This is the first time I've ever seen the balance shaft.

I like my balance shaft diabled

AA wrote:

no reason to replace the LIM unless you port & polish it. Might as well do the same to the blower since you'll have it off. I plan to do the gasket sometime this year. You'll know if the gasket is leaking if your plugs have deposits. Oil analysis will confirm coolant in the oil.

I plan to replace my LIM gasket in auto class next week. While having everything taken apart, I want to do any cost-effective work that can be done while I'm in there. Would port/polishing my LIM make much difference in any performance aspect? What about port/polishing the blower? Is there anything else you guys recommend doing while I have everything taken apart?

Isn't your time limited as to what you can accomplish in class.?
Don't you have to start and finish the job while in that session or can it be left apart, for period of time, while you do all the polishing, etc.?

The reason I ask is that you'll be pressed for time just doing the LIM gasket swap, if your taking a night course.

Rickw wrote:

Isn't your time limited as to what you can accomplish in class.?
Don't you have to start and finish the job while in that session or can it be left apart, for period of time, while you do all the polishing, etc.?

The reason I ask is that you'll be pressed for time just doing the LIM gasket swap, if your taking a night course.

I can leave my car in the shop and continue the next morning, time isnt much of an issue.

Well, that's good. Then I guess you could start gathering the necessary abrasive rolls and flap wheels needed to do the job of porting a little and polishing. It certainly can't hurt as long as you don't over do it.

i ported my manifold, also paying close attention to the water passages,and the exhaust manifolds. i did notice the engine breathing a little better on the top end. but its more a "seat of the pants" thing.

I've become a little confused, maybe someone can set the record straight.
Does the after market, like Fel-Pro provide the revised Aluminum LIM gaskets or are these still a dealer only part.?

I thought I read somewhere that Fel-Pro was making the revised version now.

I would like to buy the gaskets I need to do the job soon. I have someone I trust willing to do the labor for me, all I need is all the gaskets.

Rick, I have also been told that Fel-Pro now supplies aluminum gaskets for this. Best bet - order the felpro if they are really that significant a savings over what you can get the gaskets from Monster for. If they come in and are plastic, return them and order from Monster...

Any input in what else I need, my head is in the fog at the moment.

If I tap and plug the 2 coolant holes in the LIM that go to the TB, I won't need the O-Rings, is that correct.???

I planned on pulling the TB to do a thorough cleaning. So I will need a gasket if i do that while he's working under the hood.
That's a bench top job I can do, along with cleaning gasket surfaces.
Any bending over the hood will be left up to the tech doing the job for me.