Upper/Lower intake manifold gaskets

[karrkrazzie]

Getting ready to do my upper and lower intake manifold gaskets tomorrow fr the first time on my 99 lumina 3.8. I got the steel reinforced set from napa. I am just wondering if there is anything special I need to know about the project before I get started, any pointers or special instructions, thanks a lot for anything.

[AL]

Check out the FAQ section... There is a write up in there that should help you

[mfewtrail]

Check out the FAQ section... There is a write up in there that should help you

 

http://www.w-body.com/showthread.php/44936-L36-upper-amp-lower-Intake-Gasket-Replacement-Factory-service-manual-scans

[karrkrazzie]

The car has 162000 miles on it, I was thinking that maybe it would be worth it to replace the head gaskets while im in there, mostly cause it would suk to have to do this all over... My car is not showing any signs of a bad head gasket. I guess I am just wondering if it is worth it if they arent bad yet?

[ron350]

You just don’t hear about 3800II head gaskets going bad.

[Addicted to eaton]

i have a motor with 274k miles on it. ran a smaller pully over 100k of the miles. And it had no head gaskets yet. Infact i have never blown one. and thats saying something.

[xtremerevolution]

Right, my last 3800 went 214k miles before I pulled the head gaskets as I wanted to port the heads, and they were perfectly fine. This is not an issue on these engines.

[karrkrazzie]

then i shall leave them alone, thanks guys.

[slick]

I dunno, I've seen several 3800 with blown head gaskets.

[Addicted to eaton]

weird. i can't remember one. Not question your word or anything thing chris. I just mean weird lol.

[slick]

Ask Rob. He's had to do a couple.

 

I've seen others with failed gaskets as well.

 

 

Not quite as common as the 60*'s though.

[AL]

He cant really ask Rob, as Robs banned

[slick]

Facebook? Email? Phone?

[Andrew]

get new coolant elbows and the improved upper manifold. Forget the headgaskets. Drain some coolant so you dont make a mess. Oil in the LIM is normal. There are 2 blind bolts that will be hidden by the oil. Follow torque specs when puttin it all back together.

[jimmyfloyd]

Agreed. Get a new coolent elbow and make sure you remove the old one completely. Don't do headgaskets. About 3/4 of the time you hear about head gaskets going it is actually a leaking LIM/UIM gasket giving it the symptoms of head gaskets. Make sure you clean the mating surfaces and make sure to use some silicon around the side pieces for the LIM as there is a small space at the edges that might need to get filled. Replace your injector O rings if you have to remove them as a preventative measure. A lot if the engine fires have been attributed to leaking injector o rings.

[BXX]

Ask Rob. He's had to do a couple.

 

I've seen others with failed gaskets as well.

 

 

Not quite as common as the 60*'s though.

 

Only way you will ever blow a headgasket on a 3800 is way way way too much boost, or it was overheated to all fuck too many times, or the coolant system got highly acidic and started eating away the gaskets.

 

With iron head and iron block, its hard to blow them.

[alec_b]

Only way you will ever blow a headgasket on a 3800 is way way way too much boost, or it was overheated to all fuck too many times, or the coolant system got highly acidic and started eating away the gaskets.

 

With iron head and iron block, its hard to blow them.

 

Took the words right out of my mouth. Haha

[Addicted to eaton]

Facebook? Email? Phone?

 

i have all lol

[karrkrazzie]

i have all lol

 

Well it already has the better UIM and my brother, Nick1234, made sure to tell me to pick up new coolant elbows, he also said something about not byuing the ones from autozone because they suck, so I am going to the dealer in the morning to pick those up and we are doing all the work on sunday. I got new injector o rings, I got 2 kits from napa, and made sure to get the stell reinforced LIM gaskets, Were exactly do you need to put some extra silicone to help fill a gap? Thanks a lot guys for all the help, really appreciate it. Also any ideas on what to do with a stripped thermostat housing hole? A While ago i put in a 180 degree thermostat and one of the bolt holes is totally stripped. I got a little bit of a longer bolt and got it torqued but I am thinking just in case I need to take that off and it wont go back together as it is. I only got about 1.5 turns out of it when i tightened it last time soo. Any dieas would be great

[alec_b]

Once you have the LIM out you should be able to drill and tap the hole to the next size up. Otherwise before you start hit up a member here maybe someone has a replacement LIM lying around and is willing to let it go cheap.

[AL]

I have a spare lower intake I could sell for 45 plus shipping... Has 44k miles on it but I won't be in Toledo to get till this weekend... If you can't wait I have one that has more miles on it (not exactly sure) for 30 plus shipping

[karrkrazzie]

Ill have to let you know... Got everything apart today, and was in the process of putting it back together, and just stopped because that hole is stripped and the bolt wont go back in, and it being sunday night there is nowhere open around here where I can get a tap and a new bolt. I am gonna try and take care of it tomorrow, otherwise I will be needing a new one. I wouldnt mind the one with more miles being that the engine in the car has a 162000 and that one is fine soo, dont see that being an issue. I will keep you posted, thanks

[AL]

Not a problem... I can easily find a box for it and ship it out next day... Just shoot me a PM

[karrkrazzie]

Got the hole tapped and the thermostat is torqued down. Thanks for the offer though, it was nice know I had an alternate option On to the next problem though... I am a moron and when I was trying to replace the injector o-rings i broke off a little piece of the lip that holds the o-ring on it is probably about 20-30 percent of the entire lip that is missing. Do i need to replace this injector now, or will it be okay? The nozzle itself is not damaged at all.

[xtremerevolution]

Got the hole tapped and the thermostat is torqued down. Thanks for the offer though, it was nice know I had an alternate option On to the next problem though... I am a moron and when I was trying to replace the injector o-rings i broke off a little piece of the lip that holds the o-ring on it is probably about 20-30 percent of the entire lip that is missing. Do i need to replace this injector now, or will it be okay? The nozzle itself is not damaged at all.

 

I found a retaining clip that I used in place of that little plastic retainer. Worked perfectly fine for me for a while till I replaced them. I do have a set of L36 injectors for sale with no more than 20k miles on them. PM me if you're interested.