upper intake problem on '97 LeSabre

[formzy]

I bought this car in Nov. '03 and shortly thereafter heard about the upper intake gasket problem. Have posted in the past about this and have kept a close eye on my coolant levels. Recently I have noticed and smelled the anti-freeze starting to leak more on top of the trans under the throttle body and assume the problem is getting worse.
Very small leaks have occured in the past 4 yrs. and then seemed to stop. I have the Ken-co kit which I think is the best way to go and shop manuals etc. I have a few questions for those that may have done this job already.

1.When removing the then replacing the fuel ijector rail do you have to replace the o-rings?

2. When removing the upper plenum do you leave the throttle body assembly attached or remove it?

3.I assume no need to drain anti-freeze? Am I wrong?

4.No sealer is to be coated on new gasket?

5.Also my gasket kit has 2 0-rings and a couple of other gaskets- one for the throttle body etc. Do you guys replace these also at this time?

Looks like I need to do this job soon because puddles are getting larger although no internal (or large amount) coolant is being burned off. (Good levels).

Any other tips would be greatly appreciated. Thanks, Formzy

[maxwedge]

I would replace the upper intake not use the Kenco kit (I assume this is the epoxy based egr kit?), the Dorman set comes with everything, yes drain the coolant, yes the TB comes off especially to inspect the egr passages, good practice to repl. the injector seals. No sealer, the gasket is built into the manifold. Try doing a site search here for additional details, plenty of info.

[Carwhiz]

Before proceeding with upper intake replacement, be sure your lower intake isn't leaking as well. not as common, but you really hate to have to go back and replace the lower intake gasket in the near future. look closely where the lower intake meets the block, if any seepage is found here, your lower intake is leaking as well. Assuming only your upper plenum is leaking, it is recommended to replace the fuel injector o-rings...but seldom do people do. examine the o-rings very carefully and lube them up with a fluid. many people have different recommendations on what to use, liquid white lithium grease is which i prefer. I have done dozens of 3.8L and I have yet to replace injector o-rings. As far as throttle body, I leave attached to plenum and don't even bother with it, unless you are ambitious, but it is not needed to remove from plenum. you loose very little coolant while removing the upper plenum, so no need to drain. no rtv is necessary for upper manifold gasket. the gasket kit you received probably contains new o-rings for pcv valve.

[happydog500]

1.When removing the then replacing the fuel ijector rail do you have to replace the o-rings?

*Why would you not want to? Not that hard and just a few minutes. I didn't have to but paid the few dollars and replaced them while I had them in my hand. I didn't take them out of the fuel rail, so I only had to get the bottom ones replaced. They came in pairs so I needed 3.

2. When removing the upper plenum do you leave the throttle body assembly attached or remove it?

*I spent the 45 seconds to take it off so I could clean the TB better. You don't have to.

3.I assume no need to drain anti-freeze? Am I wrong?

*Yes, see + at bottom of post.

4.No sealer is to be coated on new gasket?

*No, not on the UIM.

When I was thinking of doing mine, I hated the idea of having to do both upper and lower. I herd of people doing the upper, then very soon after the lower goes out. They have to do what they just did all over again.

Please, when doing an UIM, you have everything off, your right there. Spend a little time (compared to having to do it over again) and do the LIM gasket also.
+For the LIM, you will need a little antifreeze.

P.S. After looking at mine, I found my intake was OK, it was the gasket that was bad.

Doorman is over priced IMHO. I've had very good success with the APN.
http://www.automotivepartsnetwork.co...product=229679

[formzy]

Thanks for the tips!

Never thought that the lower intake gaskets were a problem but makes sense to check them out when top plenum is off. I'm looking for coolant seepage or leaks against block and possibly on both sides of manifold?

It looks like this is made out of aluminum (Lower intake)and therefore would be lighter to pull. One man job I assume? Any special gaskets or new style you would recommend if I need to do the job?

Hopefully it's not leaking. Not really looking forward to pulling manifold but would also hate to go back and do over again later. I don't know why many are against the Ken-Co kit as even one post for the replacement plenum offers it as an alternative. I already have the Ken-Co kit so leaning that way unless convinced otherwise.

Thanks, Formzy

[happydog500]

One more thing I just remembered. On the 97 model, there is two different gasket sets that it could be. No way to know until you get the manifold off. Make sure both are available at the time you do it. That way, when you get it off you can go get the one you need.

I used Fel-pro Gaskets. GM has new, metal gaskets that are supposed to be pretty good. I didn't use them because the original problem is the GM gasket. I just couldn't get myself to trust them again on the gasket.

Mine was barley leaking, just a few drops. When looking at the UIM/gasket, it was barley leaking. It wans't until we got the Lower off that we saw the crappy gaskets GM used on these models. It was leaking into the air and oil passages.

I showed it to a Toyota macanic I know, he just keept looking at it and saying he had never saw anything like it. If I could ever figure out how to post photos here, I could show you.

I had no signs of antifreeze getting in the oil. Only saw that it was once I got the Lower off. That's why I hope you do the lower also.

If you put the lower on, do a couple dry runs of practicing putting it on slowly. The first time I did it, the gasket slid down when the LIM was set down. Just takes a couple times of setting it down to get the hang of it.

Also, there is a plastic elbo that breaks when you take off the LIM. Lots of threads here say it's a dealer only part. I broke mine off on a Sunday. I sat around for an hour, mad I couldn't get it till tomorrow. I decided to go to the store (Shucks) to make sure. Well, what do you know, they had it!!!!
Chris.

[CarDude225]

A couple of quick questions while we are on the subject, but not to derail the thread...

1) Before pulling the lower LIM to change out the LIM gasket, does the timing chain have to be removed, and all the valves?

2) One more question.
What is the typical cost for a professional to replace the LIM gasket with Fel Pro, and the UIM with Dorman/APN kit? Is this what I think it is about a $500-$800 job, start to finish, parts and labor?

I'm not sure I would be comfortable with doing the LIM and UIM myself as I'm an alternator, waterpump, battery, filters, disk brakes, electrical kinda guy. I have never worked on an engine itself except in 2006 when I COMPLETELY rebuilt my 150hp 2 stroke Yamaha boat motor (still running!).

[BNaylor]

Originally Posted by CarDude225

A couple of quick questions while we are on the subject, but not to derail the thread...

1) Before pulling the lower LIM to change out the LIM gasket, does the timing chain have to be removed, and all the valves?

No. And unlike the GM 60 degree engines on the SII 3800 90 degree engine no rockers or pushrods need to be removed so no valvetrain work per se. Note that there is a plastic 90 degree elbow (heater bypass) that should be replaced along with the 2 o-rings. The tensioner assembly must be removed to replace this or get it off the LIM.

[happydog500]

You have more experience then I and I was surprised, shocked how easy this was.

Many people with no experience have posted here that they did it. It's scary to start, but after you will be proud of yourself.

I have a lesabre. I went to the Bonneville and other cars with the same 3.8 motor forums. Kind of disappointed that the forum with the least stuff is the Lesabre.

One had a person who posted steep by steep photos as he went. That gave me the confidence.

When I first started racing Motocross, to have the main barrings changed I would take the motor out, strip it down, take it to the shop. They would split the case and change the barrings. I would then put the top end on and put the motor back in.

You might be able to do the same. Take apart the stuff until you get to the LIM. Have someone do that part (I think you'd be proud of yourself after if you did it), then you finish. It could save some $.

Just a thought that might help.
Chris.

[CarDude225]

Wow thanks for the info. No valves or rods; now this sounds like it is getting easier by the minute.

Happydog, you don't happen to have the link to the post in the other forum with the step by step and pictures do ya??????????? That would be sweet to take a look at beforehand.

[happydog500]

Hay, on the manifold, you just take the bolts off and lift. Nothing else.

Not off hand. I think it's here at automotive forums in the Bonneville. It may be from a link of some Bonneville Club. It keeps coming up when you look.

I wish I could be more help right now. I am so stressed out. I'm getting ready to catch a plane to see my dad for three weeks. I will be leaving in a smaller airplane, flying right through a big snow storm. I was told we will not be able to see anything, flying by interments.

If I have time I will try to find some info. One post was a kid who did it without any experience.

Search for intake manifold in Park Avenue, Bonneville, LeSabre forums.

Chris.

[creslevi]

Haven't studied this whole thread, but would urge you to check the water pump bypass fitting behind the Alt. some of them are vinyl/plastic and they crack, luckily for me mine broke in the driveway while changing my Alt, easy fix but you must remove the Alt, if you don't have the decal for the belt routing, take a digital picture before you remove the belt, you will be glad you did, My 94 had no decal !.

[HotZ28]

Originally Posted by creslevi

Haven't studied this whole thread, but would urge you to check the water pump bypass fitting behind the Alt. some of them are vinyl/plastic and they crack, luckily for me mine broke in the driveway while changing my Alt, easy fix but you must remove the Alt, if you don't have the decal for the belt routing, take a digital picture before you remove the belt, you will be glad you did, My 94 had no decal !.

Let’s not confuse the Series I coolant bypass with the Series II (96-up) bypass, which has the elbow from the manifold to the tensioner, this is entirely different from the Series I under the alternator bypass!

[formzy]

Some sites and talk about replacing the lower intake manifold says to replace the bolts with new ones. Is this necessary? How many have done the job and felt it was necessary to buy new LIM bolts?

Thanks

[maxwedge]

The bolt issue usually applies the 3100 intake gasket situation, it can never hurt to replace prveiously torqued bolts but I haven't done this yet, I 'd seal the ones onside the intake though as oil can work it's way up the threads.