GM Intake Gasket - Engine #2 (is 3 coming)

Ok, I need to vent a little.

I purchased a 1998 Olds LS with 140,000 a month ago for $750. The car is in excellent shape but had a slight tap I couldnt identify. The owner was a retired preacher who just had a lot of money put into the car. New tires and brakes. He also just replaced the upper and lower gaskets for the intake. I of course bought it as is so I knew it was a risk.

After a week of diagnosing, I gave up chasing the problem and figured that it was likely a rod bearing going. The thinking was that the gaskets for the intake were not replaced in time and the oil had been coolant contaminated for a while scarring the bearings enough. I had a few people listen to it and I saw a lot of You Tube videos with cars making the same noise.

I found an engine out of a 99 Bonneville with 75,500 for $300 on Craigslist from a small repair garage that I didnt know existed. I had the whole job done for $750 total which was a great price considering that included the engine.

I drove it for a week and then started losing coolant. The last day it went through about 1.5 gallons and left coolant under the oil cap. No overheat though.

I had the mechanic put the new intake off of the last engine on with new gaskets and the car seems ok now. I have only driven it from the bay and to work today where I am now. He idled it for about 30 minutes, so total I would say that the engine hasn't seen more than couple of hours.

I am going to grab oil and engine flush, on the way home tonight. I will do an oil change ASAP but should I be very scared of the same problem with this engine?

Well you replaced the upper intake so that's done less frequent are the lower gaskets, look for coolant in the oil, if any keep your fingers crosssed.

I just finished with the flush. Replaced oil and filter. Milkshake. Not the worst I have seen, but there must be some mixture of coolant. I guess this is in line with the 2 gallon leak i had the last day I ran it. I havent lost coolant since the replaced gaskets and this is its first oil change since. I will have to wait and see now. I hope the short trips ( less than an hour or two ) with the coolant were not enough to do any major damage.

BTW sometimes you get what you pay for, I have no flywheel cover. There are also loose bolts here and there and the original plugs are still in.

The typical problem with those engines is not the gaskets, but the return plenum itself. That part is made of a composition material that overheats at the point where the EGR valve comes into it and small coolant channels built into it crack leaking coolant into the V of the engine. There are class action lawsuits in nearly every US state and Canadian province over this issue.

I had the job done on mine at about five years of age and cost me around $1,500 by the time it was all done. After that it started leaking again and I put in a tube of granular Prestone stop leak and has been OK since - several years ago that was!

quickcurrent

Everything was going great yesterday, now I had an engine light this morning. Hopefully unrelated but will update if it is. I think I have original plugs and one ify wire, may be a misfire.

P1441 Secondary Emission Control Device? I Looked This One Up And It Must Have Been Set When I Knocked A Vacuum Line Off While It Was Idling. I Reset The Code And No Troubles Yet. New Plugs Are Going In Tonight.

The typical problem with those engines is not the gaskets, but the return plenum itself. That part is made of a composition material that overheats at the point where the EGR valve comes into it and small coolant channels built into it crack leaking coolant into the V of the engine. There are class action lawsuits in nearly every US state and Canadian province over this issue.

I had the job done on mine at about five years of age and cost me around $1,500 by the time it was all done. After that it started leaking again and I put in a tube of granular Prestone stop leak and has been OK since - several years ago that was!

quickcurrent

The Lower gaskets on all of the 3800 series II's are a common leak point, But the Upper intake usually goes first.. I always recommend that when you do the upper intake that the lower gaskets be replaced with the GM updated Aluminum gaskets...

Its also sad how they can charge $1500 for $300 worth of parts, and on these engines removal of the upper and lower intake and to R&R the lower gaskets is not a bad job at all...

I just did the upper intake for a third time in this car after I saw the EGR Passage starting to melt again. This is really an easy job to do. I removed the throttle body to check for leaks to solve a 'lean' code that I couldn't find a solution to. Glad I caught this one in time, the gasket had burn a little along with the plastic intake but not enough to get to the coolant passages yet.

I may need to do the lower intake but I am going to put it off a little.

When I did the upper intake I saw a ton of oil on top of the lower intake. Would this be caused by a pcv valve O-ring? The PCV valve in the intake had no O-ring in it before I did the repair and I just had to replace the valve covers as the rear one had a large crack in it.

When I did the upper intake I saw a ton of oil on top of the lower intake. Would this be caused by a pcv valve O-ring? The PCV valve in the intake had no O-ring in it before I did the repair and I just had to replace the valve covers as the rear one had a large crack in it.


This is normal on all series II L36 Engines.. Its almost the freaky way the Lower and upper are designed.. On the older Series I engines you'll see that Cylinder #1 has the cleanest runner as thats the cylinder that pulls the Mass majority of the PCV vapors... This isn't the case with the Series II... Its really normal no worries there

All these problems with an engine purported by the manufacturers to be "one of the best ten in the world" !!!!

I'd sure hate to own anything below the top ten, hahahahahahaha !!!

I still do feel this is one of the best engines made... After having the issues I have had recently I am losing my faith...

But I have to look at it this way...

My Original Engine gave me 161,000 Miles... It went through a massive intake failure and lived another 80,000 miles...

The way I drive, I am shocked to see the engine even gave me 161,000 miles... Let alone the Trans is still functioning at 171,000 miles... The Major flaws in the 3800 Series II engine was the lower gaskets and the composite upper intake as well as how they had plumbed the EGR stove pipe( Stupidest thing I have ever seen )... I Pulled my original motor out as it had piston slap issues and the PCM was seeing this as Knock and retarding the timing... I'm thinking the Floating wrist pin design wore the bushings causing the pistons to rock a bit more wearing the piston Skirts.... Funny part is that the Bores are beautiful... I am considering rebuilding that motor as it never has any bottom end problems and always had great oil pressure

These are very clean engines, that produce good torque for their size, ample power to move a full sized car... And do it all with very low emissions...


The Buick 3800 is to the V6 world what Chevy was to the V8 world:cool:

If you know to look for problems with the intake plenum gasket then many trouble free miles. I owned an old series 1 3800 and knew well its reliabilty. The other 3800 I owned was a supercharged 95 Olds LSS and that engine was also solid. Fuel economy, power, bullet-proof. These were things always said about these engines.

My problem. I did not ever hear about the intakes being an issue and didn't know what to look for.

I owned 2 Northstar engines. One was a 94 Caddy seville and the other a 95 Aurora. Those were incredible engines in every sense and surely the best I have ever owned. Talk about a bad rap on these engines.

You just need to know what to look for. I put 115,000 on the Aurora myself and got it just over the 200,000 mark before my wife used it to run over another car, literaly. Twenty six miles / gallon and 250 HP was good. Thanks to this site and a few other online forums I knew the secret, CHANGE THE COOLANT and the Transmision Filters.

GM should come up to bat with this Intake issue. I hope they realize why they lose market share every year to the foriegn market.

I honestly couldn't agree more...

GM when they went to the Series III 3800, went to an aluminum upper intake used with their Drive By Wire systems... It has pissed us off to no end... The developed the new aluminum intake and gave us no way to use it on the 3800 Series II engines... But if they had done that it woulds be like they admitted to knowing about their design flaw..

Knowing about the issues is a very good thing, and thats exactly how you make them last longer..

I have a 91 Bonneville SSE, 91 Bonneville LE, 1995 Pontiac Transport... And I have to say these old war horses are beyond tuff... They just keep on going...

I am not a fan of the Caddy 4.0 or 4.6.... But again, if you know of the issues and how to take care of them, you'll drive them forever...

One of the things I love about the 3800 is how clean they stay with oil changes.. This was taken at 155,000 Miles, Don't mind the missing valve cover bolt... That was replaced with another...LOL
http://img.photobucket.com/albums/v294/Jr3800/95%20Bonneville%20Misc/Picture228.jpg

I was at the time installing new valve cover gaskets and new lower intake gaskets with a Dorman upper intake...

GM when they went to the Series III 3800, went to an aluminum upper intake used with their Drive By Wire systems... It has pissed us off to no end... The developed the new aluminum intake and gave us no way to use it on the 3800 Series II engines... But if they had done that it woulds be like they admitted to knowing about their design flaw..

Yeah but where there is a will there is a way. Of course GM is not going to do that or admit guilt. :grinno: But the L26 aluminum UIM conversion to L36 has been done successfully. See link below.

Click here (http://www.automotiveforums.com/vbulletin/showthread.php?t=701174)