Bad luck with GM 3800 motor!

[Trav]

Originally Posted By: aquariuscsm
I had an `87 Olds Trofeo and sold it with a lil over 300,000 to buy a 3000GT. My dad gave his `90 Olds Delta 88 to one of my nephews with well over 500,000 on it. Both ran flawlessly,and the Delta 88 still does to this day.

Were the earlier 3800`s better than the Series II and III? They seem to be more durable and didn't have all that plastic stuff on them.


No they were not as strong internally they just aluminum intake and plenum.
I got both my Gen II with well under 100K on them and the first thing i did was the LIM gaskets and an improved plenum with modified EGR chimney for the non SC engine as preventive maintenance.
Both showed signs of impending gasket and upper plenum failure also on the non SC engine.

OP i don't know why you had a rod failure, stock SC rods are good to some pretty impressive power levels.
Try pulling the pan and bearing shell to get a better idea what happened before yanking the engine before the knock damages the crank if it already didn't.

 

[pbm]

Originally Posted By: heyu
Originally Posted By: crazyoildude
it was dex cool.... i see it every day


+ 1 agreed 100%



It seems strange that GM still uses Dexcool and from what I've heard Ford is now using a version of it.
Also, most of the AMAM like Prestone and Peak are 2EHA coolants.

While we know that 2EHA is a plasticizer..it was STUPID of GM to use so much plastic with a coolant that eats plastic.....bad engineering.

 

[Trav]

Originally Posted By: pbm

While we know that 2EHA is a plasticizer..it was STUPID of GM to use so much plastic with a coolant that eats plastic.....bad engineering.


It eats plastic? I wonder why the plastic jugs are not all eaten away on the shelf even after 6 years in my garage.

It wasn't so much a issue with plastic as it was from a poor silicone seal design on the plastic gaskets.

The issue with the plenum was EGR burn though not dexcool damage. With the improved plenum and aluminum frame gaskets with improved sealing material there are no problems even with the plastic plenum and dexcool.

 

[dwcopple]

Originally Posted By: heyu
Originally Posted By: crazyoildude
it was dex cool.... i see it every day


+ 1 agreed 100%
+2 agreed 200%

 

[zzyzzx]

Exactly what plastic elbows are you referring to? Would I have them on a 1999 Alero with the V6 engine?

I already did the LIM gasket, and it was a PIA.

 

[Bryankkkk]

I also had a 3.8 throw a rod thru the block. Had a knock when I bought it lol, got to drive it for 1 minute before it let go. Got it on video and have a album of the tear down D:

 

[bdzik]

my wife's 2001 grand prix gt was totalled on monday,because of an engine fire. lucky the car was still insured.

 

[sciphi]

Originally Posted By: pbm
Originally Posted By: heyu
Originally Posted By: crazyoildude
it was dex cool.... i see it every day


+ 1 agreed 100%



It seems strange that GM still uses Dexcool and from what I've heard Ford is now using a version of it.
Also, most of the AMAM like Prestone and Peak are 2EHA coolants.

While we know that 2EHA is a plasticizer..it was STUPID of GM to use so much plastic with a coolant that eats plastic.....bad engineering.


IIRC it was the old version of Dex-Cool that ate plastics. Not the new version they've used for a while now. They've fixed that issue, supposedly.

 

[SteveSRT8]

Originally Posted By: Trav
Originally Posted By: pbm

While we know that 2EHA is a plasticizer..it was STUPID of GM to use so much plastic with a coolant that eats plastic.....bad engineering.


It eats plastic? I wonder why the plastic jugs are not all eaten away on the shelf even after 6 years in my garage.

It wasn't so much a issue with plastic as it was from a poor silicone seal design on the plastic gaskets.

The issue with the plenum was EGR burn though not dexcool damage. With the improved plenum and aluminum frame gaskets with improved sealing material there are no problems even with the plastic plenum and dexcool.


I wonder how many thousands of years it will be before folks quit with the Dex [censored]. It's all over people. And it wasn't a Dex issue anyway, it was a gasket issue.

Haven't seen this since the 90's. Let it go...

 

[LeakySeals]

08 3800 Series III here. In addition to having the factory valve seal defect, I finally rid myself of that nasty Dex-Death after 10k of drain and fills and RMI-25! This was how it looked at 70k. Had to pressure spray the expansion tank after every drain and fill (6 total) to get that Evil Dex out of that engine.

After pressure spray

It would not let go, bloomed like algae. Terrible stuff.

 

[mechanicx]

Originally Posted By: zzyzzx
Exactly what plastic elbows are you referring to? Would I have them on a 1999 Alero with the V6 engine?

I already did the LIM gasket, and it was a PIA.


The Alero would have the 3.4 60 degree V6. The plastic elbows are on the 3.8.

 

[ZZman]

It seems they either run forever or fail.

My mechanic is going to put a used motor in it but change out all the gaskets first and then bolt on my supercharger.

He said maybe it had been overheated before or oil starved. I had changed the oil after I bought it and had about 4,000 miles on the oil. No oil light came on. No coolant issue seems to be present that I could tell and oil looked normal.

Maybe a wrist pin issue or something?

 

[Trav]

Wrist pin would have a double rap. Something probably happened long before you got the car.
Still its worth having a look before tossing it, if nothing else it might be a good rebuildable you can mess with and build it even better.

 

[heyu]

Originally Posted By: SteveSRT8
Originally Posted By: Trav
Originally Posted By: pbm

While we know that 2EHA is a plasticizer..it was STUPID of GM to use so much plastic with a coolant that eats plastic.....bad engineering.


It eats plastic? I wonder why the plastic jugs are not all eaten away on the shelf even after 6 years in my garage.

It wasn't so much a issue with plastic as it was from a poor silicone seal design on the plastic gaskets.

The issue with the plenum was EGR burn though not dexcool damage. With the improved plenum and aluminum frame gaskets with improved sealing material there are no problems even with the plastic plenum and dexcool.


I wonder how many thousands of years it will be before folks quit with the Dex [censored]. It's all over people. And it wasn't a Dex issue anyway, it was a gasket issue.

Haven't seen this since the 90's. Let it go...


Let it go ? fraid not , i will say my point and have my right to do so ,Just because your a paid donor does NOT mean your facts are always right

 

[SteveSRT8]

Originally Posted By: heyu
Originally Posted By: SteveSRT8
Originally Posted By: Trav
Originally Posted By: pbm

While we know that 2EHA is a plasticizer..it was STUPID of GM to use so much plastic with a coolant that eats plastic.....bad engineering.


It eats plastic? I wonder why the plastic jugs are not all eaten away on the shelf even after 6 years in my garage.

It wasn't so much a issue with plastic as it was from a poor silicone seal design on the plastic gaskets.

The issue with the plenum was EGR burn though not dexcool damage. With the improved plenum and aluminum frame gaskets with improved sealing material there are no problems even with the plastic plenum and dexcool.


I wonder how many thousands of years it will be before folks quit with the Dex [censored]. It's all over people. And it wasn't a Dex issue anyway, it was a gasket issue.

Haven't seen this since the 90's. Let it go...


Let it go ? fraid not , i will say my point and have my right to do so ,Just because your a paid donor does NOT mean your facts are always right


Well, the facts are in. Maybe one day you'll get it!

 

[Trav]

Originally Posted By: heyu
Let it go ? fraid not , i will say my point and have my right to do so ,Just because your a paid donor does NOT mean your facts are always right


Well unless you can explain why it doesn't eat through the cheap plastic jugs after 6 years or the coolant overflow bottles i would say your point isn't correct either.

 

[javacontour]

I don't know which versions they were using in1975 and 1987. My 75 jumped valve timing and the 87 did the same to the point where it would not run.

A very smooth, powerful engine, but I was lucky enough to have two with internal mechanical failures well before the mileages others say they are getting from this family engines.

 

[SteveSRT8]

Originally Posted By: Trav
Originally Posted By: heyu
Let it go ? fraid not , i will say my point and have my right to do so ,Just because your a paid donor does NOT mean your facts are always right


Well unless you can explain why it doesn't eat through the cheap plastic jugs after 6 years or the coolant overflow bottles i would say your point isn't correct either.


Trav, it never ceases to amaze me how folks hang on to their hate. This Dex thing has been settled for ages. It was a bad thing for sure. But it's OVER...

Some of us are having real difficulties with moving on.

 

[mechanicx]

To say Dexcool or 2eha is a plasticizer is sort of half the story at best. All hot coolants especially OAT coolants and non-silicated are plasticizing to a degree of some types of plastics. Some plastics have the same service life with Dexcool. So Dexcool and 2eha being a plasticizer is mostly irrelevant.

It's more a gasket issue. Even with non-oat silicate green coolant, those gaskets would leak. Maybe not as soon or as bad, but close enough to where whatever difference is little matter.

 

[mechanicx]

Originally Posted By: Trav
Originally Posted By: heyu
Let it go ? fraid not , i will say my point and have my right to do so ,Just because your a paid donor does NOT mean your facts are always right


Well unless you can explain why it doesn't eat through the cheap plastic jugs after 6 years or the coolant overflow bottles i would say your point isn't correct either.


Or even the hot side of the plastic radiator tanks. when they say plastics I think they mean elastomers "rubber" gaskets instead of polymer or plastic. But that's the thing not all elastomers react the same to Dexcool or any OAT coolant.