3800 Using Coolant

[bigdog9191999]

Being a 3800 I would guess lim gaskets. They don't usually eat head gaskets, although water pump is that bad to do either. I would say the upper intake could be cracked, but that should be aluminum that year.

 

[Matthew Jeschke]

I should put up a bet to see who can guess what it ends up being haha I don't know what it is about these v6 Chevy motors but the cooling systems are so damn temperamental. I've owned a couple 3100,at least this one 3800, and a 4300. They were all awesome little motors aside from coolant issues. Cannot say I had any issues other than idiot shop who worked on 4300 to change fluid though.

 

[bigdog9191999]

This is but a fraction of what I have had with these.

 

[Tonyrodz]

I had an 89 Bonneville sse with the 3800 in it. Loved that car. I never had a problem with the motor, except for a seized alternator, but the rest of the car was nickle and diming me to death. I wound up giving it away to someone.

 

[Matthew Jeschke]

@Tonyrodz For a while my dad drove the supercharged Bonneville...... OH WAS THAT CAR AWESOME! The little supercharged 3800 drivetrain is sooooo cool.

DANG! @bigdog9191999 that's a few!

I certainly like the engine architecture MUCH better than any of the imports. No belts, no overhead cams, or any of that BS to worry about.

SUCCESS, there is a leak! It's hard to see exactly where with the engine mounted sideways though. I may get some UV dye and dial in the location further... But I'm guessing the water pump? However, where's the weep on this thing... Isn't it behind the pulley? I'd suspect it would leak from the weep. The puddle is more towards backside of engine and above accessories.

Stain on Cardboard.mp4

drive.google.com

 

[Tonyrodz]

@Tonyrodz For a while my dad drove the supercharged Bonneville...... OH WAS THAT CAR AWESOME! The little supercharged 3800 drivetrain is sooooo cool.

DANG! @bigdog9191999 that's a few!

I certainly like the engine architecture MUCH better than any of the imports. No belts, no overhead cams, or any of that BS to worry about.

SUCCESS, there is a leak! It's hard to see exactly where with the engine mounted sideways though. I may get some UV dye and dial in the location further... But I'm guessing the water pump? However, where's the weep on this thing... Isn't it behind the pulley? I'd suspect it would leak from the weep. The puddle is more towards backside of engine and above accessories.

Stain on Cardboard.mp4

drive.google.com

Doesn't look like it's gonna be a fun job.

 

[Doubeleive]

water pump leaks can be hard to find, probably have to use a flashlight and one of those angled telescoping mirrors from the autoparts store to find the exact spot

 

[bigdog9191999]

I have owned probably close to a dozen different ones over the years, and parted and scrapped at least twice that, and worked on others for them, so to say I am familiar is an understatement.

 

[Matthew Jeschke]

@bigdog9191999 have you had a water pump failure on one before? If so, where did it leak from? I suspect the pump, but it's not leaking from where the bearing is (or doesn't appear to be).

 

[Matthew Jeschke]

One step closer, the heater core elbow directly above pump has water under it. I'm not sure if it's the elbow or the gasket.

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Hopefully UV dye can sort it out. I recently replaced those elbows with aluminum *ahem* Dorman parts. I like that they are metal instead of plastic. However, Dorman doesn't exactly inspire confidence. I really cannot figure out how to easily distinguish leak from the elbow or leak from the intake gasket. They are so close together. I don't appear to be leaking anywhere else between the upper and lower intake, and there's no coolant getting in the combustion process (at least judging by exhaust).

I have also regularly maintained my coolant system. Changed fluids, etc. People seem to think aged DexCool coolant corrodes the gasket material. Right now though, I'm running mostly water because of this issue.