Hold on a second.....have you been losing coolant? I've never seen or heard of a cracked block on a 3800. Nor a cracked head for that matter. I'm betting a cracked/eroded plastic upper intake. That would explain the milky oil, but wouldn't necessarily explain the clunking noise, unless you have some rust damage in the oil pan.

We just bought this car from a friend who tows cars..We got this for a great deal..It wouldn't start..We figured it was a timing chain..It turned out to be the flywheel...It must have been losing coolant because the radiator had a hole in it...We replaced that also...My husband said that the wristpin has worn out and cracked the cylinder wall...

If that'* true, it'* the first failure of it'* kind I've ever heard of. Read the "Vin K" sticky at the top of this forum. The upper intake failure is the common source of milky oil, and that damaged oil can cause lifter clatter, as well as rusting out crank bearings (and rusting wristpins). The intake may very well be the root cause.

I'd love to see this cracked block, as the only damaged block I've seen is one from Thrasher (after they pumped a tremendous amount of power through it).

My hubby read about the series 2 intake problem..He is gonna see into that...That very well may be our problem...He is usually pretty good as fixing vehicles...What would be a good way of flushing out the motor if it turns out to be the problem? Also would a intake from a series 1 match up to this one?







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1995 Bonneville SE 3800 series 2

A series 1 intake won't fit, but the new GM intakes (expensive) and the Dorman replacements (cheaper) will fix the problem. They are an improved design.

The best thing you can do right now is change the oil asap. The amount of rust damage will depend on how long that water has been in the oil.

Change the intake (if it'* bad), change the oil today if you can, and run it for a day or two, then change it again.

Ok we took the intake off..There are no visible holes inside..but my husband thought about something after I had mentioned this to him...The line that runs into the intake (I think it'* the EGR line??) was full of antifreeze...Let me ask something else...One of the reasons he though he had a cracked block was because he felt water spraying off the motor(like a mist), He could not find exact spot where it might be coming from...Is this a sign of a bad intake also..or do we possibly have another problem elsewheres?....Like I said we bought this car for $400 from a tow company...A friend of ours owns it and he gets all the interstate tows...Once no one claims them, he can sell them. It is in super great shape as far as body and interier..Very clean, the only problem is that the headliner is falling ..This is defiantly worth fixing, but it'* driving me nuts!! LOL Is there a way to test the intake to see if it is bad before you buy a new one?

I'm not a guru gearhead, but if the coolant passage in the upper intake has ruptured, a cooling system pressure test might tell you, assuming there are no other cooling system leaks.

-b

That sounds like the classic failure. The plastic erodes near the EGR port, and 'violates' a coolant passage. If you look at the pics in the "Vin K" sticky at the top of this forum, you'll see it. If you had coolant in the EGR tube, that'* your problem.

Coolant misting off the engine could be coming off the belt.....from the water pump. Check to see if you have coolant weeping from the bottom of the water pump, or from the bypass hose that connects from the top of the water pump to the lower intake.