Headgasket(s) are gone....I think

89SCK@t

Registered User
Yup. I took the 93SC on its first 10 mile drive in a month. Hell, its first drive in a month.

I took it on base to change the oil, plugs, wash and wax it. I did the wash first, and was pulling it up the ramp for the lift at the auto hobby shop, and I noticed a little puff of smoke. Grayish colored. Changed the oil, dropped the car and was putting oil in it, when I noticed the overflow had a lot of black specks in it.

I went to check the rad cap...oil gunked all over the cap. I didnt even bother to change the plugs, and drove it home. At the stop light right before my house, I was making clouds for the sky.

I dont get it. There was no coolant in the oil, but it is burning coolant, and there is oil in the coolant...It never overheated. The fan kicks on at the R on the temp gauge, kicks off when it get to the O. It doesnt get driven hard, except for the occasional full boost run to get on the highway.

The sad thing is that my 93 only has 48652 miles on it.

If this is the case, then I guess I know what I need to do. Now the only problem is debating on whether or not to keep it stock and original...Not only that, but now I can use my headers.:D

Stephen
 
Unfortunately, the main issues with the headgaskets are related to corrosion caused by the close position of a coolant port and the rear cylinder walls. The standard fiber/graphite composite head gaskets get worked on over time by the coolant flow, causing the coolant to permeate the passage opening and start corrosion of the fire rings.

I feel that on a standard motor, with no real power improvements (say keeping it under 300rwhp) I think the standard felpro replacement head gasket can give a good long service life if you just stay on top of that coolant. I'd highly recommend switching to something like the Evans coolant to remove all water form the system. But if you want to stay with a mix, monitor the PH of the coolant closely to ensure the corrosion protection packs are working.
 
I feel for you mine blew the same way. I started the car in the morning and as soon as I went to take off I knew they were done. No water in the oil but I had oil/antifreeze shooting out of the overflow tank
 
Damn...I really was hoping that it might have been an intake gasket or something...Oh well.

Now I have to collect parts to get the project....:rolleyes:
 
I'm in the same boat as you with my 89 SC @ 90,000 miles. I have recently noticed the black specs in my coolant oveflow and on my radiator cap. I'm using some coolant but I don't see any white smoke in the exhaust yet - probably just a matter of time.

I had a engine rebuild shop do a pressure check on the coolant system. They don't do the typical leak down test. They measure the pressure with a gauge on the radiator and correlate the pres with coolant temp. They say if there is an exhaust leak from the combusion chamber into the coolant the pressure will rise proportionally to the exhaust leak. They told me it was reading ~4 psi above what it should read at a given temp. They said I still had a little time before the gasket would "blow" completely but I know this is impossible to predict. I'm looking for someone to replace the head gaskets but their price was a little steep. They wanted $1500 to do the gaskets and replace the valve seats.

I have no doubt they would do a good job - they rebuild engines for the Mopar Mile High Nationals at Bandimere. If I had the time I would do the job myself - but I don't.
 
Why replace valve seats? If they're gonna do that I'd look at options for a bigger intake valve and have a minimum 3 angle valve job, and a 30 degree back cut on the valve would be nice. That'll add cost of course.

If they haven't worked on SC's before, that's a fair price, as they'll spend quite a bit of time that they didn't intend to just getting to where the can pull the heads off.

If they have done SC's before it's probably a tad high.
 
Why replace valve seats? If they're gonna do that I'd look at options for a bigger intake valve and have a minimum 3 angle valve job, and a 30 degree back cut on the valve would be nice. That'll add cost of course.

If they haven't worked on SC's before, that's a fair price, as they'll spend quite a bit of time that they didn't intend to just getting to where the can pull the heads off.

If they have done SC's before it's probably a tad high.

The engine is using oil - thus the recommendation to replace valve seats since they didn''t think oil was getting past the rings.

I know they have no experience with SCs - that's why I'm still looking.

Will continued leakage of coolant into the combustion chamber cause corrosion to that part of the engine assuming it is vaporized and doesn't make it to the crankcase?
 
I think they were talking valve seals, not seats. Seats are what the valve rests on when it's closed. Seals are near the end of the valves up by the rockers and seal the valve stems to keep oil from the top of the heads from making it's way down into the combustion chamber.

I pulled the engine and trans out with my 5 speed as one unit. Not sure if the auto will do it. There isn't much of a problem though pulling the trans out the bottom though. You'll need to get the front part of the exhaust out of the way to do either.

Note that you can also unbolt the k-member and lift the body off the engine trans package if you have access to a frame lift.
 
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