Head Gasket?

MassSC

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I'm looking into purchasing a '90 SC which the owner believes needs a head gasket. Will this cause the car to loose antifreeze, or is there a more serious problem? Any advice would be greatly appreciated.
 
I'm looking into purchasing a '90 SC which the owner believes needs a head gasket. Will this cause the car to loose antifreeze, or is there a more serious problem? Any advice would be greatly appreciated.

If a head gasket goes it usually leaks antifreeze in to the oil. Antifreeze will destroy the bearings in the engine if it has been driven or ran in that condition. If the head gasket blew and no driving was done after it blew than there is a good chance the bearings will be ok. It still will need a oil change and the head gaskets changed out. Just be aware the bearings could be gone as well

Ken
 
A blown head gasket can also cause a white cloud out of the exhaust.....

Check the oil first to see if has the milky white coloration.....

If it does, be very careful as this condition could have hurt the bearings.....
 
Most dissapearing anti-freeze is from leaking head gaskets.
some other contributors of the worse kind are, as follows
1-cracked head
2-cracked block

blown head gaskets. and even cracked heads are financaly surviable, but if the block is cracked---you are going to spend some $

As stated in previous post, if it was run much leaking coolant into the oil;then you would be wise to check the bottom end. Anti-freeze will wipe out your bearings (and your O2 sensors)

But what the heck---drag it home and take it apart!
misery loves company
 
Head gasket, cracked head or cracked block

What would the average cost of the following repairs be?

Head gasket?

Cracked head?

Cracked block?
 
What would the average cost of the following repairs be?

Head gasket?

Cracked head?

Cracked block?

you going to be doing the labor yourself?

if your paying someone else.....

look for about $1,000+ to have the headgasket done...
if you have a cracked head..it depends if your going to replace it with better heads or find a set of stock heads...to have that replaced your probably looking at around what it would cost to have a headgasket done....

and if you have a cracked block...you need a new...SCP sells a long block for $1,8xx i believe....

if you can do it yourself then your just paying for parts...
 
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Update

I bought the '90 SC auto for $500 and towed it home last Sunday. How do I find out exactly what's wrong with it? I was told it needs a HG replacement and I'm up to the challenge, but how can I find out if there is something more serious?
 
If you are not familiar with how the engine was operating before you bought it, then you are in for a challenge. You may beable to pull some info from the KEY ON ENGINE OFF diagnostic.

Pull the plugs and see whats been going on.

Drain the oil in to a clear container, this will allow you to see how much oil is in the oil, if it has had a coolant leak into the oil. The antifreeze/water will have settled into the bottom of your oil pan, and will come out first. If there has been muck water in the engine during operation, then the bearings could be shot. If you pull a rod cap off you will know for sure. Don't forget cam bearings in the list of considerations.

If you pull the heads you can check for head gasket failures, heads can be pressure tested for cracks. The chances of a cracked cylinder wall is also a consideration.

If things don't look to scary---throw on some head gaskets anf fire it up!
 
If you do a leakdown test before tear-down, that can tell you where it's leaking, also condition of rings and valves, but you're going to find that out anyway on the tear down. Leakdown test rather difficult on SC with the tight fit, all the tube routing. I recently bought a '91 SC with the same problem for $300. Gaskets(top end set) and the stud kit>(highly reccomended) from Bill @ supercoupe performance set me back close to 300, other miscl. brought parts to around 4.You're also going to need the teflon intercooler tubes tape Labor was 450, which I considered fair. If possible, whether you or a shop does the work, have a factory service manual, it really helps. So after repair, car runs great but still gets a bit hot. Found very small antifreeze leak at thermostat housing. A lot of times, something else in the cooling system, radiator, water pump, etc. can cause overheating, which can lead to blown headgaskets. A lot more common on 89-93 SC's though.It's pretty rare for cracked heads or block to be the cause. When something breaks, I like to find what made it break in the first place. Usually a little problem , not taken care of, leads to a bigger problem. Gotta fix them all. Just tear her down, see what you got, and order the parts. While its apart, its a great time to check the cylinders for wear, ridges or scoring, and get the valves done if it needs it. Take everything off as an assembly wherever possible, charger, TB, etc.
Mine had blown gaskets on both sides, pass. rear cyl. and driver side middle.
Still have to replace the O2 sensors, to pass smog, too.
Best of Luck with repairing your SC, hope this helps......
 
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