View Full Version : Gasket blown - other work while there?

06-10-05, 07:38 PM
The diagnosis is that my 1996 STS with 170,000 miles does have a blown headgasket as per a test for exhaust gases in the coolant. Now I'm faced with a decision on repair. While the engine is out, are there other items that make sense to tend to in order to avert a potentially expensive problem later?
I've seen posts regarding doing the following:
1. Replace HVAC cover and clean and service AC Evaporator.
2. Replace lower oil seals

Does that make sense? Anything else one would advise to check or replace while engine is out?

06-10-05, 08:51 PM
Make sure ALL the head bolt holes get Timeserted.

06-12-05, 05:25 PM
I had a 96 Eldo that blew a head gasket. I opted to have it repaired to the tune of $2,500. The "repair" lasted roughly 30,000 miles before it blew again. Turns out the block warped. My choice was spend 3 to 5K replacing the block or engine or just dumping the car. I worked a trade deal for a 2000 Escalade - which my wife loved and I could live with until I could find another car.

As much as I loved my 96 [I've owned several Eldos] you have to make a decision based on common sense somethimes. The cost of repair was going to exceed the value of the car so it went.

I've now recently picked up a 2001 Deville with 48,000 on it. Great car. Hope it's solid - can't find anything wrong with it but just the same, I'm always leery of a used car.

06-12-05, 05:42 PM
Searching around the forum indicates that the "gases in the coolant" test is not conclusive. Several guys advise either applying 120 PSI to the cylinders (while at TDC) and looking for bubbles in the surge tank, or applying 15 PSI to the surge tank for several hours and then with the plugs removed, crank the starter to see if moisture is blown out of any of them.

In any case, with that many miles on it you likely have some oil leaks that you want to eliminate, which means replacing seals and gaskets that you cannot normally access. I guess my opinion is that if you are going to go that far into it, you might as well come out with something that will make you happy for a reasonable amount of time. And certainly check the block/heads for warpage...

06-12-05, 05:53 PM
With 170K miles, I'd be very tempted to replace the whole engine.
Even so, I think you are wise to consider some preventive maintenance while the engine is out. You've already spent a lot on labor at that point. I'd at least factor in an oil pump, timing chain and freshen up the head with new valve seals and valve grind.
How long do you plan to keep the car? Do a cost benefit analysis. But make sure it's blown first.

06-12-05, 07:54 PM
I had a 96 Eldo that blew a head gasket. I opted to have it repaired to the tune of $2,500. The "repair" lasted roughly 30,000 miles before it blew again.
Where ALL the headbolt holes Timeserted? If not, that may be the reason for the second failure. I have never heard of a warped block and would think that if that where the case it would have failed lomg before 30K.

06-15-05, 08:41 PM
not much more time, the gasket will come in the head set, and the other old gasket is probably not far from the bad one-- I have seen this too many times!!!
mill both heads, or at least have the machine shop check them for flatness. I think max warpage is around .002"

oh yeah, do the crankcase seals, oil pan seals, and front and rear main seals. it'll save lots of time later on.

06-15-05, 09:40 PM
What about doing the head gaskets if you need new oil seals??? I've been told that the oil seals are somewhat on their way out (even though I dont have a drop od oil on the ground.) My warranty will expire soon and it will cover those oil seals. I'm wonderig how much extra I will have to pay out of pocket to do the head gaskets and timeserts?? I also wouldnt mind having them replace the all too familiar degraded blower housing while the engine is out. I know I will have to pay for those things other than the oil seals but I am under the impression that most of the labor involved is getting the engine out of the car.

I'm also afraid of the old saying, "if it ain't broke then dont try to fix it."

96 ETC 93,000 miles