89 caddy head gasket!!help

[kitty fischer]

 I just had a well respected radiator shop repair a leak and flush/ refill/pressure test the cooling system on a gem of an
89 DeVille.  Im keeping the car going for sentimental reasons so my 90 y ear old dad will have his car under him
as long as we can ( I drive btw ).  
After leaving the shop at night ,20 yds later, the engine started making noises and was weak in performance.  So
much so I pulled it over and had it towed in the morning.
I practically  could not drive the final 30 feet into a space at
the mechanics lot.
QUESTION: Can major work on a rad cause an already
barely leaking head gasket to go postal?   They reported a
very small amount of engine gases in the water but recco
mended Bars Leak to buy a few more months with the car.
Have I been taken to the cleaners.  
QUESTION 2: What hoses, grounds, devices may have
been disturbed to cause the weak rough engine SO
Quickly after servicing the rad.   By the way my dad has
owned over 20 caddies and if we could bury him in one it
would be his 65 ( I know you understand now) kitty

[JIM CLC # 15000]

11-19-05
Kitty, Sorry to say, but the radiator-shop most likely did nothing wrong! But, Its embarrassing to admit but I had a leak repaired on an 86 SDV and after driving about 12 miles home, something told me to check the oil level, the crank-case was over-full and the radiator was low. The intake manifold gasket had gave away. To make a log story short, The machanic at the Cadillac shop said to spend $500.00 and trade it off as it wouldnt go more then 90 more days.(had 93K on the odometer at the time. Replaced 4 valve lifters and traded it off when the odometer read 220K+ miles.
Good Luck, Jim

[Barry Wheeler #2189]

Hi,
It is possible that if the car was barely leaking, that adding pressure to it may have caused the gasket to break. From what you say happened, it sounds just like what my 86 did on the way to work years ago. When they let go, it happens all at once. I believe there is one flange that is very narrow, and that may have been what let go.  If your father still has such a love for the car, bite the bullet and get a replacement engine. My 86 never seemed the same after they replaced the cam, etc.

[Mike #19861]

 I could not directly blame the rad shop for causing the problem, but may have accelerated the leakage in the gasket. Also, it is not recommended to pressure flush these engines.

 But, these engines were more known for intake manifold gasket failures that for head gasket failures. Remove the intake (which has to come off anyway to replace head gaskets) and carefully inspect the gaskets around the water passages. When they go, coolant is pushed into the intake valley and mixes with the oil.

 When you replace the gasket, make sure you use the updated GM gasket set, the one with the spring washer bolts, impacted graphite gaskets, tap and so on (P/N 3634742). Follow the torque procedures included with the set.

 If you go further, and replace the head gaskets, use ony good quality gaskets. GM or Victor-Reinze gaskets are a good choice. And remember DO NOT rotate the engine with the heads off. Then you will be in for a lot more work.

 Once done, and done properly, you can expect many more years of service form this engine. The 4.5 was a good engine.

  Mike