Skip thanks for starting the thread. I'm a newbee to the SC world and appreciate all the help and expertice on this one. Oh, and I'm located near the Quad Cities area in Illinois (not sure where Arizona came from, but it might be a good place to go when Im ready to retire..)
The root cause was overheating from bad connection
on the cooling fan. I was not driving the car when it happened, so don't know how hot it got. My son was driving the car when the cooling fan connection failed, so he got to fix the cooling fan connection. Only Dad gets to fix the fun stuff like HGs.
Sadly, after fixing the cooling fan we had fluctuating engine temp gauge and steady bubbles in the coolant reservoir
which are classic HG failure symptoms caused from compression leak into the coolant system. We "burped" the air out of the system probably 20 times over the next few days in hopes it was just trapped air, but turns out to be HG
(or possible cracked head.. hope not).
Planning to do more diagnostic tests and try to determine which cylinder(s) is leaking. Will start with a coolant system pressure test. Might do a compression test too if needed to determine which cylinder is leaking. The leak is small compared to other non-SC engine HG leaks I've had, so I'm wanting to have a good idea where to look when inspecting the failed gasket. Since I don't know how hot the heads got, I'm planned to have the heads pressure tested to test for cracks while they are off. Hope they're not cracked, but better pressure test to be sure.
Regarding the O-rings, it appears there is an option to re-use them depending on condition of the o-rings and head surface. I would have thought the o-rings were made from a more malleable material that would "squish" when the heads were torqued down. Stainless is pretty hard stuff so probably is safe to re-use.
Any futher thoughts on re-using???
One more concern... if we were to not re-use the o-rings and machine the grooves out, the big blue book states "do not plane or grind more than 0.010" from the original head surface". Sounds rather conservative to me but a lot less than the .035-.040 required to remove the o-ring grooves.
Sounds much safer to either re-use the o-rings or get the grooves TIG welded and the heads re-surfaced??
I'll give another update after more testing and the engine is dis-assembled. Till then, I'll keep checking back for any further comments and advise.
Thanks to all.....