It appears that I have a blown head gasket (overheating/bubbles in the
radiator) in my 235. I will verify with a compression test, but am pretty
sure that is what I'll find. Hope not, but I don't hold out too much hope.
Not sure why it showed up now (unless an engine that has sat for awhile is
more prone to this, as mine was sitting for almost 6 mos).
Anyway, I figure that before I pull the head to replace the blown head
gasket, that I might first try retorquing the head bolts. I NOW know that I
should have done that shortly after the initial rebuild, but I didn't
through ignorance. Now, after many thousands of miles, what is the correct
procedure to do this. The way I see it, I have two options before just
pulling the head and replacing the gasket - in the hope that the retorquing
will eliminate the leak - I have heard that it is a good idea to try this
before going for a new gasket.
Options: 1) Either simply retorque each bolt without first loosening it (of
course following the correct torquing sequence), or 2) first LOOSEN a bolt,
then retorque. My inclination is to do it the second route in case the bolt
had "sealed" itself in place, but possibly at an incorrect torque. But,
before doing anything, I thought I'd poll the group first and see if anyone
had had any prior experiences/successes. Only other consideration is
whether or not (if I go the second route) to first loosen ALL the bolts
before retorquing, or whether to loosen one bolt, then retorque before
moving on to the next. I know these heads are prone to cracking, so want to
go the route least likely to result in that happening (unless it already has
and that that is the cause of the failure versus the head gasket). I got my
gasket set from Patricks and if I remember correctly, the gasket was a
copper gasket, but not real sure at this point.
When I was initially rebuilding the engine five years ago, I almost torqued
off one of the bolts as I was tightening it. Fortunately, I had a funny
feeling that something was not right as I approached the final torque and
backed the bolt out. The head of the bolt was about 3/4 of the way torqued
off. Got a spare bolt from a friend and completed the job, but now, I am
also wondering if I should replace all the bolts before attempting any
retorque. If others feel this is the more "prudent" approach, does anyone
know what would be my best (and/or cheapest) source for head bolts for a
235.
Thanks,
Rob
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