Dean Mericas writes:
> I have been monitoring the compression in my TR4 over the past two years,
> and am starting to get concerned. During my end-of-season, before we pack
> it away, just to make sure I have all my winter projects identified, going
> over the car ritual, I measured compression. With the engine up to
> temperature (170 F) and all plugs removed, I observed the following:
> #1 100 #/in2
> #2 170 #/in2
> #3 155 #/in2
> #4 155 #/in2
> All of the plugs had a nice tan/grey color, and there was no evidence of
> fouling or oil splash.
> Clearly I have a problem, hopefully just in the #1. I squirted some 20W
> oil in the #1 cylinder, turned the engine over a few times and took
> another reading -- came out the same.
> 1. Are there any other tests that I should do before tearing into
> the engine?
Well, let's see. You have bad compression in one, and only one, cylinder.
My first suspicisions would be either valve adjustment, or a leaking head
gasket. Minor ring-related problems will usually give a better reading after
a few squirts of engine oil. Thus, I would suspect either valve adjustment,
a leaking head gasket, or a more major problem. Since the valve adjustment
can be checked with only removing the rocker cover (and not the whole head),
I would *definitely* check that first.
If that were to result in no improvement, pulling the head would seem like
the next step...
--ken ('74 TR6)
Kenneth B. Streeter | ARPA: streeter@sanders.com
Lockheed Sanders, PTP2-A001 | UUCP: ...!uunet!sanders.com!streeter
65 River Road | Voice: (603) 885-9604
Hudson, NH 03051 | Fax: (603) 885-0631
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