Hi,
you know I've always wondered about taking the pressure off the valve
springs.
I have some drag race friends with dragsters and they swear you have to back
off the valves when the motor sits for long-the say the springs will take a
set if compressed for long -I say hog wash.
Jon
-----Original Message-----
From: Joseph Sholtes <joeiv@concentric.net>
To: John Cowan <jfcowan@earthlink.net>
Cc: triumphs@autox.team.net <triumphs@autox.team.net>
Date: Monday, February 16, 1998 9:55 AM
Subject: Engine Storage Question, Valve Springs & Metal Fatigue
>> >Joe IV wrote;
>
>> Carl,(Musson)
>
>> > ~snip~
>> >
>> > If you are likely to store the engine longer, it would be wise to
remove
>> >the rocker shaft, to aleviate stresses on the valve return springs.
>
> ~snip~
>
>> > It's a good thing. (Stolen quote, there)
>>
>> > JOE IV
>
> John Cowan replied:
>
>> Joe,
>> My TR-3A sat for 28 years. What would the symptom be regarding the
valve
>> return springs that sat under tension for so long?
>> Thanks.
>> John Cowan
>>
>
>John,
>
> Good question. Maybe my advice is worrying over nothing (GL-4
>vrs GL-5, and unleaded fuel come into mind). But I feel that a fully
>compressed valve spring, sitting for years, has got to be weaker than
>one that has remained relaxed. Well, realatively relaxed, I mean, there is
>still some compression from the retainer.
> As for problems, I guess a spring that's compressed so long would have
>less elasticity. Granted, I'm not a metalurgist- so my advice may be
wrong.
>But I would venture to say that a weakened spring would lead to valve
"float"
>at a lower engine speed. I don't think that the metal would be fatigued to
the
>point of failure, but I wouldn't be surprised if that were the case.
> An immediate, though unlikely, symptom might be that the valve spring
would
>be so compressed for so long that when it was relased, it would be so short
>that the keepers/retainer may fall off, and the valve may drop. Doomsday
pre-
>dictions, I know- but who knows?
> With any engine that has sat so long it should be oiled in the cylinders
and rotated
>over slowly by hand a few times before any attempted start, anyway.
> Leaving now, before
I bum everyone out,
> JOE IV
> TR 250
> WALLINGFORD, CT. USA
>
>
>
>
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