Is it necessary to relieve valve springs during storage


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By Vic Correnti - 13 Years Ago
I have fought with this over and over again. If a valve spring is designed within it's yield stress and below its annealing temperature limits then why relieve the pressure during the storage over the winter or long times that it is not run. I usually have my car out during the winter and go for a ride on dry winter days but this year I probably will not for a couple of months. I have even cranked over the motor at times of long storage, but is it necessary? I had my front coils out a few years back and checked the free travel and they were within limits, the car does not sag and these springs are over 50 years old.
By pegleg - 13 Years Ago
Vic, I don't, but probably the only way to really find out would be to relieve 1 head's worth and leave the others in place. Check them all at the end of Winter. I'm not gonna do it.
By gekko13 - 13 Years Ago
JMO but, it seems to me that another major factor besides temperature and range of motion in the loss of spring tension is the number of cycles it is subjected to.  An engine at rest is not putting on very many duty cycles on the valve springs. 
By DANIEL TINDER - 13 Years Ago
Springs under continuous tension are supposed to get progressively weaker, but I always leave the magazines in my auto pistols fully loaded, and they never jam. Likely they will someday (feed failure), but meanwhile I would rather have the extra rounds on tap.



Seems to me, turning a stored motor occasionally would not only distribute spring wear more evenly, but also reduce the inevitable wear on that specific point of the cam lobes. But, you would have to keep track (recorded log record) of where the timing mark ended up each time. Murphy's Law would dictate it will land back on that exact same spot when it quits cranking.
By Ted - 13 Years Ago

Lots of factors on whether to relieve tension on the valve train if the engine is going to sit for awhile.  A couple of those factors would include the valve spring brand or manufacturer and the lift at the valve.  It would be highly recommended to relieve the valve train tension on all out racing engines that sit dormant for periods of time and especially those with extreme lift camshafts.  For the rest of the performance orientated engines, some of the after market valve springs out there are simply not robust enough to stand being compressed for a period of time.  And while stating the obvious, the more the lift, the more stressed the spring is when the valve is simply sitting in a ‘full open’ position.  Stock valve lifts not so much a problem but performance and racing lifts do put exponential stresses on the springs.  The quality of the spring itself will dictate if these stresses are detrimental to the overall life of the spring or not.

 

Vic.  In your case, the Isky beehive springs for a .600” lift Y are very robust so if your engine is simply sitting for ten weeks or so, I wouldn’t worry too much.  You could go out there every 4-6 weeks or so and rotate the engine over a full turn which would help to cycle the springs but if it’s too cold to do that, I understand fully.