Weak valve pressure?

[talentfreak]

While we were adjusting the Valves we noticed that some of them you can actually push back down on them while they are fully raised? You should not be able to push back down on the valve should you? What would cause the weakness?

 

[dq409]

Old springs,,,,Over heated,,,,,, a dozen other things,,,
How many miles on the engine ???

 

[talentfreak]

I was told when I bought the motor that it only had 21,000 miles on a rebuild, but that doesn't mean that the springs were replaced does it?

 

[64ss409]

weak valve springs

I have seen a lot of low performance engines that you can push the valves down by hand. It does not necessarily mean they are "bad". They may be weak enough that you could have valve float in the higher rpm range, but they probably are fine for a daily, or weekend, driver. Kinda depends how you plan to drive it.

Check for broken springs. They make it easy to push the valves down and are sometimes hard to find, depending on where they cracked. Look em over good.

Ron