Valve seals
#1
Valve seals
Acquired this motor with my current project. Has trws it appears so work has been done. Story is it burns oil. All the valve seals are at the top of the spring like the picture, I would assume the problem is located. Machine for the press on valve seals that go over the guide?
#4
Looks like those may be the "short" factory type seal which are used on the exhaust valve. The intake valves use a slightly longer seal of the same type. They are designed to be placed low as possible on the valve stem when assembling the heads and upon start up find their place on the valve stem. When the valve is opening the seal covers the upper valve guide area and prevents excessive amounts of oil from going to the valve guide. Some builders will put the "short" seal on both intake and exhaust. This will allow more oil to the valve guide (due to the vacuum effect when the intake valve is opening) and result in "abnormal" oil usage. Since there is no vacuum effect on the exhaust valve opening the shorter seal works fine there to prevent excessive puddling at the top of the valve guide. If you use positive type seals on the stock iron factory valve guide you will prevent the small amount of oil from lubricating the valve guide and accelerate guide wear. Positive seals may be used with replacement bronze valve guides which don't require as much lubrication as the iron guides.
Thread
Thread Starter
Forum
Replies
Last Post
Almond900
Parts For Sale
1
November 1st, 2016 09:29 PM