Home 
enjoy watching Utube video's of our trucks and engines, and rebuilds. Some new ones on rebuilding and "tuning" our side valve engines, sometimes cars or trucks. Just watched a video of the valves/springs at idle. The tappets rotated at a rate perhaps one complete rotation maybe in every 10 sec. Some watchers suggested worn cam lobes would do this, but I think I recall that tappets are finished with a slightly round surface, and are supposed to rotate.
Any thoughts.....
All the best, and stay safe. NV
Valves/tappets rotate in operation?
Moderators: Cal_Gary, T. Highway, Monkey Man, robi
Re: Valves/tappets rotate in operation?
just answered my own query. NV
In an internal combustion engine, a tappet (also called a 'valve lifter' or 'cam follower')[3][4][5] is the component which converts the rotation of the camshaft into vertical motion which opens and closes the intake or exhaust valve. The types of valve lifters (i.e. tappets) commonly used by automotive engines are solid lifters, hydraulic lifters and roller lifters.[6][7]
An alternative to the tappet is the 'finger follower', which is a pivoting beam that is used to convert the camshaft rotation into opening and closing of a valve. Finger followers are used in some high-performance dual overhead camshaft engines (instead of bucket tappets), most commonly in motorcycles and sports cars.[8]
To reduce wear from the rotating camshaft, the tappets were usually circular and allowed, or even encouraged, to rotate. This avoided grooves developing from the same point of the tappet always running on the same point of the camshaft. However, in some relatively small engines with many cylinders (such as the Daimler '250' V8 engine), the tappets were small and non-rotating.
Most 'flat' tappets (i.e. without rollers) usually contain a slight radius which creates a subtle mushroom-shaped surface, since a perfectly flat surface leads to 'slamming' against a steep camshaft face.
Adjusting the tappets
In an internal combustion engine, a tappet (also called a 'valve lifter' or 'cam follower')[3][4][5] is the component which converts the rotation of the camshaft into vertical motion which opens and closes the intake or exhaust valve. The types of valve lifters (i.e. tappets) commonly used by automotive engines are solid lifters, hydraulic lifters and roller lifters.[6][7]
An alternative to the tappet is the 'finger follower', which is a pivoting beam that is used to convert the camshaft rotation into opening and closing of a valve. Finger followers are used in some high-performance dual overhead camshaft engines (instead of bucket tappets), most commonly in motorcycles and sports cars.[8]
To reduce wear from the rotating camshaft, the tappets were usually circular and allowed, or even encouraged, to rotate. This avoided grooves developing from the same point of the tappet always running on the same point of the camshaft. However, in some relatively small engines with many cylinders (such as the Daimler '250' V8 engine), the tappets were small and non-rotating.
Most 'flat' tappets (i.e. without rollers) usually contain a slight radius which creates a subtle mushroom-shaped surface, since a perfectly flat surface leads to 'slamming' against a steep camshaft face.
Adjusting the tappets
Re: Valves/tappets rotate in operation?
just put plugs back in and the engine promptly fired up and idles smooth as silk, No clicking tappets, and when I get the new valve cover gaskets, will be done. Am ordering the Essential Lube recommended by Charles T. But have to buy a case of 12 oz bottles. Cheaper than a bent valve, for sure. NV
Re: Valves/tappets rotate in operation?
Nice! I was going to share that mine were spinning when I adjusted my valves a few years back.
Gary
Gary
Cal_Gary
1954 M37 W/W
MVPA Correspondent #28500
1954 M37 W/W
MVPA Correspondent #28500
Re: Valves/tappets rotate in operation?
if they don't spin its time to worry! also on some HD engines usually in trucks and boats and stationary power plants they have bearing plates under the exhaust valves and they spin too
Those old 50s mercedes engines did not last very long. I used to work with a German guy on vintage Mercedes in Seattle. He would come help me work on the mechanical fuel injection systems they ran in the old days. some of the procedures take 2 people. He worked in the factory in Germany in the 50s and 60s. He said a lot of those 50s engines only lasted 35K miles. the 60s things got much better for them but still some smaller engines had issues
Those old 50s mercedes engines did not last very long. I used to work with a German guy on vintage Mercedes in Seattle. He would come help me work on the mechanical fuel injection systems they ran in the old days. some of the procedures take 2 people. He worked in the factory in Germany in the 50s and 60s. He said a lot of those 50s engines only lasted 35K miles. the 60s things got much better for them but still some smaller engines had issues