OHV Cam Drive
OHV Cam Drive
(OP)
Some resources said that the OHV engine can only have timing chain or gear and not belt. Is this true? If yes, can anybody give me a reason? Thanks!
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS Come Join Us!Are you an
Engineering professional? Join Eng-Tips Forums!
*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail. Posting GuidelinesJobs |
|
RE: OHV Cam Drive
Regards
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
RE: OHV Cam Drive
In a non-interferance engine (The pistons will not contact open valves) there is no problem.
In an interferance engine, damage will be done if the piston contacts an open valve. For this reason, a manufacturer may choose to go with a chain or gear drive for greater reliability.
P.s. The old pinto went over 200,000 miles. The belt lost it's teeth once when running, but no damage was done. I replaced the belt and drove the car for more years.
RE: OHV Cam Drive
Bob
RE: OHV Cam Drive
RE: OHV Cam Drive
Blacksmith
RE: OHV Cam Drive
RE: OHV Cam Drive
http://i
RE: OHV Cam Drive
Franz
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
RE: OHV Cam Drive
RE: OHV Cam Drive
Chains love oil. The folk designing chain guides have gotten really good at it of late and have helped to make chains the preferred automotive drive for OHCs. Find out all you can about guide design before you begin laying out the chain route.
The connecting rod approach (4.5 liter Bentley and others) required a 2:1 gear. As with shaft driven OHCs, temperature compensation was a problem. Shafts with bevel gears usually have some kind of axial adjustment for the gear position at the head.
Okay, a pop quiz: The Crosley OHC engine had a shaft drive with right angle bevel gear assemblies at the crank and the cam. The shaft between the engine and the cam spun at 2/3rds engine speed. What was the gear ratio of the bevel set drivng the cam?
RE: OHV Cam Drive
RE: OHV Cam Drive
RE: OHV Cam Drive
http://www.wilcoxengines.demon.co.uk/enggall.htm
RE: OHV Cam Drive
I remember vaguely seeing a system such as you mentioned.
I think it was a Honda motorcycle. somewhere there was a 2:1 gear reduction I think on the bottom end. I do remember the drive because it was so unique. Each shaft had three eccentrics about 1 1/2 inch in diameter. They were ofset 120 degrees. The connecting rods were flat metal about 3/16 inch thick. When it went together, one set of eccentrics were fixed to the shafts, and the flat plate con-rod placed on them. Then the second set was put in place, displaced 120 degrees. Then the last set. As I remember, the con-rod plates were in contact with each other and a lot of lubrication was involved.
I seem to remember my friend spending a lot of time in the shop with his nearly new bike and I saw the cam drive arrangement quite a few times.
yours