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Title: Valve settings Post by: pearo on February 24, 2007, 05:31:42 AM My grey motor valves are a little noisy and I was wondering if anyone can tell me what clearance I should set them cold. My book says to set them running at 12 thou and 8 thou but I'm a bit reluctant to do them on the run so if someone has the settings for a cold or warm set could you please let me know.
Cheers Rob Title: Re: Valve settings Post by: mcl1959 on February 25, 2007, 09:59:10 AM I find them hard to set on the run so I warm the engine up to running temp, then measure the clearance while the engine is running, then shut the engine down and adjust as necessary. Restart the engine and measure again. Keep doing this until the running specs are right for all valves.
Important that clearance specs are done whilst engine is running. Ken Title: Re: Valve settings Post by: FB_MAD on February 27, 2007, 12:05:58 AM You can also find in a well used engine that the section of the rocker arm that contacts the valve stem will wear a groove due to the rocking/rubbing action of the rocker arm on the tip of the valve stem (this is one reason roller rockers are good if you can get them......none available for greys unfortunately).
We are only talking a few thou wear amount here I know but it can make a difference as even though you have set the clearance to spec it may still have more clearance than it indicates. Years ago I had this problem with a grey where no matter how much I tried to get the valve clearance adjusted to spec the motor was still noisy. Pulled the rocker assembly off and found wear on the arm as described above. Had the rocker arms refaced, then reassembled the rocker assembly, set clearances to spec and the motor was very much quieter. To do it properly I should have refaced the valves as well but couldn't be bothered removing the head at the time. If you have rocker arm to valve stem wear you could set clearance a thou or two smaller and see how it goes but make sure its on a hot engine. I've set clearance a few thou smaller than spec on a few well used motors this way and never encountered any problems. Terry. Title: Re: Valve settings Post by: pearo on February 28, 2007, 03:17:25 AM Thanks for the info fellas, I will have a look at the rocker gear as you say Terry, and set the valves as Ken suggested.
Cheers Rob |