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Old 09-19-2016, 11:08 PM   #11
Mrturner1
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Join Date: Nov 2015
Location: Colfax California
Posts: 1,644
Re: Diagnosing a misfire

Quote:
Originally Posted by RichardJ View Post
>> I set the lash too tight, and if the lash is too tight then there's no buffer between the lifter and rocker arm and that's how you get a flat cam correct?<<

Buffer? What the hell do you think you're talking about?
If the valves are too tight, you run the risk of holding the valves off the seat or not letting the springs hold the valves tight against the seat for good heat transfer. That can lead to burnt valves.
If the valves are too loose, the valve train is noisy and really loose, hammering causing excessive wear.
The most important aspect of valve lash is to allow for heat expansion and not reach either of the extremes mentioned above. Hydraulic lifters self adjust to allow for expansion, never need readjusting and are much quieter.

Stop trying to use valve lash as a tuning aid.

The cam is not causing the rich mixture. The rings are not causing the rich mixture. A flat cam lobe is not causing a rich mixture.
You don't wipe out 16 cam lobes at the same time. If all the adjuster nuts are at approximately the same height, you don't have a cam problem. You did just adjust them. I have to assume you adjusted them correctly.

Stop flitting from one wild guess to the next.

Get rid of the vacuum advance. adjust idle down to 600 and see if the idle mixture screws are responsive to adjustments in or out from the 2 turns you set them at.
I'm making the assumption that your 2 turns out is a setting and not an actual adjustment. Use your vacuum gauge and a tach.

>>36 total all in at 3000 rpm.<<
Who cares. At this point it is more important to know at what rpm mech advance begins.

This guy got mad too. I must just sound like I'm not taking advice or something, although I assure you I'm listening to everything you guys say. I might not be correct when I take a shot at what may be wrong, but I am still learning. As far as I knew, the carb settings were all good to go. Mixture screws were exactly where member Hugger said to put them, idle speed was set wherever it needed to be after I set timing, and the rest of the carb stuff I don't know about yet.
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