Re: 47A ignition timing-

Posted by Steve - IN on September 26, 2002 at 15:26:31 from (12.222.132.139):

In Reply to: 47A ignition timing- posted by Jim on September 26, 2002 at 13:48:21:

Jim,

Don't ignore the rest of it -- that is, take it out and see if it pings. The ping is preignition and it causes nasty pits in piston tops and valves. Never seen one actually melt, the pits are bad enough, but can be avoided by backing down the timing.

The whole idea is that an older engine doesn't seal as well as a new one. Therefore the mixture in the chamber doesn't burn as rapidly and takes longer to achieve the same force it would if it were under higher pressure - so you can trigger the spark a little sooner. If your engine is making more speed with more advance - while mixture and everything else stays the same -- that should tell you it's more efficient at more advance -- it's using the explosions in a better way and turning faster because of it. Just remember that you're only turning a flywheel when you're sitting there, and the story changes when you're under load. The other thing to watch for is that you're not running too hot with more advance, which you can tell from reading the plugs.

I'm guessing you're not trying to extract maximum performance from your A, and are probably more interested in preserving it. So be careful. The other post was about a guy who had rebuilt an engine with higher compression ratios and therefore more compression than stock -- and was needing to back off timing because of it.

As a P.S. -- my popper only has a couple of timing marks. Is 58 something you're reading, or guesstimating?

Steve

Follow Ups:

• Re: Re: 47A ignition timing- Jim 09:33:43 09/27/02 (1)
  • Re: Re: Re: 47A ignition timing- Steve - IN 17:00:57 09/27/02 (0)

Post A Followup Name: E-Mail: Subject: Re: Re: 47A ignition timing- Comments: Optional Link URL: Link Title: Optional Image URL: Email Notification: If you check this box, email will be sent to you whenever someone replies to this message. Your email address must be entered above to receive notification. This notification will be cancelled automatically after 2 weeks.

TRACTOR PARTS	TRACTOR MANUALS

We sell tractor parts!  We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]