Re: warm rap

Posted by Bob M on September 08, 2004 at 09:02:45 from (165.170.128.65):

In Reply to: warm rap posted by jeffrey on September 08, 2004 at 08:10:47:

What's oil pressure like? If it falls to close to 0 as it warms up and the rap builds it's probably a worn rod bearing.

However if oil pressure stays in the normal range it could be piston slap, a worn piston pin bushing or possibly a loose/broken camshaft drive gear hub.

Try pulling the plug wires off one at a time with the engine running. If the rap changes it's a piston or bearing problem on the non-firing cylinder. If the rap doesn't change then it could be the camshaft gear.

I've seen cam gear failures on several Farmalls with live hydraulic pumps. It's caused by the added load of the pump on the gear. However if the cam nut was improperly installed on a tractor without live hydraulics, the nut could still work loose. That'll let the gear flop around inside the timing cover and cause the rapping exactly as you describe.

Quick way to determine if it's the cam gear is to pull the distributor drive (mark the rotor location first!) and peek inside. If you can move the gear at all with your fingers you've found the problem.

Good luck!

Follow Ups:

Post a Followup Name: E-Mail: Subject: 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 ]