Re: Super M

Posted by Jason Simmerman on April 14, 2007 at 21:56:24 from (71.168.38.251):

In Reply to: Super M posted by Jeff McBride on April 14, 2007 at 20:10:40:

Well, if it were the governor it would just lose power not pop and miss so I wouldn't suspect that "at least right off the bat"... Might be a cracked or not so well sealed gasket on the manifold, but not likely. With that miss and it missing slightly at idle and if it idles down nice I suspect you have one of two things are going on here. You have a sealing problem with one of your cylinders, or you have a cracked head. Under load a small miss will get worse because cylinder pressures go up IE getting hard into the governor and governor is adding more fuel and air. I'd get a compression gauge if you don't already have one and run the motor for about 10-15 minutes and run it around alittle and shut her down. Ensuring you have a good strong battery and hooking a charger to it pull all 4 sparkies out of it and screw your compression gauge into the sparkie holes. Crank her over 3 or 4 times and see what you got. My dad's M with a Super M sleeve and a domed piston kit which was redone 30 years ago has almost the same problem. I found that he has a valve leaking on the number 2 cylinder. Motor makes darn good compression particularly considering it's age between rebuilds (about 120 psi on cylinders 1,3, and 4 but cylinder 2 is only about 100). You should only have 10% of deviation from highest to lowest in your compression numbers. If you find you have one cylinder that is much lower than another squirt some motor oil in the cylinder and retest. If the pressure goes up by a noteable margin you have a ring sealing issue, if it stays the same it's most likely a cylinder head issue. Now, being it's a new rebuild maybe the rings aren't fully seated yet but in any event. Could be a weak valve spring also. I'm assuming you replaced all the components in the heads, but sometimes there are machining errors that occur. I'd do a compression check and go from there. It seems like you've covered everything else. Now make sure the motor is indeed sound.

Replies:

• Re: Super M Jason Simmerman 22:21:48 04/14/07 (0)

Add a Reply 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 ]