(800) 853-2651
SHOP NOW

Tim Powell here again; Farmall A timing problem

T

Tim Powell

New User
Ok; I took your advice and thanks. I spent a couple hours jury rigging a caliper that would measure the clutch housing ring gear diameter. Then I measured the degrees off before TDC the mag tripped and laid that out along the circumference and got 14 degrees. The 8 was bad guess. I've been through the timing sequence 30 times by now and not sure of anything anymore. I would have already started tearing the front end off but I had to go to a local Ag fair this PM.
 
Are you saying you can't retard the mag enough to get the impulse to trip at the correct timing, TDC???

In other words, the governor/mag drive is too far advanced?
 
Yes; The impulse coupling trips 14 degrees before TDC. That means the magneto can't rotate far enough towards the block for the coupling to trip on time. I can almost get her started but she will backfire. I'm trying to avaid that if possible.
I just completed a carb rebuild and haven't been able to make any fine tuning to it yet because she wont start.
This whole rebuild is in the third year now and I'm so close.
 
Bummer. I hope the cam timing is correct. Assuming it is, you will have to remove the governor to fix it but the rest won't be bad.

Turn the engine to #1 TDC. The mag will have just tripped.
Take the distributor cap off and note the postion of the rotor then remove the mag.
Pull the governor housing off. You will run into interference from the fan shroud so will need to remove it or loosen and tilt the radiator or whatever it takes to get clearance.
Pull, rotate and reinstall the governor assembly. You can look for the marks. They should be visible at this position. If not, turn it 2 teeth and reinstall. You need to turn it to the left. There are 33 teeth, so each tooth is 11 degrees.

Reverse the steps to reassemble. Except I would install the mag and try to time it as soon as the governor housing is in place. That minimizes the rework if you find it needs one more tooth. Finish reassembling after it is timed. When installing the governor, make sure the rotor is pointing the same way it was when you removed it. If needed, rotate the magneto backwards until the rotor is in the right place.
 
Yes his gear timing is off and i told him how to check it and here we are days later and he is still asking questions so what else is his problem.
 
Is it running? If so put a timing light on it to find where it firing. If its firing at about 30 degrees BTDC then the mag is positioned right. If thats the case then I would still go for a mag adjustment prob before tearing the front off the tractor. Right now I have similar prob on an H and I know thats all lined up right because I've just rebuilt the engine (Incidently to 'prove' it I put the mag on my running M and got the same problem).I'll let you know sometime next week.Good luck. MTF
 
Hi I've just realised that what I said in my last may not hold good for you because I have Lucas mags with index plate adjustement on the impulse coupling and you may not be able to carry out the same adjustment. So may I suggest that you speak to a kindly nieghbour and try your mag on his tractor or his mag on yours whatever. that will finally tell you where the prob is. Sorry MTF
 
You are going to have to pull the gov housing and check if the dot is lined yp with the dot on the cam gear. Some run them a tooth off for more advance for pulling so i am told but the dot on the mag gear and the dot on the cam should be lined up. I have had a bunch in the last few yrs that i have overhauled and they better be lined up if ya want them to start. Then check the rotor to see it is lined up with the tower when it fires. You can get the gov off without removing any thing else just be patient cause it can be done. It will help if the fanbelt is loosened up.
 
You must log in or register to reply here.

Similar threads

W
Timing a H4 Magneto
Replies
6
Views
786
teddy52food
T
K
Super M total timing?
Replies
9
Views
1K
the tractor vet
T
9
Ford 800 timing problem?
Replies
9
Views
3K
JMOR
J
J
Unstyled A Timing
Replies
10
Views
3K
John T
J
A
Farmall A timing
Replies
6
Views
2K
Anonymous-0
A
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.

Copyright © 1997-2024 Yesterday's Tractor Co.

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters
Website Accessibility Policy

Back
Top