(800) 853-2651
SHOP NOW

F20 timing.

A

Andrew Psencik

Member
Had the f20 running ok at best. Finally looked at the rockers, and found that multiple valves were very far out of lash. Some had over half an inch. So I adjusted the valves to .018 cold. Now the tractor runs like crap all over again. It"s popping and shooting flames from exhaust if I advance the throttle too fast. When under a load and the governor kicks in, it does the same thing. So now I"m thinking that by adjusting the valves so much, it now is out of time again. My question is which way should I turn the magneto to advance or retard. Do the problems I describe sound like its too advanced or too retarded? I usually remove the two bolts in the mag drive and rotate the mag to time. Thanks.
 
tha valves cant be adjusted correctly if its popping and shooting flames. each cyl. has to be on tdc of compession stroke to adjust valves for that cyl.
when you turn mag in same direction it rotates thats retarting the timing. opposite of rotation is to advance.
just use a straw in spark plug hole and when pulling up on crank the instant the mag trips you can see if your after top dead centre , as which it appears. if you have timing marks to go by then use them.
 
I use the flywheel D/C markings.Hopefully you can read them. Mag should trip just as D/c is going past the window (book says no farther than 8 degrees past window. Also, the crank pin on the pulley will be dead on horizontal. You can tell how close you're getting to D/C by watching the pin.
I adjust valves one cylinder at a time 1-3-4-2. Up to .020 cold is fine. If mag is in correct position and tripping at the right time, should fire right up.
 
sounds like you could have a carb problem too. Setting valves won't change your spark timing. Make sure your mag trips just after top dead center and then leave it alone. If you still have the problem, check valve lash and make sure none of them are sticking. If that doesn't eliminate it, make sure you have good plug wires and plugs and the cap is dry and not cracked. These old girls usually run really rich at idle, and if you lean the carb out to make it idle nice and smooth you will create the problem you describe, because every time you give it throttle or the governor does it is too lean and will cause a misfire. 3 1/2 turns out on the main jet is full rich and if you are much less than 2 you are probably too lean.
 
Andrew, When you set the valves to .018 Did you get #1TDC #2TDC #3TDC #4TDC when you set the valves? Carb running lean will make if back fire
run rough and so on. What have you set? and is it correct? You need to stop chasing things around. Get the timming right and valves right and clean the carb again. Do you have a manual? oldiron29
 
I have rebuilt the carb 4 times. The adjustment screws are missing plating. But that's it. I am sure it's clean. I'm not sure what's happening.
 
The oil priming cups on the valve cover are intact and closed. There are 2 other holes on the water manifold side of the valve cover that are missing and I do not know what they are there for so I have them plugged.
 
(quoted from post at 17:07:58 03/26/13) The oil priming cups on the valve cover are intact and closed. There are 2 other holes on the water manifold side of the valve cover that are missing and I do not know what they are there for so I have them plugged.
Click to expand...


i meant the fuel priming cups. pull your valve cover off and make sure the hollow tubes are plugged off. if not it'll act lean and not run worth a crap

i know, i did this once
 
Thanks a million. Right now I am student teaching and can not
spare the extra money for a manual for this tractor. But as
soon as I can I will get one. I did not know these tractors had
fuel priming cups. I'll check that tomorrow. I'm sure that's what
it is.
 
My thoughts too. Better recheck the valves. I tap them with a light hammer to see if they are sticking. After you tap a few you will soon see what I mean. The unstuck ones will snap back nicely bing bing bing
 
You must log in or register to reply here.

Similar threads

K
Kevin's gibson model a project
Replies
3
Views
300
Kevinwterry
K
D
268 injection timing help...
Replies
5
Views
208
damn1981
D
W
Farmall A hard starting - fueling issue
Replies
14
Views
664
C.Amick
C
pcdreams2
ford 3000 timing
Replies
18
Views
650
pcdreams2
pcdreams2
A
  • Discussion
1936 Farmall F20 Cane
Replies
0
Views
96
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