Welcome! Please use the navigational links to explore our website.
PartsASAP LogoCompany Logo (800) 853-2651

Shop Now

   Allis Chalmers Case Farmall IH Ford 8N,9N,2N Ford
   Ferguson John Deere Massey Ferguson Minn. Moline Oliver

Attention Forum Users: On the 28th of December 2023 at 9:00am Central Time, we will be taking the forums down for maintenance while we prepare the new forums for your use. Please click here for more information.

Discussion Forum
:

37 B timing off

Welcome Guest, Log in or Register
Author 
David

07-16-2003 18:16:51




Report to Moderator

Have a nice 37B with rebuilt engine, carb and new magneto. Have trouble starting it and it backfires when I spin the fylwheel. Makes me think I need to rotate the magneto some, but which way and how do I know when its right? Your help is appreciated - thank you.




[Log in to Reply]   [No Email]
Clooney

07-17-2003 07:12:20




Report to Moderator
 Re: 37 B timing off in reply to David, 07-16-2003 18:16:51  
David, seeing as you say you �have trouble starting it� & not that it won't start, I will assume the plug wires are on correctly.
~That backfiring while turning the flywheel could be anything from an ignition problem , to a carb problem to, a valve problem, to ?. ~You are beginning at the correct place by getting the ignition system checked out first.
~Start with the spark plugs & [REPLACE THEM], bad or partially fouled sparks plugs are a big problem on the old hand start Deere's. ~Once the plugs are replaced, verify the spark plug wires are in good condition & of the solid metal core type & not the automotive TVRS resistor type [carbon resistor wires on a mag system is a sure way to have starting problems]
~Once you are sure you have good plugs & wires you can move on to the timing,,, first verify that the mag impulse gives a good solid audible snap every time the flywheel is turned a complete revolution. If the impulse checks out ok then you can check the ignition timing. To check the starting lag angle [starting timing] just rotate the flywheel in the stating direction & listen for the mag to snap. If the starting timing is correct the mag will snap as the L/H impulse writing on the flywheel is even with the case mark [the case mark is at 3 o�clock directly behind the flywheel & even in height with the center of the crankshaft. That is on a Wico mag C or X mag. If you have a gear reduction mag the mag should snap every other time the L/H impulse mark lines up with the case mark.
~If the timing is incorrect [yours might be] just loosen the mag retaining bolts & rotate the top of the mag forward to retard the timing & to the rear to advance the timing. ~If you can�t rotate the mag far enough to get it to snap at the correct time just post back & give us the mag make & model, you could have a mag problem or a governor to mag timing problem.
~Let us know how it works out?

[Log in to Reply]  [No Email]
John T

07-17-2003 06:12:48




Report to Moderator
 Re: 37 B timing off in reply to David, 07-16-2003 18:16:51  
Hi Dave, the good G Man has you covered pretty well, and the backfiring sounds like the mag may be in 180 out depending upon what kind it is. If its a Wico C or X or similar type (turns at crankshaft speed and fires TDC on BOTH power and exhaust) a simpe plug wire reversal may make her run. Or, you can leave the wires where they are and remove the mag and rotate the flywheel 180 and reinstall it and see what happens (again, depends on what mag you have). Similar to the good G Mans advice, when the left cylinder is at TDC on its compression power stroke, the Left Hand Impulse timing mark on the flywheel should be at the 3 o clock position in line with the flat mark on the tractors side, and when the flywheel is rotated past and just at that mark, the mag should snap to fire the top terminals plug wire leading to the left cylinder. To change that, loosen and rotate the mag CCW to advance and CW to retard the initial start timing. If she fires too soon before TDC the flywheel may kick back and I set mine to snap just as the LH Impulse mark passes by the 3 o clock flat mark. Still not knowign what mag you have, a simpe plug wire reversal may cure the problem if its the right type mag suitable for such. This assumes the crank to cam and cam to governor shaft are all in time. If the governor shaft is out of time, this may not all be accurate and post back for more info. If it is in time at the TDC location described above, the female drive cog slot in the governor shaft end that drives the mag should be flat horizintal fore and aft. If its one of the Faribanls Morse type gear reduced mags, if its in 180 out of time, it needs to be installed correct.

Good Luck John T Nordhoff

[Log in to Reply]  [No Email]
Gman

07-16-2003 20:32:31




Report to Moderator
 Re: 37 B timing off in reply to David, 07-16-2003 18:16:51  
David I have a 38 B and I had problems getting it lined out(had a serious brain F***)one of the guys on the board helped me so I'll try to help you. Take #1 spark plug(next to flywheel)out turn flywheel till it whooshes and blows your finger off the plug hole,at this time the LEFT HAND IMPULSE should be @3:00 aligning with mark on case(if not you will need to look at flywheel position),ok observe the position of drive lug in govenor (Mag. removed)the lug should be in the horizontal position(if not you will have to raise gov. housing enough to move a tooth or so to get proper lug position)once you've done this install mag. align lugs and position to of mag at the 2:00 position,then rotate mag.counterclockwise till it fires then tighten bolts. This looks complicated and lenghty but it really is simple. I'm one of those guys that does something and reads the instructions later to see where I fouled up,th John Deere IT manuel has some aweful good instructions,I found them after Clooney told me how to time the engine,later Gman

[Log in to Reply]  [No Email]
[Options]  [Printer Friendly]  [Posting Help]  [Return to Forum]   [Log in to Reply]

Hop to:


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 ]

Home  |  Forums


Copyright © 1997-2023 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