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

Shop Now

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

Farmall & IHC Tractors Discussion Forum
:

M burning points

Welcome Guest, Log in or Register
Author 
Wicksfield

05-31-2006 05:23:28




Report to Moderator

I recently converted my M over to 12V negative ground alternator. Using the ignition resistor provided with the kit, my input voltage to the resistor is about 14V and output is about 8V. I changed coils from the original 6V over to a 12V coil after I burned the first set of points thinking that could be the problem. Total, I've burned 3 sets of points with this set-up. 2 sets from TSC, 1 set from NAPA. Changed the condenser with each point set change.

What in the H is the problem!!??

[Log in to Reply]   [No Email]
Hermit

05-31-2006 18:00:36




Report to Moderator
 Re: M burning points in reply to Wicksfield, 05-31-2006 05:23:28  
Here's a couple of thoughts. You said the output voltage from the resistor was 8 volts. Did you check it at the coil? Maybe a wire crossed putting a full 14 volts to the coil. Is your points freely moving on their pivot point? If they are slow to close because of a tight fit, there could be high induced voltage at the points. Is the points spring properly connected to the insulator block on the side of the distributor? If the points spring tension is incorrect, that could cause points bouncing and burning. Food for thought. Have fun.

[Log in to Reply]  [No Email]
billde

05-31-2006 09:13:41




Report to Moderator
 Re: M burning points in reply to Wicksfield, 05-31-2006 05:23:28  
Is the neg side of the coil connected to the distributor? If not, polarity could be part of your problem.



[Log in to Reply]  [No Email]
Wicksfield

05-31-2006 10:01:33




Report to Moderator
 Re: M burning points in reply to billde, 05-31-2006 09:13:41  
Bill, negative side of coil is connected to distributor.



[Log in to Reply]  [No Email]
Allan In NE

05-31-2006 07:26:22




Report to Moderator
 Re: M burning points in reply to Wicksfield, 05-31-2006 05:23:28  
Wick,

Define "burning points". Are they actually burning the points clear away or are they just dis-coloring and pitting a bit?

A certain amount of "burning" is plumb normal. With 8 volts at the points, I just don't see the problem.

12 volt automotive applications with points always would run in at around 10.8 volts at the distributor side of the coil and they would easily run a year or 10,000 miles before they needed replaced.

Allan

[Log in to Reply]  [No Email]
Wicksfield

05-31-2006 08:05:56




Report to Moderator
 Re: M burning points in reply to Allan In NE, 05-31-2006 07:26:22  
The tractor ran so poorly the first time this happened, I thought for sure it was a fuel problem. I've never had a points problem like this before, so naturally I checked out everything and finally changed out the points.....couldn't believe that was the problem. Now, I get about 6 hours on a set of points. The points become back and pitted.



[Log in to Reply]  [No Email]
John T

05-31-2006 09:31:01




Report to Moderator
 Re: M burning points in reply to Wicksfield, 05-31-2006 08:05:56  
Wick, if the points are deeply pitted on one side thats indicitave of a bad or weak but more often AN IMPROPER SIZE CONDENSOR to match up with your coil. I fear your coil isnt matched up as far as ohms (need around 3 ohms) and inductance with whatever condensor microfarads you have. The mis match where the condensor isnt the correct size to match the coils inductance and resistance causes premature point burn up. You need to get a regular IHC 12 volt (NOT for use with external ballast i.e. NO ballst required) coil and a condensor to match and that should solve the problem.

I think that generic coil you claim is for use WITH OR WITHOUT a Ballast just isnt matching up with your condensor rating which is causing the points to burn up prematurely OR ELSE ITS SIMPLY WAY TOOOOO O LOW OHMSSSSS (should be near 3 ohms). For use "with or without" a ballast doesnt make good engineering sense to me for an old fashioned tractor points n condensor coil ignition system which ought to have sufficient total primary (coil + any external ballast) resistance to limit the current switched to around 4 amps or so MAX. REMEMBER EITHER excess current (over 4 maps) or a weak or mis sized condensor causes premature points burn up.

I suspect that coils primary (between lil + and - terminals) is under 2 ohms and that excess current is frying the points, or else the condensor is wayyyyy yy off size in microfarads to match up correctly with that coils inductance, hence no capacitive action, frying the points.

The other alternative would be to use the old 6 volt coil and an external ballast of around 1.5 to 1.85 ohms (typical sizes on those ignitions) and the stock condensor from IHC CUZ IM NOT TRUSTING THAT SUPPOSED DUAL PURPOSE COIL ONE BIT LOL

John T

[Log in to Reply]  [No Email]
Wicksfield

05-31-2006 06:52:50




Report to Moderator
 Re: M burning points in reply to Wicksfield, 05-31-2006 05:23:28  
The 12V coil I purchased is for use with or without external resistor.....I got it from TSC. I'll make all electrical tests this evening.

I've heard good things about electronic ignition. Should I just scrap the point set up now that I have 12V and go with the electronic igintion? Is my 12V coil for use with or without resistor usable with EI?

Thanks for everyone's input.



[Log in to Reply]  [No Email]
Bob M

05-31-2006 07:25:19




Report to Moderator
 Re: M burning points in reply to Wicksfield, 05-31-2006 06:52:50  
Hmmmm.... I've never seen a coil marked "for use with or without external resistor". In my limited experience they're either one or the other, but never both!

My recommendation would be to put the old coil back on and stick on a NEW ballast resistor. (Ask for one for a 70's era Chysler car - NAPA # 13ICR or equivalent). I've had this setup running on my Super M with the same set of points for 15+ years.

Personally I wouldn't spend the $$$ on electronic ignition. The stock ignition - even after a 12 volt conversion - is more than adequate for your tractor. (OTOH once you go electronic you'll never need to mess with the points again!)

[Log in to Reply]  [No Email]
Wicksfield

05-31-2006 08:22:54




Report to Moderator
 Re: M burning points in reply to Bob M, 05-31-2006 07:25:19  
Bob M, I may be wrong. The coil may be marked for use with external resistor. I'm at work (yea right) and cannot check right now.



[Log in to Reply]  [No Email]
John T

05-31-2006 06:22:24




Report to Moderator
 Re: M burning points in reply to Wicksfield, 05-31-2006 05:23:28  
Wicks, Im kinda thinkin along the same lines as Bob, heres some thoughts: Premature points burn up is often caused from excess current (around 4 amps or so should be the max) or a bad or not grounded condensor. You may need to check the primary resistance of that new "12 volt coil" as measured between its lil + and - terminals as it should be around 2.5 to 3.5 ohms or so such that the current is in that 4 amps range. The reason I say that is cuz some so called 12 volt coils are actually "12 volts" others "12 volts for use with an external ballast resistor" and some "12 volts NO external ballast required" YOU NEED ONE LABELED (or designed) 12 VOLTS NO EXTERNAL BALLAST. If your coil is one of those "12 volts for use with an external ballast" its in reality a 6 volt coil (primary resistance around 1.2 to 1.5 ohms) and your points are switching excess current and will burn up prematurely plus run hot. Some automotive 12 volt coils are lower primary resistance then the 3 ohms or so required for many points type ignitions, so to be safe, you need to measure your coils primary resistance and you need at least 2.5 preferably 3 ohms to protect the points as designed for.

If you can barely hold your hand on the coil cuz its so hot it may be a 6 volt (12 for use with external ballast)coil!!!!

Its hard to really test a condensor with an ohmmeter, you need a real condensor tester. An ohmmeter can tell if its bad/shorted and capacitance to some degree, but if in doubt have it tested or get a new one. Make sure its connected good to the points terminal and has a good case ground also.

The points need to close nice n even n flush with each other or they burn up quicker.

Let us know

John T

[Log in to Reply]  [No Email]
Bob M

05-31-2006 05:42:33




Report to Moderator
 Re: M burning points in reply to Wicksfield, 05-31-2006 05:23:28  
That’s a puzzler – especially after you made the switch to the “12 volt” coil! A few things however to check:

1 – (Long shot...) Are you certain the condensers are good? Use the ohms function on a VOM or DVM and measure the resistance between the pigtail and the can: On a good condenser when the test leads make contact the meter will show very low resistance. Resistance will then rise over a period of several seconds into the megohm range.

2 – Is the condenser can solidly grounded to the breaker plate? (A poor or no ground here gives a weak spark and will burn points quickly.)

3 – When the engine stopped and the ignition on, measure the current in the coil primary. You should see 2 - 3 amps or. A reading of 5 amps or more means the resistance of the ballast resistor is wrong (too low). Burned points and an overheated coil can be the result.

[Log in to Reply]  [No Email]
300Randy

05-31-2006 05:42:32




Report to Moderator
 Re: M burning points in reply to Wicksfield, 05-31-2006 05:23:28  
A guy I work with said that any kind of petroleum oil or grease near the points will make them burn quick. He said to use only a special grease that is meant for distributor shaft and shaft follower on the points.



[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