[AJD] timing crash test.............

Dean VP deanvp at att.net
Tue Feb 15 18:39:33 PST 2005


Nick:

Wow!  Just be thankful no one got hurt. The rest can be fixed. 

I think it would be prudent to determine how you are measuring the coil. A
coil that truly reads 0 ohms will not produce a spark. So something doesn't
compute here or it is very intermittent. Typically a coil will have some
winding short out and reduce the output but not completely short out. What
ohm meter are you using and what range are you on when you measure the
resistance. Keep in mind measuring low resistance accurately requires a
pretty good VOM. I checked a couple of magneto coils I have around here,
unfortunately of unknown goodness and one known good coil and the resistance
from the button to ground ranged between 4.4 ohms to 4.6 ohms. The other
winding usually measured in the neighborhood of 0.6 ohms. 

However, having it run, but poorly, with back firing usually indicates poor
timing, or poor fuel. It still can be magneto related, such as the impulse
mechanism sticking, worn out bearings on the magneto, coils windings
breaking down at high voltage, intermittent connections or intermittent
shorts. You say the condenser is good but I don't recall you mentioning how
that was tested. Just because it is new doesn't necessarily mean it is good.


What cannot be ruled out yet either is sticking valves, carburetor issues,
etc but somehow confidence needs to be developed in the magneto. A magneto
can be tested quite nicely off the tractor. A magneto providing intermittent
spark may be due to the points being opened unequally or intermittently
because the shaft is floating around due to worn out bearings. Any
noticeable side to side movement in the lobed shaft that drives the points
would provide the kind of symptoms you are having. Somehow before trying to
actually start the tractor you need to get the magneto to consistently
produce spark. 

Dean A. Van Peursem
Snohomish, WA 98290

I'm a walking storeroom of facts..... I've just lost the key to the
storeroom door 


www.deerelegacy.com

http://members.cox.net/classicweb/email.htm



-----Original Message-----
From: antique-johndeere-bounces at lists.antique-tractor.com
[mailto:antique-johndeere-bounces at lists.antique-tractor.com] On Behalf Of
nick_solomon at infostations.com
Sent: Tuesday, February 15, 2005 5:30 PM
To: antique-johndeere at lists.antique-tractor.com
Subject: [AJD] timing crash test.............

well I continued the work of the last make shift mechanic and re soldered
the lead they had picked out of the coil, still wasent getting much of
anything, condensor tests fine. I have nobody here to help me pull start
it, and I could not think of one safe way to do it my self. so I pushed
the tractor away from the garage and was able to squeeze my truck by, and
pulled the tractor (in neutral) to an area that was out of the way.
while I was out there I decided to give it one more shot, I opened the pet
cocks and adjusted throttle and choke, stepped on the starter, it gave a
tremendous back fire AND STARTED, I had sometime while climbing on the
tractor pushed it into 6th gear and not noticed I could not get the clutch
disengaged, could not turn in time and ran into the back bumper of my
truck, very hard, it put a dent the width of the front of the tractor
pushed clear to the sheet metal of the truck, only scratching the paint
and primer down to bare cast on the pedestal of the tractor. by that time
I had gotten it out of gear. I am so pissed at my carelessness that I
could just spit. what if I had been standing next to the tractor pushing
on the starter, as I have done many times in the past, what if my fiance
had been there and gotten in front of the tractor. we learn from our
mistakes, but why do some of them have to be such gosh darn stupid ones.

well I shut it down to move my truck and assess the damamge and went to
start it again and couldent, Im back to little or no spark, checked into
coil again, coil still tests 0......... while it did run, it ran very
poor, lots of misfiring

somebody should take my truck and tractor away as a punishment.

Nick
sorry for venting about my stupidity



_______________________________________________
Antique-johndeere mailing list
http://www.antique-tractor.com/mailman/listinfo/antique-johndeere






More information about the AT mailing list