1937 Model D Issues

[JD60Standard]

I have been working on a 1937 John Deere D for the last few weeks. It is extremely hard to hand start and if I can get it running it has no power when under a load. It has a new Wico “C” magneto and the carb has been rebuilt and cleaned multiple times. If any of you could offer some insight about how to solve these problems, it would be greatly appreciated.

 

[Loosehandle]

Probably running on 1 cylinder, I'm not a big fan of the wico c. Did you get a new coil with the rebuild?

 

[JOCCO]

M

Probably running on 1 cylinder, I'm not a big fan of the wico c. Did you get a new coil with the rebuild?

Might not be all your issue but I am with Loosehandle, on the C mag.

 

[Fixingfarmer]

I agree on not loving the C as well after attempting to rebuild a couple Wico X is the ticket Cs I’ve had corrode worse inside where the cover screws go into the metal housing. When you say “new”…is it new new or just a different mag? If you have 2 you can likely make one good one with a complete rebuild kit that has all the internal parts and the cover hopefully one of the housings is good. I made the mistake of trying a different model C as well it was an hour drive and 50 bucks to go get it to pull it apart and it be junk.

Status of plugs? The hand start ones I have to keep them fresh I’m not a fan of spinning the flywheel on the smaller ones. You have reliefs on yours so it should spin ok.

Throttle at half by looking at the carb throttle?

New mag that was off timed at the lh impulse mark?

 

[JD60Standard]

The mag came from Rudy at RebuiltMags.com so I would assume it is rebuilt and not brand new, it does have good spark coming from both plug wires. The old plugs were fouled so I replaced but it did not make starting any easier. The tractor will start if I pull start it and it idles well once it’s running, it just has no power under load. I will verify that the mag is timed correctly next time I’m out at my shop.

 

[JOCCO]

First not putting Rudy or anyone else down. But sounds like impulse issue. or incorrect coupling, lag angle not set correctly. I have been through all this before. Best to call him on the mag. (yes, it will fire) on the bench as a rule.

 

[JOCCO]

I agree on not loving the C as well after attempting to rebuild a couple Wico X is the ticket Cs I’ve had corrode worse inside where the cover screws go into the metal housing. When you say “new”…is it new new or just a different mag? If you have 2 you can likely make one good one with a complete rebuild kit that has all the internal parts and the cover hopefully one of the housings is good. I made the mistake of trying a different model C as well it was an hour drive and 50 bucks to go get it to pull it apart and it be junk.

Status of plugs? The hand start ones I have to keep them fresh I’m not a fan of spinning the flywheel on the smaller ones. You have reliefs on yours so it should spin ok.

Throttle at half by looking at the carb throttle?

New mag that was off timed at the lh impulse mark?

I pretty much agree fixingfarmer.

 

[JD60Standard]

The engine also seems to flood quite badly, what is the proper float height for a DLTX16 carb?

 

[a49deere]

The engine also seems to flood quite badly, what is the proper float height for a DLTX16 carb?

3/4" from top of bowl

 

[JD60Standard]

3/4" from top of bowl

Thank you

 

[Mark-Ia]

My book says 3/8" below the top of the bowl.

 

[a49deere]

Thank you

let me clarify, 3/4" is fuel level below top of bowl, not float itself.

 

[Watthour]

FWIW, the '38 D I had come with a Edison-Splitdorf mag, which was a steep learning curve for me. Once I wrapped my head around that and got it dialed in, it was almost frightening how hot it was, even at hand-cranking speeds. A quarter-inch jump of cranking spark was not even breaking a sweat for it, AFTER the re-magnitzation and coupling setup.

 

[JD60Standard]

FWIW, the '38 D I had come with a Edison-Splitdorf mag, which was a steep learning curve for me. Once I wrapped my head around that and got it dialed in, it was almost frightening how hot it was, even at hand-cranking speeds. A quarter-inch jump of cranking spark was not even breaking a sweat for it, AFTER the re-magnitzation and coupling setup.

That’s the same Mag that was on the tractor when I purchased it, I may try to rebuild that Mag and see if it starts any easier than with the Wico C.

 

[JD60Standard]

I finally got my D so I can hand start it in a reasonable amount of cranks, the problem now is that it is backfiring a lot when it is idling, the engine seems to smooth out when it is running at higher speeds. It is also running very hot, I had it running for no more the 15 minutes and it had reached 200 degrees. I am thinking that there is a timing issue causing these problems, can the mag be adjusted while the engine is running?

 

[Fixingfarmer]

The same way you time a distributor. Loosen bolts on mag (there should be a slot) install timing light on the left spark plug aimed at your marks on the flywheel and side of the crankcase till they match up. It’s easiest carefully with 2 people but one can do it going back and forth rotating magneto housing then back to checking timing on the other side of tractor. Don’t touch wires or you might get bit.

The belt pulley is bigger on a D as well so again carefully.

That’s the best way I’ve found to time a 2 cylinder I’m not sure how many people bother to do it.

 

[JD60Standard]

Thanks, any recommendations for a timing light?

 

[Fixingfarmer]

 

[Fixingfarmer]

I’ve had a cheap one like that except it’s older than me some of the fancier ones probably aren’t necessary

 

[UnstyledB]

I finally got my D so I can hand start it in a reasonable amount of cranks, the problem now is that it is backfiring a lot when it is idling, the engine seems to smooth out when it is running at higher speeds. It is also running very hot, I had it running for no more the 15 minutes and it had reached 200 degrees. I am thinking that there is a timing issue causing these problems, can the mag be adjusted while the engine is running?

Does the tractor have water or antifreeze in the cooling system? If antifreeze, do you know how it was mixed before the system was filled? You can't pour a couple gallons of concrntrate in the system followed by water.....it will never mix properly and create a "plug" inthecooling system that will prevent proper circulation. The fix is as simple as draining the system which allows it to mix ans pouring it back in.

Does the backfiring happen all the time? Did you have thr head rebuilt? One time I traced backfiring to a valve sticking when the engine was hot.