JD 40C crawler engine quitting

[RawkFarmer]

Hi folks. I have a fairly new to me 40 c gasoline engine crawler that yesterday developed an issue whereby after starting and running fine for about 5 minutes it just died. It starts again with some effort, but then dies again after a minute or two.

I have checked the fuel flow at the carb and it seems to be flowing to the carb just fine. I ran it with the fuel cap off to check if it was a venting issue, but it still died. Any suggestions as to what to check next? It acts like it's starving out, but the steady flow I saw would discount that I think. Thank you!

 

[deeretails]

The brass inlet fitting in the carb. should have a screen in it. Not unusual for the screen to plug up, and the last thing most people check.

 

[Russ from MN]

Possibly the ignition coil, is it hot after it dies?

 

[J Hamilton]

Might be a bad or failing condenser

 

[RawkFarmer]

Thank you for these suggestions: I will check the brass fuel screen, coil & condenser and report back.

 

[RawkFarmer]

Hi folks: here's what I checked today:
1. Fuel inlet screen: I took off the hard line and there was no screen at either end.

2. Coil is not heating up.

3. I used some choke to start it this time ( I haven't had to usually) and with the choke out I noticed that it seemed to be moving the governor linkage in and out. With the choke in, it died out pretty quickly. So maybe the issue is the governor linkage being out of adjustment?

This post was edited by RawkFarmer on 06/26/2022 at 12:40 pm.

 

[RawkFarmer]

This post was edited by RawkFarmer on 06/26/2022 at 12:42 pm.

 

[Jim.ME]

(quoted from post at 15:30:48 06/26/22) Hi folks: here's what I checked today:
1. Fuel inlet screen: I took off the hard line and there was no screen at either end. [color=red:1a375077ea]Does this mean you removed the fitting from the carb and checked for a screen? I have seen the inlet to sediment bowls plugged, did you remove the sediment bowl from the tank and see that the passage in it was not restricted?
[/color:1a375077ea]
2. Coil is not heating up.

3. I used some choke to start it this time ( I haven't had to usually) and with the choke out I noticed that it seemed to be moving the governor linkage in and out. With the choke in, it died out pretty quickly. So maybe the issue is the governor linkage being out of adjustment? [color=red:1a375077ea]I do not see the choke being connected to the governor.[/color:1a375077ea]

This post was edited by RawkFarmer on 06/26/2022 at 12:40 pm.

 

[RawkFarmer]

Thanks, Jim: I'm not sure where the
screens are. I assume there is one inside
the carb body? And on the sediment bowl is
there one inside the tank and another in
the cap of the bowl? See arrows.

 

[RawkFarmer]

I can see the choke isn't connected to the governor, just that when I had the choke out, the governor was moving in and out. When I pushed the choke in the engine died pretty quickly afterwards.

 

[old]

Pull the carb drain plug and make sure you have a good steady flow of gas that will fill a pint jar in less then 3 minutes and 2 is even better. Could have some junk clogging the float needle

 

[Jim.ME]

Originally there would be a screen made as part of the 90 degree elbow threaded into the carb. That screen sticks into the fuel passage in the carb, you have to remove the 90 and the screen will come with it (if it is still there).

The parts book catalog does not show a screen sticking up into the tank as part of the sediment bowl. the only way to tell for sure is to remove the sediment bowl base from the tank and look. While it is off, check the passage to see that rust or crud has not restricted the passage on the tank side of the shut off valve. And of course, there should be the standard round disc screen at the top inside of the sediment glass bowl.

If you don't have it, SM2013 is the primary JD Service manual for all the 40 series tractors, you should have that one. There are two others that are related. SM2000 is an overview of older tractors and engines. SM2029 covers some accessories and electrical. eBay can be a good place to fined good used original manuals.

You can go to https://techpubs.deere.com/ , click on Equipment Publications. There search 40 as a model and you will see a number of possibilities of 40 model variations pick the one that matches yours by description and serial number and you should be able to find the Operator's Manual and download a copy for free. You can purchase the other manuals for your machine there if you wish.

 

[Hotflashjr]

I am going to say it sounds like a bad condensor or coil. Had this on many JD's of this age including my 40U. I have had bad condensors and coils out of the box as well.

Checking fuel screens is a great first step that is free of charge. I would next replace the condensor and clean the points. I have had good luck with Echlin from Napa.

 

[MSD]

Bad condenser. They will make you think it is a fuel issue but if it has fuel flow, it is a condenser. Those 40's don't burn much fuel so you don't need much of a flow to make them run.

 

[Russ from MN]

I would suspect the reason the governor rod was moving was that the engine was stumbling and the governor was trying to correct for it, that's what it is supposed to do. Have you done what Old suggested to see if you have fuel in the carburetor bowl, and good flow?