1969 JD 4020 Fuel Problems, Shutting Off

I have a 4020 tractor that I bought a month or so ago, I have never run it very long, maybe 5 mins max, not sure. I have been working to fix some leaks on the banjo fittings on the injection pump, took a while to get parts and had to do it twice.

Yesterday, I finished the last banjo fitting and started the tractor, tractor running great and no leaks. I am wiping up diesel around the injection pump and the tractor just shuts off. Like it just slowed down gradually and then shut off. It had been running less than 5 mins.

I thought I might have run it out of fuel, gauge does not work. I took a stick and checked and there was 6 inches at least on the stick, added 4 more gallons anyway.

Came back a bit later after charging the batteries a bit and it started right up. I let it run a couple of mins, shut it off and continued to let the batteries charge. Thought my problems were air or something after the banjo fitting repair.

Later in the afternoon, I started it to move it into the shelter. It started right up and I assumed the earlier shut off was a fluke. A couple of minutes later on my way to the shelter the tractor shuts off. Same symptoms, like it just idled down until it cut off.

Tried to restart it and it would not (did not try much, I know the batteries were not fully charged).

I am not sure what is going on, only thing I did was disconnect the banjo fittings one at a time and replace. Have no idea when fuel filters were replaced last. No idea how old fuel pump is. Seems to me it is starving for fuel. Not sure. I am pretty sure if I go out there this morning it will start and then do the same thing.

I'm not sure the small supply pump on the side of engine block is the right one, most I've seen on JD 3020/4020 don't like like what you have. The injection pump has it's
own vane pump inside and will try to draw fuel too, but it's not designed to on C model pump. It needs a working supply/feed pump.

Also make sure shutoff wire to pump is snug on little stud on pump. Can also be loose wire on relay behind side shield above starter.

May I ask how starter relay can cause a running engine to stop running?

I thought relay above starter only was utilized to help energize/engage starter but wasn't utilized to supply voltage to fuel solenoid on inj pump.

Wire to injector pump comes from the ignition switch.. When the tractor is running the wire needs 12
volts to hold plunger open in the solenoid.. Do you have 12 volts to solenoid when the tractor dies??

Little trick on the banjo washers, go buy
copper ones that fit in place of the steel
ones.

If the fuel filters are plugged it can act like that and after it sits a while it will sometimes
start again .

You are right on relay. That is no crank.

(quoted from post at 06:13:45 08/02/20)
May I ask how starter relay can cause a running engine to stop running?

I thought relay above starter only was utilized to help energize/engage starter but wasn't utilized to supply voltage to fuel solenoid on inj pump.

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Likely, he is confusing the BIG circuit breaker near the starter with a relay.

He wouldn't be the first to do that and post it here.

Very likely that your fuel filters are plugged up. My 4020 was eating them like crazy until I cleaned the tank.
Anyway, you should always have 2 fuel filters on hand if you need your tractor.

I think this might be it Dieseltech. When I was wiping up injection pump I would definitely bumped that wire. I checked it yesterday and it was barely connected. I crimped the end a bit and now it is stuck very snugly. I need to replace my positive battery terminal this morning and test it. But I think you hit the nail on the head.

***Sorry I meant to mention cornerpost in last post. ***

I think this might be it cornerpost. When I was wiping up injection pump I would definitely bumped that wire. I checked it yesterday and it was barely connected. I crimped the end a bit and now it is stuck very snugly. I need to replace my positive battery terminal this morning and test it. But I think you hit the nail on the head.

(quoted from post at 08:41:48 08/02/20) Also make sure shutoff wire to pump is snug on little stud on pump. Can also be loose wire on relay behind side shield above starter.

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I believe you were correct cornerpost, I crimped the connector a bit and shoved it on snugly. Started the tractor and initial indications are good. Ordering new fuel filters to get those baselined. Also will be checking every other thing mentioned here.

Thanks for tolerating a newbie. I would never have owned a 4020 if it wasn't for this forum.