4050 issue

Ben Hucks · Sep 1, 2012

Posted up a while back but needing some more info. Here's the issue. Tractor is a 1985 4050 with a 466 non asp motor. Starts great when cold. Can run the tractor all day just running around all day like moving bales. Problem arises when you really work it. After it gets good and hot after you shut it off it is very hard or impossible to start. Tractor will turn over but seems to have hydraulic pressure keeping the motor from turning free. Reason I say that is I can crank the steering wheel back and forth an free the motor up to where it will sometimes start. Have replaced the injector pump charge pump battery cables and relay. I have had a lot of hydraulic work done about a year and a half ago. Starting to think he didn't get something back in there right. Been having this problem for about 9 months. Just weeding things out before going back in. Thanks for any ideas you guys have

jd110 · Sep 1, 2012

Lots of possibilities. Could be a weak starter. Could be insufficient cranking ampps in batteries. Can be problem with hydraulics also. If you start tractor cold and let it idle, do any hydraulic components get hot after 10 minutes or so?Check pressure line from right side of pump. If it is warm/hot, follow the line back to rear of fram rail. It t's off there and a line goes to steering and brakes and another line goes to three point and selective control valves. Follow the heat to the bad component.

Kyle_in_Tex · Sep 1, 2012

I know there is a situation that involves weak hydraulics after an hour of hard work. This means tractor should be split and new sender pump put into tranny. Does not sound like your issue except the 1 hour and hot symptoms.

Tx Jim · Sep 2, 2012

A cheap and simple diagnostics step would be to install one of the hyd pump destroking screws. If utilizing the DS screw helped hot starting then that would eliminate other possibilities.
AR96625 FIELD INSTALLATION KIT, SCREW, HYD ADD 15.01 USD
RE13271 SCREW, PUMP SHUT-OFF ASSEMBLY ADD 38.21 USD

Ben Hucks · Sep 2, 2012

Once you install the screw is that something that can be left in or does it have to be installed every time you use it.

Tx Jim · Sep 3, 2012

Once the screw is installed then anytime the engine is slow to start screw the screw down to destroke the hyd pump. All things equal engine should spin over faster. After engine starts just loosen the screw to allow pump to pump oil.

jd110 · Sep 3, 2012

Some tractors came from the factory with destroking screw already installed. Check before buying one.

Ben Hucks · Sep 3, 2012

Thanks for the info guys Allot of help. I have been reading and there is a starter that has reduction gears that will help spinning the motor faster. What's your opinion. Also seems to help going with on 12 volt battery verses 2 6 volt. What's your opinion on that.

Tx Jim · Sep 4, 2012

jd110 said:
Some tractors came from the factory with destroking screw already installed. Check before buying one.

Maybe some industrial model came with a DS screw but I don't remember ever seeing an ag tractor that had one from the factory at least not down here in Tx.

buickanddeere · Sep 5, 2012

Looking for more starting power while there is a hydraulic load. Is like putting more wood in the stove to compensate for somebody leaving a door open.
That said , measure voltage at the starter while cranking?
If you really want the highest powered 12V starter to wail the engine over . Install a Delco 44MT. And two of the highest CCA batteries that can be crammed into the battery boxes.
Battery cables and chassis connection have to actually measure good, not just look good.
Battery to chassis/ground connection should be moved to a starter mounting bolt.