4020 Hard Starting Update

2510Paul

Well-known Member
I got lots of responses on this topic so I thought I would post an update. It will also help me summarize my results.

Picture 1 is laser RPM sensor on the Crank Shaft Dampener.
Picture 2 are leads to sense battery voltage, right hand 12 volt battery connected in parallel with left hand battery.
Picture 3 is BatteryMinder connected to left hand battery for charging over night.
Picture 4 are leads to sense the voltage the starter is seeing when cranking. Green wire to starter bolt, Red to Starter voltage.

I will summarize this as three tests:

Test 1, Coupler on Main Pump Connected.
No Load Battery Voltage, 13.96 Volts, charged over night on BatteryMinder.
Starter Voltage while cranking, 10-11 volts, lots of ripple. DMM.
RPM: 88
Turned the steering wheel in both directions, no cranking difference, front wheels turned with steering wheel.

Test 2, Coupler on Main Pump NOT Connected.
No Load Battery Voltage, 12.82 Volts, this test immediately followed Test 1.
Starter Voltage while cranking, 10.9-11 volts, much reduced ripple, DMM
RPM: 134
Did not move Steering Wheel.

Test 3 (There were two cranking events in this test.), Coupler on Main Pump Connected.
No Load Battery Voltage, 12.64 Volts, this test immediately followed Test 2.
Starter Voltage while cranking, 9.8-10.1 volts, much reduced ripple, DMM. (Reconnected DMM and cranked a second time to get this reading.)
Battery Voltage while cranking, 10.4-10.5 volts. (First Test 3 Cranking.)
RPM: 82
Did not move Steering Wheel.

Batteries: Northern
CCA at 32 F: 560
CCA at 0 F: 475
Reserve Capacity: 120
Age unknown.

Starter, Supplied by All States at 24 volt to 12 volt conversion 2 years ago. Starter went to shop this last summer, insulation issues repaired. No further detail supplied.

Connections: Battery Post and lugs abrasively cleaned. Voltage drop in both hot and ground legs together did not exceed a volt during several checks of this drop. I am thinking the connections are good.

My Comments:
Owner would like to go to the larger rectangular batteries like you find on a 50 series tractor, 1140 CCA at 32 F. JD Strongbox battery, long and thin, would supply almost 200 additional CCA (each battery) at each temperature over the long and thin Northern Batteries. While the Northern batteries seem to be doing reasonably well, I plan to suggest the JD Strongbox batteries. I won't have to build a new battery box.

I rather suspect the starter as the bigger issue. While it turns, it turns slow even with over 10 volts at the starter. Disconnecting the Main Pump did increase RPMS but still below the 150-200 RPM someone suggested. I wish I had a DC current sensor.
Someone commented how small the battery appeared. Someone commented these "conversion" starters were 24v starters converted to 12 volts. Can anyone confirm this? The replacement batteries the Dealership recommended were much longer, AR501444 or AR501446. I'll be recommending one of these, perhaps with the Northern Batteries first.

I would appreciate any comments regarding my tests and comments. Perhaps something I did is not proper or there are other conclusions I am not seeing.


Now that I have the tractor running again I will continue my Power Steering Tests.

Recall I did an "air in the system" test, it failed.

I have followed on with a leakage test of the Steering Motor. The hose from the pinion cavity to the reservoir did not spill any oil with the tractor running and being steered. Even though we all agree the seals on the pinions are old they do not appear to be leaking under pressure. So this test passed.

Tomorrow I plan to run the procedure to get the air out of the system. If this does not solve my problem with the steering I will be contacting Tim S about "what's next" and the costs of possibly asking him to re-build the Steering Valve.

Thanks.

Paul
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You can cap the steering supply line to isolate it..just a thought to prove it,,and if it is the problem I would be glad to rebuilt it for you..
 
Oh my, you jumped ahead of me in understanding Tim. So if I cap that line what do I look for? Thanks. Paul
 
I have had two of those starters supplied by All States, I wasn't very impressed with either. Have you considered trying a different starter?

I've also had poor experiences with the braided ground cables provided. Have you checked the ends of those? are they grounded to the case, or to the top cover of the transmission? Does the end of either of the ground cables get warm after cranking?

I'm probably several steps behind you in your troubleshooting, but those are issues I've had in the past.
 
Caping the valve and you still have the same problem means the valve is not the issue.
 
Upon rereading your post, you picked up considerable RPM by disconnecting the hydraulic pump... Either you do indeed have a hydraulic issue, or the starter is weak, and can't handle any additional load. Would be interesting to see what the results are with another starter.
 
Actually that happens on all closed center tractors..I have a 30hp motor spinning my pump stand and it works it.
 
I am surprised that aftermarket companies have not come up with a cheap and tiddy electric destroke.
50 rpm cranking is always good to take.
 
Impressive and thorough diagnosis .One thing that is left is the starter even though it was in for inspection last summer.Shaking the wheel will accomplish about same as a pressure by pass.If they wont spin fast they are hard to start. If batteries are not problem and connections are good starter might be a place to at least check to rule out.I do know there can be a big difference in starters even when new or rebuilt.
 
Shaking the steering wheel only works if pressure to turn the wheels is quite low. If you have major weights hanging up front with tractor parked down hills and with 7.5-16 front tires sank 4 inches in frozen mud, I doubt you are helping much. The pump load is reduced then 2/3 of normal. Destroke will bring it to about 1/15.
 
You are wrong about the extra weight thing fdt860,,all that is needed is to bump the valve with a slight movement,,"Hogging" the wheel back and forth is doing more than is needed,,and strong starter is important,,and most over looked in a problem like this,,especially when cold weather is in the mix..
 
I still have the 12V Delco conversion starter on my 4020. I live in a cold environment and I put new bearings and brushes in my Delco starter every 3 years regardless if I need them or not.

The reason is that I can get my 4020 started on a 10 degree day with no heat, I do not like doing this but if needed I can.

I also built a new battery box and placed it on the side frames. I use a standard truck batteries with offer more CCA's. Night and day difference when starting in cold weather. The bigger batteries does not crank any faster, it maintains the cranking speed longer.

I'm firm believer in a destocking screw as this will eliminate more hydraulic pressure than whipping the steering wheel back and forth. Yes whipping the wheel makes a big difference, but a destroke screw makes an even bigger difference. As for having to get back off the tractor to release the destoke screw, oh well as I like to let my tractors warm up for a few minutes when it is this cold out.
 
I see I had an error in one of my paragraphs.

Under My Comments:

"The replacement batteries the Dealership recommended" should have been "The replacement Starters the ......"

Paul
 

Yes JD offers an elect de-stroking kit but it's not cheap.
RE40463 HYDRAULIC PUMP ELEC ADD 756.30 USD

JD also offers an elect DS kit for tractors built in Mannheim factory with the 2.4 ci in pump that I think would work but no price is listed.
AL38774 Solenoid Valve ADD Contact Dealer

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