d160 lost all hydro

[jnelkie 11]

Any suggestions on a 79 d160 that lost all hydrolics( forward, reverse, impliments) while I was moving dirt and I was able to push tractor with tow valve engaged. When I jacked up tractor and engaged forward or reverse and moved lifted wheel the pump made pulsating noise when I turned wheel by hand and it did spin but able to stop wheel by hand and when the wheel stopped moving the noise stopped. I spoke to a hydro repair shop and he said it sounds like there is not enough fluid getting to the pump and could be sucking air somewhere. I checked every valve I could externaly and cleaned the screen by removing motor with no good results. any help would be greatly appreciated.

[953 nut 55,836]

Is the coupler from the engine to the hydro in good condition?

[pfrederi 17,886]

[jnelkie 11]

I have checked the coupler and it turns the pump and the pump and manifold lines do warm up after running a while. When I loosen up the implement or charge plugs on top of the pump oil does come out. I removed and checked all valves on pump and acceleration valve on motor, replaced filter and oil and no luck. when tractor runs the pump is quite until you engage forward or reverse and 1 wheel is off ground and you turn the wheel by hand to get the wheel to start spinning the pump sounds like a fan with a wobble and the noise stops when wheel is not spinning. I was told it sounds like lack of fluid in the pump caused by a blockage or air being sucked in somewhere. I removed the hydro motor and the screen was clean and found no metal shavings.

Edited October 2, 2018 by jnelkie

[pfrederi 17,886]

As you have no lifts working and they are run by the Charge Pump Suspicion points to a problem with charge pump.  Can you do  a pressure test???

[Skipper 1,788]

Can you confirm that you have correct oil level?

 

If you loosen the filter, or take it off, and then start the engine, it should start pouring out a lot. If it does, the charge pump is moving oil. If not, I would loosen the connection closest to the charge pump and see if it comes out there. If not , I would check to see if the suction line could be blocked somehow. If not, you better break out the big toolbox

 

In short, back trace till you find a place where oil DOES flow, if that place exists, and work from there to find the problem, and the solution.

 

[jnelkie 11]

oil pours out if I loosen either one of the plugs on top of the pump and I know its flowing back to the motor because the manifold gets warm, which line is the suction line, thanks.

 

[Skipper 1,788]

If it flows, there is no need to check the suction line AFAISI.

 

If you have pressure and flow of oil, there must be something wrong else where.  Motor or trans.  It's not just a busted key in a hub I presume.

 

[pfrederi 17,886]

25 minutes ago, Skipper said:

If it flows, there is no need to check the suction line AFAISI.

 

If you have pressure and flow of oil, there must be something wrong else where.  Motor or trans.  It's not just a busted key in a hub I presume.

 

A hub key (or even a transaxle cross shaft key failure would not explain the loss of implement lift...

[Skipper 1,788]

That's right. I forgot about the lift not working.

 

I do not see any other option than loosening connectors in the system, and find out where there is, and where there ain't oil flow then.

Edited October 4, 2018 by Skipper

[bc.gold 3,403]

If your hydro is the C or inline series the pin that locks the charge pump gear onto the input shaft has probably sheared so the pump gear is now idle while the input shaft turns.

 

The pin will set you back a whole two bits.

 

This pin looks the same as a shear pin used on a boat prop.

[jnelkie 11]

would there still be oil flow if the pin was sheared even if it was low oil flow and is taking the pump off the only way to check? thanks

 

[pfrederi 17,886]

First off in a D series there is no pin.  The splines on the right are driven by the engine coupling  The center 2 operate teh charge pump (georotor) and the far left turn the piston block.

 

My suspicion is the drive coupling (the cast iron thing on the pump shaft) has stripped.  It will still cause the shaft to turn but it is slipping and not generating adequate pressure.

 

After a while I suppose the oil would warm up a bit.  When you opened the plugs on top of the pump was it running?  if so the oil should have come out under some pressure not just oozing.  

 

A charge pump pressure test is definitely in order.  Do you have access to a gauge??  I have one set up that you could borrow for postage....

 

Alternatively you could separate the engine and pump and inspect the splines in the coupling....

 

Edit: My bad teh charge pump is run by the splines on the left the Piston Block by those in the center!!!

Edited October 6, 2018 by pfrederi

[Machineguy 877]

Who was the manufacturer of the pumps used for the D-series tractors? 

[pfrederi 17,886]

Sundstrand

 

[jnelkie 11]

How much pressure should  there be on the  charge pump? And when engine runs alot of oil comes out of the implement and charge pump plugs when I loosened them but didnt want to take completely out because oil was already pouring out. Also in the manual it says if you can push the tractor when tow valve is closed and have no forward/reverse and no implement power it is somthing in the center section but what is the center section if anyone knows.

[pfrederi 17,886]

Pressure should be 70-150.  I looked through my manual can't find what you refer to as center section.  Can you point me to where you read it??..  Being able to push with push valve closed may be a check valve issue???

[jnelkie 11]

Page 48 has the hydrogear trouble shooting chart and the symptoms point to a malfunctioning valve in center section and  says to do a hydrogear tune up but I am unable to find the wheel-a-matic manual anywhere online.

[pfrederi 17,886]

Yours is not a hydro gear and I am pretty sure the piston to piston doesn't have that plug.  Will look into that.

[jnelkie 11]

Getting a pressure guage from a friend and in the meantime I removed charge plug and oil and air bubbles flow out a couple inchs high when at idle if that indicates anything. 

[953 nut 55,836]

1 hour ago, jnelkie said:

oil and air bubbles flow out a couple inchs high when at idle

Pressure at idle ought to be over 50 PSI. Are you sure the pump is rotating at the same speed as the engine? I'm thinking stripped coupling.

[jnelkie 11]

Moved engine to check coupler and splines and they are all there, nothing broke, next is to check pressure. 

[jnelkie 11]

Just talked to LJ fluid and told L J what happened and he said that it sounds like the spring and retainer in the motor cylender block came apart and happens on the motor more than it does on the pump. It's a inexpensive fix if thats what it is and they have lots of parts for the D series piston to piston pumps. Will keep you all informed.

[jnelkie 11]

This is what I found when I opened up the motor, L J fluid is a must go place for hard to figure out issues. Now its time to order parts.

[pfrederi 17,886]

Great that it is easily fixable!!!  Never would have guessed that as the problem