Trunion in 1810

[J-Mech]

Originally Posted by Pequeacubs

i will try to get a video tomorrow if the weather cooperates

[Pequeacubs]

https://www.youtube.com/watch?v=MwIvwn6ceak

https://www.youtube.com/watch?v=ffZ3M0D9YIQ

i hope these links work

[J-Mech]

Ok.... well... I don't recall having one do this before.

Questions:
* Someone already asked this and you never answered. How was it before replacing the springs? Is that the reason you replaced them, the noise?

* Where did you get the springs? Cub Cadet, I assume? (Just making sure they are the correct part.)

* Did you repair the trunion spring holding "square"? Are the caps loose in it?

* I think I see the smaller spring in there, but it is present, correct?

* Is this a new issue? A new to you tractor that had this issue already? How about a back story..... When did it start?


Lets go with some answers to that stuff to get started.

[Pequeacubs]

i had the tractor for four year only recently have the issue start before i put the hydro lift in the trunion square was not worn i put new cc spring and cap assemblies in to try to fix issue. i put the implement relief in from the donor tractor. the only other strange thing is when raising the lift the whole way up the tractor will bump forward.

[Pequeacubs]

i forgot that the caps are tight in the trunion

[J-Mech]

Originally Posted by Pequeacubs

i had the tractor for four year only recently have the issue start before i put the hydro lift in the trunion square was not worn i put new cc spring and cap assemblies in to try to fix issue. i put the implement relief in from the donor tractor. the only other strange thing is when raising the lift the whole way up the tractor will bump forward.

How about some punctuation...... I can't follow any of what you said.

[Pequeacubs]

I had the tractor for four years. The issue started s little bit before I put the hydro lift in. The trunnion square was not worn. I put new cc spring and cap assemblies in to try to fix issue. I changed over the implement relief in from the donor tractor. The only other strange thing is when raising the lift the whole way up the tractor will bump forward.

[J-Mech]

Originally Posted by Pequeacubs

I had the tractor for four years. The issue started s little bit before I put the hydro lift in. The trunnion square was not worn. I put new cc spring and cap assemblies in to try to fix issue. I changed over the implement relief in from the donor tractor. The only other strange thing is when raising the lift the whole way up the tractor will bump forward.

That makes much more sense. Thank you!

So, it did start this before you added hydraulic lift.
Has it progressively gotten worse?

The tractor "bumping" forward when raising the lift isn't uncommon, but it is likely that your neutral position isn't adjusted properly.


Ok... so since we aren't really getting anywhere with this, I'll offer up my SWAG. I'm thinking that it is one of two things. Either the charge pump is cavitating, or your pump has some odd wear that is causing the chatter.

Cavitation:
The charge pump is sucking air. Check the fittings on the suction line/pipe between the lower case and the hydro. You may need to replace the front seal and the o-ring on the charge pump. While it's apart, check the charge pump for uneven wear.

Worn pump:
It is possible that the slipper pads are deteriorating. They may not be flat anymore and when the pump is loaded (sudden direction change) the pads lose the oil film provided on them and "grate" on the ramp they ride on.

It is also possible that the pins that hold the swashplate shaft to to the control rod are failing, causing the swashplate to "chatter". It then works it's way through the control rod and to the springs.


So, either way, it is likely that you will have to disassemble the pump in order to find the cause. It is also possible that since you have no experience with the internals of a piston pump, you won't be able to find the problem. It is possible that even I would have trouble spotting the issue. FWIW, I would suggest shimming or otherwise tightening up the springs a bit more and see if it goes away. Stiffer spring may work. The purpose of the springs are for operator comfort and ease of control. They in no way affect the internal operation of the hydrostatic trans. The other choice you have is to replace the pump. I just can't see anything in the video that would cause the swashplate shaft to chatter like that, that isn't an internal issue. Something inside has got to be wearing out.

[johncub7172]

Ya, I destroyed a good unit by attempting to remove the pump swash plate. That little pin came out the back of the aluminum housing! Ooops. So now I have a good reference unit to go by.

The service manual describes a basic parts check. I, personally feel taking apart the pump can be easy.

Also, I did not see a smaller spring inside the larger spring in the video. It's got to be something!!

[Pequeacubs]

the smaller springs is inside the big springs. btw i do understand how the hydro pumps work internally. i was just hoping there was something small i was over looking before tearing into the pump. I thought this was a friendly site but assuming some one does not know something is not right.