226D Transmission Regulator Case Gasket Question

[normde2001]

' the clutch pedal only allowed about 3/4 of its normal travel as the last 1/4 has been obstructed"

Tell us about this. Which end of clutch pedal travel is obstructed? If the top end it has to be slipping.

 

[winston1]

Does anyone know if there are test ports on a PowerShift transmission to see if full pressure is arriving at various circuits?

Yes, there are test ports, at least on his 226D. Page 250-10-21 gives the procedure. Assuming HappyDaze has a manual based on his spring length information.

Since the manual gives no information about sealant I would not use any, if I did it would be a very light dose. You don't need any sealant getting in all those passages.


Do you have any freeplay at the top of the clutch pedal?

 

[rScotty]

I must have missed the beginning. Can someone explain again why the regulator case is taken apart in the first place? Was it leaking?

What were the original symptoms? And most importantly, what were the original internal clutch pack pressures from the test ports? And what are they now?
How does the manual clutch fee play even enter into this kind of problem?
Sorry to be so dense, am I just asking all the wrong questions?
Confused, rScotty

 

[winston1]

May need to read from post #1. HappyDaze thought the cover might be where his problem was. He has not done a pressure test. His tractor would quit moving, I suggested it could possibly be the clutch.

 

[HappyDaze]

It is/was slipping, most noted in reverse. Slow engaging in forward gears too but they engage eventually whereas in reverse it is happy to slip in all ranges. It will engage in reverse eventually in range 1, without a load.

SOLVED FOR NOW:
And here is something that seems to happen often in these 菟owershift slipping threads...I realized I had ignored the inertia brake adjustment but not much has been said about it so I didn稚 think too much about it.

It needed plenty of adjusting (see pics). Once I loosened the clutch pedal adjustment nuts and went through the motions of adjusting the clutch pedal freeplay (the manual says adjust the clutch first but it was already pretty much set correctly) then I made the correct adjustment to the inertia brake and now it (the transmission) works like it痴 supposed to. It痴 fine now. I don稚 really get it but I知 guessing it has something to do with the clutch pedal travel being limited on the down end?

Either way I知 going to remove the loader and the corrupted brackets and locate a proper mounting bracket that does not obstruct the pedals.

What does the inertia brake do? Could it have been the problem or is this like Clark Griswold痴 Christmas lights, as in did I do something else I didn稚 realize in the process and the inertia brake was just coincidental...?

 

[HappyDaze]

Here are photos of the adjustment that was made to the inertia brake:

Left one is before the adjustment and the right one is after FYI

 

[winston1]

Glad you are up and running. Only my opinion, I believe the inertia brake function is to slow down or stop the powershift clutches when the main clutch is depressed. Anyone know any different I would like to know. I sure have no idea why out of adjustment caused your tractor not to pull.

 

[rScotty]

Glad you are up and running. Only my opinion, I believe the inertia brake function is to slow down or stop the powershift clutches when the main clutch is depressed. Anyone know any different I would like to know. I sure have no idea why out of adjustment caused your tractor not to pull.

I don't know anything at all about the inertia brake. It's a real hole in my Yanmar knowledge. I've never worked on one and not sure I've even seen one. And I don't even know the how and why of the inertia brake adjustment as it interacts with the rest of the powershift tranny. The inertia brake gets scant coverage in what is otherwise a pretty good workshop manual. I'd sure like to know more about it if anyone has info.

In general, problems with powershift are rare. When there is a problem with powershift the first thing to do is to clean out the reusable lower hydraulic filter, replace the screw-on throwaway hydraulic filter, and put in new hydraulic oil. Lots of times that is all it takes - especially cleaning that lower reusable filter. If that doesn't help, the next step is to get a workshop manual and some inexpensive pressure gauges so that you can take pressure readings at the test ports on the regulator case cover. Doing that will pretty much tell you what's next.

If you need to go deeper than that, you also need to be a pretty good mechanic with a real Yanmar workshop manual and a clean place to work. And I expect that once you get done you are going to know more about powershift than I remember anyway. It's been a while ago for me.
Good Luck!
rScotty

 

[California]

...I believe the inertia brake function is to slow down or stop the powershift clutches when the main clutch is depressed. Anyone know any different I would like to know.

I didn't know there was anything adjustable as shown in HappyDaze's photos. But I wonder if this is related to a 'parking brake' effect I noticed in both of the YM186D's I have experience with. The later one has a noticeable braking force in neutral if I stop for something on mildly sloping plowed ground, enough braking that I don't need the manual brake lock. This effect is stronger than on the previous YM186D but that one had it to a noticeable degree. And starting off cold in the morning, either tractor has some feeling that it needs to warm up before brakes release. I thought I read somewhere that shifting the Powershift to neutral, routes fluid to two gears at once to provide a braking effect.

Does anyone know more about this?