Pasquali 988 Clutch issue

   / Pasquali 988 Clutch issue #31  
Greetings Phil! I've been watching your saga. Disclaimer: Looking at pictures and being far away from your machine- I may be of no help at all, so take the following with a grain of salt!

Bottom line is the new clutch parts are not disengaging. Looks to me like the fingers could be adjusted out further. Try this: Measure from the bellhousing surface to the throwout bearing on the trans with the throwout at full retraction- in other words clutch pedal up. Now measure from bellhousing surface on engine to clutch fingers. The measurements should be very similar to each other, but with a little clearance between throwout and fingers.

Another possibility- is there slack or wear in the pedal pivot, or is the cable ready to break and stretching?

How did the new parts compare with the old? Was the disc thicker, the pressure plate worn, fingers worn down?

Again, it seems like if the fingers were adjusted away from the flywheel, there would be more available movement to pull the pressure plate away from the flywheel, releasing the clutch. Is the throwout bearing seated in the holder all the way giving enough room for this?

It worked once, It will work again! You Will get there! The frustrating part is chasing your tail while jumping thru hoops. Again, my suggestions are just shots in the dark, but I hope they help.:thumbsup::thumbsup:
 
   / Pasquali 988 Clutch issue
  • Thread Starter
#32  
Hi Ponderingjunkman thanks for your suggestions/ideas.

First not easy to make those measurements when its together, no access, though I should try to measure the distance the throw out bearing moves from stationary to when the peddle is pushed and then try pushing on the pressureplate manually to see how far they need to go to release the clutch.

The fingers are soposed to be 20mm out from the plate surface and I have them 21-22mm so they are already adjusted out more than they should be.

As for the pedal pivot, its solid, no slop/play and I bought a new cable so that isnt an issue.

As for comparing the old to the new parts, I sent the pressure plate back in for a core charge. The clutch was not much different, maybe a couple mm thinner than the new one. THe pressure plate fingers were bent on the old one and I caused that from over tightening the cable.

The problem is there isnt enough movement of teh throw out bearing. Im working on connecting teh cable higher up on the tranny arm to get more movement out of it but when I was thinking about it I think that will result in less movement, it needs to be lower on the arm to be more affective, ugh did alot of work for nothing....

Greetings Phil! I've been watching your saga. Disclaimer: Looking at pictures and being far away from your machine- I may be of no help at all, so take the following with a grain of salt!

Bottom line is the new clutch parts are not disengaging. Looks to me like the fingers could be adjusted out further. Try this: Measure from the bellhousing surface to the throwout bearing on the trans with the throwout at full retraction- in other words clutch pedal up. Now measure from bellhousing surface on engine to clutch fingers. The measurements should be very similar to each other, but with a little clearance between throwout and fingers.

Another possibility- is there slack or wear in the pedal pivot, or is the cable ready to break and stretching?

How did the new parts compare with the old? Was the disc thicker, the pressure plate worn, fingers worn down?

Again, it seems like if the fingers were adjusted away from the flywheel, there would be more available movement to pull the pressure plate away from the flywheel, releasing the clutch. Is the throwout bearing seated in the holder all the way giving enough room for this?

It worked once, It will work again! You Will get there! The frustrating part is chasing your tail while jumping thru hoops. Again, my suggestions are just shots in the dark, but I hope they help.:thumbsup::thumbsup:
 
   / Pasquali 988 Clutch issue #33  
Hey Phil!
The measurements I suggested were intended to be done while apart- There is no way to do that assembled!:D What you want to find out is how far the fingers would be from the throwout bearing surface. To do this, you need to go from a common reference surface like the bellhousing surface on both the engine and the trans. So lets say the fingers are "x" inches above the bellhousing surface on the engine, and the throwout bearing is "y" inches below the bellhousing surface of the trans. "y" minus "x" is the clearance between the fingers and throwout. I imagine there should be clearance, but it should not be more than a 32nd of an inch.(Don't know if that is accurate, but the clearance doesn't seem like it should be large)
If the clearance is large, adjust the fingers to tighten the clearance! This will give the throwout the largest effective travel. Read that again!

To quote you "The problem is there isnt enough movement of teh throw out bearing."
This could be because the fingers are not supposed(for whatever reason- ) to be adjusted to 20mm

Lets just say that they were intended to be at 25 to 28mm. That would add 5-8 More mm of movement of the throwout bearing

Now- why would the fingers be adjusted differently from 20mm? Several reasons: The parts could be made differently- ie pivots in slightly different locations(alters geometry) - The design may be different/changed from what the manual covers- The manual could be wrong - The reference point could be wrong. So you have to see what works for the functionality of the machine, not what you think it may be. The best way to do this is to measure as I detailed above.

You are correct to be cautious about bending the fingers again. However, it seems like the reason they bent in the first place is because they were adjusted too far down(due to wear) and bottomed out in their travel against the pressure plate. So tightening the cable only tried to push them further against the bottom, bending them. If the are adjusted higher, they will be further from bottoming and bending- I think!

Again, this could all be incorrect- as it is tough to make these sorts of calls from a distance. But with two areas of adjustment- the cable and the fingers- The solution has to be in one of those. And you have already tried the cable...:thumbsup:
PLease don't hesitate to ask me to clarify anything- I'll do my best!;)
 
   / Pasquali 988 Clutch issue
  • Thread Starter
#34  
Hi ok we are on the same page, I didnt want to have to take the engine off again, getting old doing it. So I did what you suggested but before going to that and pulling the motor I tried a few things. To try and get more movement from the clutch peddle to move the throw out bearing more I removed a rubber bumper that kept the peddle down about 1/4 inch and then I also bent the peddle itself some so it could be pushed down a bit more, 1/8 to 1/4 inch so now the peddle moved at least 3/8" more.

I tested and still engine did not dis-engage. I then adjusted where the clutch cable connected to the arm, I moved its attachment point 1" down so it would pull and move it more, harder to move but more total throw, so there should be more movement of the throw out bearing. Tested again and the motor still will not dis-engage.

Now since I did not want to assemble it all and maybe have to tear it down again I am testing the clutch without the engine running. I am having someone push and hold the clutch peddle down with the tranny in gear and then I turn the engine over from the crank shaft nut on the front of the engine. My expectation is the tractor would not move but it does. Is this a false assumption??

So with no luck I pulled the motor again and made some measurements. Still with the clutch cable connected and adjusted to where it should be (actually its a bit too tight) I measured the distance from the throw out bearing to the bell housing surface. Peddle not pressed the distance is 3 1/4" and with the peddle pushed in the distance was 2 11/16 So a total distance of movement of 9/16" of an inch.

Measuring the tips of the fingers to the mounting surface on the engine they are 3 1/4" so again I have the cable too tight but was trying to squeak out all the movement.

Another measurement I made was from the bell housing surface to the surface of the throwout bearing where the arms that move the throw out bearing touch and found that one side is 1/8" further back than the other, so I think one of the Arms that move the throw out bearing is either bent or worn down more than the other one. The surface on the back of the throw out bearing where the arm pushes has small grooves in them but not even a mm deep I dont think.

Now the other item I think is an issue is where the throw out bearing is riding on the two guide posts that keep the throw out bearing in place. THis first picture is of it in the rest spot, where the cable is adjust to have the throw out bearing just touching the fingers.

http://i103.photobucket.com/albums/m132/mjenphil/Pasquali Tractor/CIMG4558.jpg

Compare it to this picture with the peddle fully depressed. THe throw out bearing is almost coming off of the guide pins. If it moved any more it would come off I think.

http://i103.photobucket.com/albums/m132/mjenphil/Pasquali Tractor/CIMG4559.jpg

Close up of one side

http://i103.photobucket.com/albums/m132/mjenphil/Pasquali Tractor/CIMG4560.jpg

So, now Im thinking the arms that move the throw out bearing are worn down and not evenly. I am thinking if they were to be built up with weld and then machined to be at the same height as each other that may fix my issue? IE if the throw out bearing isn't pushed in evenly maybe its not able to release the clutch??

Otherwise I think there is plenty of movement by the throw out bearing, it moves more than 1/2 an inch. So could try adjusting the fingers on the pressure plate to be taller so they contact the throw out bearing earlier so the throw out bearing doesn't start to jump off of the guide posts. Another thought is maybe the pressure plate is not the right one for this model?? I do not have my old pressure plate, I sent it in for the core charge but If I recall it was basically identical but I cant compare them now.

Any thoughts/ideas anyone??

~ Phil
 
   / Pasquali 988 Clutch issue #35  
"So could try adjusting the fingers on the pressure plate to be taller so they contact the throw out bearing earlier so the throw out bearing doesn't start to jump off of the guide posts."

That is what I have been encouraging you to do!!

It is weird that the Throwout arms are uneven, but they may have bent as a result of the bottoming out of the fingers. I don't think that is causing the problem tho. Get them even(bend or weld as you said) Then adjust the fingers taller! Just be sure to slack the cable, otherwise you may have a clutch that will not engage- The opposite of what you have now.

Back the bearing up all the way- slack the cable, etc. Then measure throwout bearing to trans depth again, and set the fingers to that measurement.

Thanks for keeping us posted. Remember, if this were easy, everyone would do it!:thumbsup::D You will get it!
 
   / Pasquali 988 Clutch issue
  • Thread Starter
#36  
Ok I tore it apart again and did some measuring, I also started a thread in the general repair forum so I will continue it there.

Basically the forks are not different lenghts, I guess I was tired so that isnt an issue. But please switch over to this thread to read what I found and what IM thinking of doing.

New clutch installed and wont dis-engage the engine - TractorByNet.com

In short after taking a lot of measurments there is not a lot of room for the pressure plate to release and let the clutch disk spin, less than 2mm. I think this is the crux of my issue...

~ Phil
 
   / Pasquali 988 Clutch issue
  • Thread Starter
#37  
OK I think I have it working, now when I push in on the clutch and manually turn the crank shaft while in gear the tractor doesnt move so I think im ready to hook it all up and fire it up.

What I did is several things tips/suggestions from several people, sorry I have a poor memory so cant remember specifically who supplied each idea.

1 - Scuffed the new clutch disk with sand paper to take the high spots off.
2 - Removed the blockers on the throw out bearing guide pins that kept the throw out bearing from moving further back to allow it to have a longer throw without coming off of the guide pins.
3 - Measured the distance from the throw out bearing surface to the bell housing mounting surface and then adjusted the fingers to be about 1/8" away from that, doing #2 and #3 allows the fingers stand up more and then allow more movement before becoming flat and not providing any more movement.
4 - Moved the clutch cable mounting location lower on the arm to get more movement out of it.

I am able to press all the way down on the clutch and not come up against either the hard stop of the clutch arm or having it get harder to press like the fingers have no more room to move and are bending.

I have to work the next couple of evening so I probable wont get to finish assembling it till Saturday to try firing it up.

Thanks for all your suggestions/help.

~ Phil
 
   / Pasquali 988 Clutch issue #38  
Hi guys, sorry I missed all this while it was happening. You are correct Phil, the clutch tool is shaped the way it is so that you can spin the engine and ensure the three fingers are adjusted to the exact same height. When using the clutch adjustment tool, the two feet rest on the outside flange and the center of the tool is the height needed for the three arms. The two cut outs allow for the taller spring cups to pass underneath. The critical measurement is actually from the base of the feet (resting on the outside flange - roughly the plate height) and the center of the tool. Anything that is worn (throw out bearing center, bearing throw lever, etc.) will affect the amount of compression and there is really no room for wear with a new clutch package. The new pressure plates being sold out there as "improved" are a Cermag after market type, typical of a Kubota type plate. I have sent out about six replacements for these, as some users have had failures after a couple hundred hours of use. Customers that have gone back to the original style say they have a smoother engagement. Complaints about the older style are that the springs lose tension in time (which is true), but there are a lot of original plates still in use from the 70's and 80's. Phil, what I should have done (and didn't think of it earlier) is turned a new bearing center for you on the lathe with a thicker flange. I bet that would have done it. If you have to take the engine off again, please contact me and I will machine one up for you.

Just to mention that I just returned from Eugene, OR after buying out Gary Nash's remaining stock of Pasquali parts. Gary was the largest Pasquali dealer in the Western States (probably all of North America). We are building a pretty large inventory of parts, both old/new stock as well as some used pieces. You can write me directly at info@italiantractors.com or visit the site. We have a lot of useful information posted for those interested.

All the best,

Tom Brach
 
   / Pasquali 988 Clutch issue #39  
I have a Pasquali 988 that has the opposite clutch problem. It seems to slip badly in the higher gears. Won't take itself up a hill except in low range. Could this also be an adjustment problem or do I need to rebuild the clutch? I did find some place willing to sell parts in New Hampshire I believe. look for American Pasquali on the net. (33 NH Rte. 4A, Wilmot, NH 03287 | (603) 526-9493 | jack@pasqualitractor.com) Its been a year since I spoke with him.
 
 
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