I am fairly new to hydros. My tractors have been mainly manuals. I spent about 3 hours seat time mowing some tall grass with my B2150 HSD. Power is really good. It has more blowby than I would like at 700 hours, but I think it has had a hard life. The other thing that bothers me is the slack in the transmission when it goes from pulling to what I call hydro or engine braking. It is much more that my B6200, which was very tight when you backed off on the hydro. I did see the old clutch disc that the PO replaced before I bought the tractor. The splines in the center hub were about half worn out. I would have been suspicious of that, but the clutch has been changed. Are there other obvious places for slack to show up?
What causes slack in a HST drive train?
- Thread starter 300zx
- Start date
Bump. Anyone have an opinion or is this just something you have to live with as the tractor ages or wears?
John in VA
John in VA
Rob
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Did you see the old clutch before you had agreed to buy the 2150.
When i rebuilt my 71000hst i made a point of checking the clutch whilst i had the whole machine stripped down, it had covered 800 odd hours and was the original unit, in general it was in excellent condition with no issus to the splined centre fitting, also no issues with the drive shaft or bushes.
I did later find out the HST pump was a bin job as the splined shaft on the pump was allmost rounded off due to the coupling between the drive shaft and the hst pump had not been checked and was slowly getting looser until it had allmost worn down the shaft splines, thus causing a lot of slack in the drive , only the locating pin was keeping things together
But , the clutch end of the shaft was fine, maybe you have a similar issue along the drive shaft train or at the coupling on the HST pump causing a backlash effect at the clutch plate and on the splines.
Due to the way the driveshaft slides into the plate and then into a bush in the crankshaft i cant see why it would normally be able to wear down as you mention, unless the plate wasnt aligned properly or similar, i think you may need to check the whole drive train and eliminate parts as you go.
Good luck & hope you get it sorted , sorry cant be of any more help to you on this as i'm no expert, just my experience from problem i had with my own HST.
PS, this is another example of why i prefer manual over HST, just my opinion for record..
When i rebuilt my 71000hst i made a point of checking the clutch whilst i had the whole machine stripped down, it had covered 800 odd hours and was the original unit, in general it was in excellent condition with no issus to the splined centre fitting, also no issues with the drive shaft or bushes.
I did later find out the HST pump was a bin job as the splined shaft on the pump was allmost rounded off due to the coupling between the drive shaft and the hst pump had not been checked and was slowly getting looser until it had allmost worn down the shaft splines, thus causing a lot of slack in the drive , only the locating pin was keeping things together
But , the clutch end of the shaft was fine, maybe you have a similar issue along the drive shaft train or at the coupling on the HST pump causing a backlash effect at the clutch plate and on the splines.
Due to the way the driveshaft slides into the plate and then into a bush in the crankshaft i cant see why it would normally be able to wear down as you mention, unless the plate wasnt aligned properly or similar, i think you may need to check the whole drive train and eliminate parts as you go.
Good luck & hope you get it sorted , sorry cant be of any more help to you on this as i'm no expert, just my experience from problem i had with my own HST.
PS, this is another example of why i prefer manual over HST, just my opinion for record..
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Ouch! Splines do like to run greased. I don't think the propeller shaft is what's causing 300zx's problem though. In his machine that shaft runs between the engine and pump and is always spinning at engine speed unless the clutch is in. Failing splines in there wouldn't manifest as forward reverse slack.
My Cub Cadet felt a little it had drive line slop until I readjusted the linkage. The tractor would jerk forward changing directions unless you were very gentle with the lever. Do you suppose it could be that or are you sure feeling something more mechanical? There are plenty of other splines and gears farther back in the transmission that could be going.
My Cub Cadet felt a little it had drive line slop until I readjusted the linkage. The tractor would jerk forward changing directions unless you were very gentle with the lever. Do you suppose it could be that or are you sure feeling something more mechanical? There are plenty of other splines and gears farther back in the transmission that could be going.
Ouch is right on Rob's shaft. My tractor has been apart twice. Once to replace the pump and the other to replace the clutch. Both by the PO who bought the tractor inoperable just to get the FEL for his other B2150. I have not been into either and probably won't until winter. You are right, there are a lot of splined shafts and gears where back lash can build up. I was curious as to peoples experience and if there is a prevalent area. I will check for slack in the hydro control, but I am not optimistic since the backlash occurs even if you don't change the pedal position. I will get a picture of the old clutch plate. The center hub splines are almost gone. I am now anxious to see how the shaft looks!
John
John
cmustang
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B7100hst 50" tiller Dodge 2500 diesel 700 Grizzly 79 K5 blazer 40" Boggers
check if your rear hubs are tight to your axles my b7100 has some slack due to previous owner not keeping them tight