lister peter gearbox failure help

[tired old pirate]

just had a boat pull in behind me with a knackered gearbox I think, would appreciate a few opinions. The guy just bought the boat and has a deadline to meet getting to rugby ! prop shaft will turn freely, engine runs fine but when in neutral still turns the shaft slowly, when you put it into gear it sort of stalls,gearbox makes a clunky noise and stalls the engine. have diagnosed a broken clutch and recomended we get an engineer to have a look in the morn. Any ideas from anyone? anyone nearish milton keynes got a lister peter gearbox under their bed?

[mayalld]

just had a boat pull in behind me with a knackered gearbox I think, would appreciate a few opinions. The guy just bought the boat and has a deadline to meet getting to rugby ! prop shaft will turn freely, engine runs fine but when in neutral still turns the shaft slowly, when you put it into gear it sort of stalls,gearbox makes a clunky noise and stalls the engine. have diagnosed a broken clutch and recomended we get an engineer to have a look in the morn. Any ideas from anyone? anyone nearish milton keynes got a lister peter gearbox under their bed?

Oh yes indeedy!

 

Is this a lister LH150/LM100 gearbox?

 

The first thing to check is that there is sufficient oil. Running short of oil makes them do wierd things, like refusing to disengage forward gear, or engaging forward and reverse gear at the same time (causing the stall).

 

Next prospect is that the reverse gear brake band is too tight. Remove the top cover, Manually disengage forward gear by replacing the central short bolt in the plate on the portside rear of the box with a longer bolt from the top of the box, locate the reverse adjustment (it is located under the dome on the top cover). the ad it should be adjusted so that the brake band is *just* causing resistance to movement, then slacken by half a turn.

 

Final possibility is that the circlip holding the cone clutch in place has come adrift. This will mean stripping the box, but it isn't difficult (I did it!). The fact that the prop shaft turns freely suggests that this may be the one (with a Lister box, the shaft should NOT turn freely when the engine is stopped, but should turn freely when in neutral with engine running

 

It sounds complex, but the manual has some good diagrams that will enable anybody who can wield a spanner to fix it

Edited August 4, 2007 by mayalld

[tired old pirate]

Oh yes indeedy!

 

Is this a lister LH150/LM100 gearbox?

 

The first thing to check is that there is sufficient oil. Running short of oil makes them do wierd things, like refusing to disengage forward gear, or engaging forward and reverse gear at the same time (causing the stall).

 

Next prospect is that the reverse gear brake band is too tight. Remove the top cover, Manually disengage forward gear by replacing the central short bolt in the plate on the portside rear of the box with a longer bolt from the top of the box, locate the reverse adjustment (it is located under the dome on the top cover). the ad it should be adjusted so that the brake band is *just* causing resistance to movement, then slacken by half a turn.

 

Final possibility is that the circlip holding the cone clutch in place has come adrift. This will mean stripping the box, but it isn't difficult (I did it!). The fact that the prop shaft turns freely suggests that this may be the one (with a Lister box, the shaft should NOT turn freely when the engine is stopped, but should turn freely when in neutral with engine running

 

It sounds complex, but the manual has some good diagrams that will enable anybody who can wield a spanner to fix it

 

fanatastic reply, thanks. I'll have a go with the guy tommorow, can I come back to you on this one tommorow? I'll get the full details of the box in the morn from the manual.

should the propshaft still turn when in neutral? mine dosn't! this one does. In neutral it is turning theprop slowly, as soon as you put any significant power on it goes clonk and stalls, odd looking movement from the clutch cable too which is hard to describe.

On the oil point wher on earth is the filler and dipstick! couldnt find one anywhere, I'm assuming that it does run on automatic transmission fluid!?

The poor folk on the boat have not lots of money and they are on the way to rugby on a deadline. Would love to help them out.

[Tootles]

fanatastic reply, thanks. I'll have a go with the guy tommorow, can I come back to you on this one tommorow? I'll get the full details of the box in the morn from the manual.

should the propshaft still turn when in neutral? mine dosn't! this one does. In neutral it is turning theprop slowly, as soon as you put any significant power on it goes clonk and stalls, odd looking movement from the clutch cable too which is hard to describe.

On the oil point wher on earth is the filler and dipstick! couldnt find one anywhere, I'm assuming that it does run on automatic transmission fluid!?

The poor folk on the boat have not lots of money and they are on the way to rugby on a deadline. Would love to help them out.

 

If it's a hydraulic LH150, (there should be a brass plate on the very top telling you this,) then next to it is a big brass hex-headed plug. The dipstick is a small headed 'pin', one level down from the plug, on the left looking from the back. Dont use ATF fluid!! You can use either EP 80 or 90 oil, (the stuff cars used to have in gearboxes), I have always used 90s. There is another dipstick right at the back, on the 'extended' unit. Thats for the reduction gear, so dont mistake it for the main stick.

Dave.

[mayalld]

fanatastic reply, thanks. I'll have a go with the guy tommorow, can I come back to you on this one tommorow? I'll get the full details of the box in the morn from the manual.

should the propshaft still turn when in neutral? mine dosn't! this one does. In neutral it is turning theprop slowly, as soon as you put any significant power on it goes clonk and stalls, odd looking movement from the clutch cable too which is hard to describe.

On the oil point wher on earth is the filler and dipstick! couldnt find one anywhere, I'm assuming that it does run on automatic transmission fluid!?

The poor folk on the boat have not lots of money and they are on the way to rugby on a deadline. Would love to help them out.

 

With a lister box, the propshaft should not turn when the engine is stopped.

 

It should turn freely in neutral when the engine is running.

 

Technically speaking, a lister box is (regardless of the selector position) in forward gear when the engine is stopped, because it needs oil pressure to move to neutral or reverse.

 

It doesn't run on ATF, it runs on EP80/90, and won't like ATF at all!

 

Feel free to come back to me once youve had a look at the box.

[tired old pirate]

With a lister box, the propshaft should not turn when the engine is stopped.

 

It should turn freely in neutral when the engine is running.

 

Technically speaking, a lister box is (regardless of the selector position) in forward gear when the engine is stopped, because it needs oil pressure to move to neutral or reverse.

 

It doesn't run on ATF, it runs on EP80/90, and won't like ATF at all!

 

Feel free to come back to me once youve had a look at the box.

 

just to let u know it ended up needig a new gearbox and got sorted. We stripped it and it was knackered. Thanks 4 all your help