Help Needed- Exmark Lazer Z keeps throwing belts.

[charford]

Hello,

I am new to this forumn, but at my last straw. I have an Exmark Lazer-Z- I think it is a 2002-2003. It is a Diesel, Model No. L-Z27DD724.

I bought this machine used last year and it ran great- but at the end of the season it busted a mule drive belt (it has 2) and also the clutch was smoked. We have a shop and are very mechanically included, but not experts. In any case we replaced the clutch and serviced the machine. This season started out and we blew another belt- thought maybe it was a bad batch, so we replaced them again and they broke again. At this point I started replacing damn near everything.

We replaced every single deck and idler pulley and bearing on the machine, and then it continued to throw belts.

We then tore the deck off and replaced the entire spindle assemblies, new blades, replaced the jack shaft bearings. We did not replace the jack shaft or triple pulley because they looked good. And the machine continued to throw belts.

Then we talked with a dealer and they mentioned maybe there was wear in the deck itself so we replaced the deck struts, pins, etc- re mounted, balanced, and measured the deck- I thought for sure that would get it as it tightened up the deck a great deal- also put on brand new belts for good measure- within an hour of mowing it threw another belt.

I have spent more in parts and belts than the machine is worth probably 3 times over at this point. Does anyone have any other ideas what could be causing this? The only thoughts I have at this point is that maybe the jack shaft is actually bent, but it really does not appear to be at all- or possibly the rear mule belt idler arm and spring? It doesn't seem like it would cause it, but there is a bit of play.

The dealer is at a loss, and basically has no further ideas. Where the deck mounts and pins are- there was a tad bit of wear on the holes on the deck (a bit egg shaped) but we are talking barely at all- I can't imagine it would be enough to cause the problem.

 

[BlazNT]

It is either the parts in the picture. You can test them by removing belts and spinning looking for any movement at all. Or its the clutch. Are you sure it in the correct position as in far enough up and or down. The belts should be level. Not uphill or downhill.

 

[charford]

I have inspected the triple jackshaft pulley many times- the pulley appears in great conditions, the shaft itself does not appear to be bent at all- I have replaced the bearings as well. It spins freely with no noise, straight, etc.

On the clutch- I will have to take a look at that, I do not think there is any adjustment there and it only bolts back on one way. I will double check that though- any other ideas, or everyone thinking the same thing?

Thanks for the ideas!

 

[charford]

I am not 100% sure what you mean by the adjustment on the clutch- on this machine the clutch is on the back of the motor. There isn't any adjustment that I can really see- here is a picture of the clutch- the belt of the left side is missing.

 

[BlazNT]

I guess I should have said it better. When you put it back on the shaft did it slide all the way up to the same position it was in when you took it off? I have see one get cocked and not go all the way back on. It was sitting too low and at a slight angle.

 

[valleyviewlawns]

Hello,

I am new to this forumn, but at my last straw. I have an Exmark Lazer-Z- I think it is a 2002-2003. It is a Diesel, Model No. L-Z27DD724.

I bought this machine used last year and it ran great- but at the end of the season it busted a mule drive belt (it has 2) and also the clutch was smoked. We have a shop and are very mechanically included, but not experts. In any case we replaced the clutch and serviced the machine. This season started out and we blew another belt- thought maybe it was a bad batch, so we replaced them again and they broke again. At this point I started replacing damn near everything.

We replaced every single deck and idler pulley and bearing on the machine, and then it continued to throw belts.

We then tore the deck off and replaced the entire spindle assemblies, new blades, replaced the jack shaft bearings. We did not replace the jack shaft or triple pulley because they looked good. And the machine continued to throw belts.

Then we talked with a dealer and they mentioned maybe there was wear in the deck itself so we replaced the deck struts, pins, etc- re mounted, balanced, and measured the deck- I thought for sure that would get it as it tightened up the deck a great deal- also put on brand new belts for good measure- within an hour of mowing it threw another belt.

I have spent more in parts and belts than the machine is worth probably 3 times over at this point. Does anyone have any other ideas what could be causing this? The only thoughts I have at this point is that maybe the jack shaft is actually bent, but it really does not appear to be at all- or possibly the rear mule belt idler arm and spring? It doesn't seem like it would cause it, but there is a bit of play.

The dealer is at a loss, and basically has no further ideas. Where the deck mounts and pins are- there was a tad bit of wear on the holes on the deck (a bit egg shaped) but we are talking barely at all- I can't imagine it would be enough to cause the problem.

Check everything with a straight edge, pulley to pulley to pulley. Check for damaged pulleys, sometimes you can get a dent in one that will roll the belt off. Also belt tension is critical. Look at parts manuals for any missing springs. We have an Exmark Navigator that was throwing belts like crazy. It turned out that the engine wasn't lined up with the rest of the pulleys.

Mule Drive Belts Tension Adjustment.
Self-tensioning idlers, adjust as follows:
a) Stop engine, wait for all moving parts to stop, and remove key.
b) Check to make sure the coils of the spring on the spring-loaded idler pulley
measures as listed below. See Figure 14.
Left Side Spring – 5 3/4” ± 1/8” (14.8 ± 0.3 cm)
Right Side Spring – 5 1/2” ± 1/8” (14.0 ± 0.3 cm)
c) If the spring does not have the correct measurement, loosen the nut holding the
adjustable idler pulley on each side so they can move up and down in the slot.
d) Relieve pressure on the spring-loaded idler pulleys.
e) Reposition the adjusting pulleys lower in the slot and tighten the nut.
f) Re-check to make sure the coils of the spring on the spring-loaded idler pulley
have the correct measurement. Repeat as necessary on both sides of the unit.

https://www.exmark.com/Service-And-Support/Manuals-Archive

 

[charford]

Thanks for the heads up. The pulleys do all look good- and we did adjust the idler arms as you suggest. I am very very cautiously optimistic at this point- I did notice there was a fairly significant amount of play in the idler arm bushings. We pulled them off and replaced the bearing sleeve and the bushings. We then re-adjusted to specs and put on new OEM belts- have put a couple hours on the machine at this point and it has not yet thrown a belt. I hope that has fixed the problem, although the dealer mechanic was skeptical that this would cause the problem. We will see!

 

[wambo101]

Hello,

I am new to this forumn, but at my last straw. I have an Exmark Lazer-Z- I think it is a 2002-2003. It is a Diesel, Model No. L-Z27DD724.

I bought this machine used last year and it ran great- but at the end of the season it busted a mule drive belt (it has 2) and also the clutch was smoked. We have a shop and are very mechanically included, but not experts. In any case we replaced the clutch and serviced the machine. This season started out and we blew another belt- thought maybe it was a bad batch, so we replaced them again and they broke again. At this point I started replacing damn near everything.

We replaced every single deck and idler pulley and bearing on the machine, and then it continued to throw belts.

We then tore the deck off and replaced the entire spindle assemblies, new blades, replaced the jack shaft bearings. We did not replace the jack shaft or triple pulley because they looked good. And the machine continued to throw belts.

Then we talked with a dealer and they mentioned maybe there was wear in the deck itself so we replaced the deck struts, pins, etc- re mounted, balanced, and measured the deck- I thought for sure that would get it as it tightened up the deck a great deal- also put on brand new belts for good measure- within an hour of mowing it threw another belt.

I have spent more in parts and belts than the machine is worth probably 3 times over at this point. Does anyone have any other ideas what could be causing this? The only thoughts I have at this point is that maybe the jack shaft is actually bent, but it really does not appear to be at all- or possibly the rear mule belt idler arm and spring? It doesn't seem like it would cause it, but there is a bit of play.

The dealer is at a loss, and basically has no further ideas. Where the deck mounts and pins are- there was a tad bit of wear on the holes on the deck (a bit egg shaped) but we are talking barely at all- I can't imagine it would be enough to cause the problem.

Honestly man i would look at trading it in and getting another, i know you can find cheap parts for your exmarks on www.redmowerparts.com