Anybody ever come across a defective belt?

[Dougcole]

I replaced the raw water pump belt on my 8KW Kohler genset a couple of months ago with a kohler oem belt. As usual it was so tight I had to take one of bolts out of the pump frame to slip it over the pulleys.


Ran the genset for about an hour, then checked it and found it had stretched quite a bit, enough that it was barely making adequate contact to turn the pump. I know new belt stretch is normal, so I was expecting some looseness, but it surprised me how much the belt had stretched.


Tightened it up, checked it again after two more hours of run time. Again, it was so loose it was barely making contact. And lots of belt dust, which I cleaned up.



Tightened it a third time, and a few hours later my genset shout down while throwing off an over heat code. The belt was so loose the water pump wasn't turning. More belt dust. At this point there wasn't any more room on the frame to tighten the belt enough for it to come tight.



Put my spare belt on (a gates) and ran the genset for 100 hours with no stretch, dust, or issues.


Defective?

 

[rslifkin]

I think I'd call that defective.

 

[O C Diver]

I replaced the raw water pump belt on my 8KW Kohler genset a couple of months ago with a kohler oem belt. As usual it was so tight I had to take one of bolts out of the pump frame to slip it over the pulleys.


Ran the genset for about an hour, then checked it and found it had stretched quite a bit, enough that it was barely making enough contact to turn the pump. I know new belt stretch is normal, so I was expecting some, but it surprised me how much it had stretched.


Tightened it up, checked it again two more hours of run time. Again, so loose it was barely making contact. And lots of belt dust, which I cleaned up.



Tightened it a third time, and a few hours later my genset shout down and was throwing off an over heat code. The belt was so loose the water pump wasn't turning. More belt dust. At this point there wasn't any more room on the frame to tighten the belt enough for it to come tight.



Put my spare belt on (a gates) and ran the genset for 100 hours with no stretch, dust, or issues.


Defective?

Going through that scenario, I would have considered removing the belt and measuring it after the second adjustment. I assume we're talking about a "V" belt as opposed to a serpentine. While I can remember some stretch in V belts, not to that extent. It seems odd to me that it could get that loose. I don't think of the alternator and water pump on a generator as having any significant load.

Ted

 

[soin2la]

Anybody ever come across a defective belt?

I thought this was about the one around your waist and I know mine keeps getting shorter.

 

[SteveK]

I thought this was about the one around your waist and I know mine keeps getting shorter.

good one

 

[tiltrider1]

I doubt the belt is stretching. More likely your pulley is wearing the edge of the belt and it’s slipping deeper into the pulley’s grove.

 

[Lepke]

If there was a lot of dust, the belt is wearing. It could be slipping on the engine or pump pulley but not making noise.

 

[Dougcole]

I doubt the belt is stretching. More likely your pulley is wearing the edge of the belt and it’s slipping deeper into the pulley’s grove.

The belt is three inches longer than it was when new, it didn't get that way by wearing into the pulley groove. Plus, it stretched that much in less than 12 hours of run time while the second belt I put on has basically not stretched at all and made no dust in over 100 hours of run time.

 

[Dougcole]

If there was a lot of dust, the belt is wearing. It could be slipping on the engine or pump pulley but not making noise.

I think it started making dust when it got so loose. The new belt I put on is not making any dust.


It's very strange.

 

[soin2la]

Have you had a conversation with Kohler?