Bobcat 453

[kyhamoge]

Need help boys! There is a loud grinding & squealing/scraping noise coming from flywheel pulley area while engine idles! Of course, noise cannot be heard so much when running engine at full throttle. Could it be a pulley bearing? Also, lift arm action is slow...any possibility this is related? As always, I appreciate the good advice from fellow Bobcat owners & forum users!

 

[SkidRoe]

I would check the belt tensioner pulley. They can make a lot of noise when the bearing runs dry.
As far as slow lift arm action goes, it could be related, but the same belt drives everything, so the drive power should also be suffering.
Cheers - SR

 

[kyhamoge]

I would check the belt tensioner pulley. They can make a lot of noise when the bearing runs dry.
As far as slow lift arm action goes, it could be related, but the same belt drives everything, so the drive power should also be suffering.
Cheers - SR

Ok Skid Roe, thanks for the advice! I'm waiting on a service manual for the 453...any tricks to removing the pulley?...looks pretty straight forward. kyhamoge

 

[SkidRoe]

Ok Skid Roe, thanks for the advice! I'm waiting on a service manual for the 453...any tricks to removing the pulley?...looks pretty straight forward. kyhamoge

No real trick. It can be quite tight to the frame to slip the pulley out. Once you have the belt off, put a block under the tensioner lever to keep it from travelling forward.
HTH - SR

 

[kyhamoge]

No real trick. It can be quite tight to the frame to slip the pulley out. Once you have the belt off, put a block under the tensioner lever to keep it from travelling forward.
HTH - SR

Skid Roe - It looks like it is necessary to remove engine & pump assembly from loader first?

 

[SkidRoe]

Skid Roe - It looks like it is necessary to remove engine & pump assembly from loader first?

I didn't have to on my 440b to replace the pulley. Do you need to replace the entire idler assembly, or just the pulley? If you need to take out the entire assembly, then yes, you would have to pull the engine/pumps.

 

[kyhamoge]

I didn't have to on my 440b to replace the pulley. Do you need to replace the entire idler assembly, or just the pulley? If you need to take out the entire assembly, then yes, you would have to pull the engine/pumps.

SR - From what I can tell, just the tension pulley needs replacement...nothing left of the central spacer. The pulley is actually sitting cock-eyed because of the excessive wear. It just doesn't look like there is enough clearance between the mounting bolt on the arm and the frame to remove the pulley! It looks like there's barely enough room to remove the nut! For sure it's going to require a very long box wrench (ratcheting) to attempt. Anyway, I'm not sure if the 440 has the exact same setup or not. Can you indicate how much clearance you have between the mounting bolt/stud on the pulley arm and the machine's frame? As always, your help is MUCH appreciated!

 

[kyhamoge]

SR - From what I can tell, just the tension pulley needs replacement...nothing left of the central spacer. The pulley is actually sitting cock-eyed because of the excessive wear. It just doesn't look like there is enough clearance between the mounting bolt on the arm and the frame to remove the pulley! It looks like there's barely enough room to remove the nut! For sure it's going to require a very long box wrench (ratcheting) to attempt. Anyway, I'm not sure if the 440 has the exact same setup or not. Can you indicate how much clearance you have between the mounting bolt/stud on the pulley arm and the machine's frame? As always, your help is MUCH appreciated!

Engine does indeed need to be removed.

 

[SkidRoe]

Engine does indeed need to be removed.

With the arm rotated all the way towards the rear of the machine, there is just enough room to slip the pulley off of the bolt on a 440b.
It could be that a 453 has the tensioner shaft located closer to the pumps than a 440b, in which case, yes, you would have the frame in the way.
If you were to remove all of the bolts holding in the engine/pump group except the one by the gear pump, could you rotate the group enough in the machine to slip the pulley off?
If you do have to pull the engine and pumps out, take the opportunity to replace all of the hoses buried deep in the machine. I just had to do that on my 440b.
Cheers - SR

 

[kyhamoge]

With the arm rotated all the way towards the rear of the machine, there is just enough room to slip the pulley off of the bolt on a 440b.
It could be that a 453 has the tensioner shaft located closer to the pumps than a 440b, in which case, yes, you would have the frame in the way.
If you were to remove all of the bolts holding in the engine/pump group except the one by the gear pump, could you rotate the group enough in the machine to slip the pulley off?
If you do have to pull the engine and pumps out, take the opportunity to replace all of the hoses buried deep in the machine. I just had to do that on my 440b.
Cheers - SR

I wondered that myself - if the engine could be rotated or moved enough to remove the pulley...further investigation is necessary. If I do remove the engine, do you have any suggestions on HOW to get the engine out of the frame? Would an engine hoist be useful? I have a larger skid steer (S175) that I could use to lift out, if I can get some sort of harness or straps around it. As you can tell, I'm REALLY trying to avoid the inevitable I hear ya on the opportunity to replace all the old hoses, etc....makes sense. Thanks again SR for your time and advice!

 

[SkidRoe]

I wondered that myself - if the engine could be rotated or moved enough to remove the pulley...further investigation is necessary. If I do remove the engine, do you have any suggestions on HOW to get the engine out of the frame? Would an engine hoist be useful? I have a larger skid steer (S175) that I could use to lift out, if I can get some sort of harness or straps around it. As you can tell, I'm REALLY trying to avoid the inevitable I hear ya on the opportunity to replace all the old hoses, etc....makes sense. Thanks again SR for your time and advice!

With mine, I took the engine and pumps out separately. When I did the repower, I made a few changes so that the engine will come out more easily. Plus it is lighter chunks that you are working with. What the book says is to have a box, same height as the engine bay floor, behind the machine that you can slide the entire assembly out on to. I would think that a cherry picker would be useful, especially with the heavier diesel engine that you are working with. HTH - SR