951-c joint drive pucks

[Papa Smurf]

hello everyone , I'm the new guy on the forum. Was hoping to get advice on replacing the flexible coupling drive pucks on my 951-c track loader. Thanks.

 

[Nige]

The more access you can get the better. You'll probably need the floor up and the belly guards down (be careful if they haven't been down for a while. They will be full of mud and HEAVY.)

While you are replacing them you should really check the run-out between the two flanges using a dial indicator. The closer you get the flanges to being parallel the better the replacements will live. The engine can be shimmed both front and rear in order to get the two flanges aligned.

 

[DMiller]

The more access you can get the better. You'll probably need the floor up and the belly guards down (be careful if they haven't been down for a while. They will be full of mud and HEAVY.)

While you are replacing them you should really check the run-out between the two flanges using a dial indicator. The closer you get the flanges to being parallel the better the replacements will live. The engine can be shimmed both front and rear in order to get the two flanges aligned.

Usually the cause along with age as to these failing, mounts cushions sag over time.

 

[Nige]

Usually the cause along with age as to these failing, mounts cushions sag over time.

Yup. A set of replacement engine mounts may also be on the cards in addition to the drive pucks.

 

[Tags]

Not knowing anything about it other than what I've read on here, but since the drive pucks keep everything aligned and they rely on the engine mounts being solid, wouldn't it be good practice to just replace them if you're replacing the drive pucks?

 

[Papa Smurf]

Thanks for replying. Let me give more info. The guy I bought machine from had just had the engine out and replaced the head , along with other work done. He is a reputable mechanic and does good work. He is mechanic by trade and buys equipment needing repairs and resells for profit. Do those pucks fail with age? Could something else have caused the failure? Just before they went out the machine was having a slight hesitation when put into reverse.

 

[Nige]

If he had the engine out the likelihood is that he possibly did not check the alignment/runout of the two flanges in between which the pucks mount during the engine refitting process. Also removing the engine would have been a perfect opportunity to install new pucks.

Possibly the shims/spacers that are available to install under the engine mounts to assist with obtaining the correct alignment between the flanges were omitted during the engine reinstall or installed in the wrong places.

 

[Papa Smurf]

Yes sir Mr. Nige, after checking all the paperwork the previous owner gave me, I found receipts for 4 new pucks, or driveline bushings , as he called them. I've only put about 10 hrs on machine since purchase. It sounds like you are correct about not being in alignment. That is probably why they failed already. Thanks for the info, very helpful. How much is involved in getting everything into alignment with installation of new pucks? I've got a manual that describes the process, but it is helpful to hear tips from someone who has done the procedure.

 

[fest777]

you need a dial indicator with a 3/8" shaft attached, then clamp the shaft too the input shaft of trans with hose clamp with flange off, then clean flywheel real good knock any high spots down, then you will rotate input with dial indicator touching face of flywheel, try to get face as close to 0 as possible , face run out has to be adjusted whit shims in front mounts, also check trunion behind front dampner ,alot of times the rear mount hole get oblong and you may need too shift to one side or the other, cat recomends using dowel pins to stop side movement, or try drilling next oversize. next to the outer flywheel run out run the indicator on the outer edge of flywheel , you will dial this in with shims at the rear mounts, use hardened washers like .030, ,060,.080 and so on, also before or after starting rotate flywheel with pucks in with slight torque on bolts put your hand on rubber side of puck where bolts go in see if its pulling as its rotated you will feel on the edge on pucks its about a 1/2 day procedure take your time do not get in a hurry or it will only last a few hours if not in aligned good luck i just did mine about 3 months ago

 

[Papa Smurf]

Yep, sounds good. Gonna have a go at the alignment and repair. Thanks .

 

[Dave Neubert]

I'm in Monroe if you need someone to look at it Dave's Diesel 704-361-4231