Old Clark Transmission

[JMiller]

Hi, new to the forum. I have a 1976 Clark model C500-50LPG and the motor runs like a top but the transmission not so much. When you put it in forward, it revs up but either doesn't move or moves very slow and will not go uphill or move a load. Reverse is a little bit better but does the same thing. Sometimes when it doesnt move at all I can rev it up in neutral then slam it into gear and get it to move a bit. I have read some things about an inching valve but cant find it on my model. This model has two brake pedals and they pivot on a shaft that goes into the transmision, so I am guessing this has something to do with an inching or a safety mechanism. I am wondering what the two brake pedals do differently and also what are these strange shafts that go from the brake pedal into the transmision via a bearing (it kind of looks like a small axle shaft or something). Also what could this problem be? I checked the tranny fluid and it seems fine but if someone knows how to properly check the fluid on these machines please let me know!

Thanks, Jeremy

 

[Old Doug]

My clark has one pedal that is a brake and one that is the brake and puts it in neutral so you can rev it up to lift faster. The one wasnt comeing back and trans was sliping.

 

[BillG]

Is it a manual or powershift transmission? They were built both ways, if you have a clutch well it's obvious if you have an inching pedal (left one) then it's powershift. If it's manual then a clutch adjustment is in order. A powershift will require more troubleshooting. In this instance the left pedal will be connected to a master cylinder which in turn will be connected to an inching valve on the transmission. Posting a complete model and serial will be helpful.

 

[old-iron-habit]

Are you checking the tranny level when warmed up with the engine idling in neutral. That is what the manual says for the power shift in my Ranger skidder with a Clark transmission. Some old ones we had years ago were checked the same way. The level goes down quite a bit on the stick when running. God luck and keep us posted.

 

[JMiller]

It is not a manual so must be a powershift The serial number is: 355-127-1231
The model number is: 0500-50LP

 

[TD24]

Please shoot a picture of two looking DOWN on the trans so we can see what you are describing, ref the "two pedals and shaft".

 

[BillG]

That truck was originally sold to Dominion Glass and has an H200A transmission. If it were mine I would check the inching spool first and make sure it is not stuck. Also check the transmission fluid and check it for brake fluid smell, the inching could be leaking internally.

 

[JMiller]

Where can I find the inching spool? I will take pictures next time I am in the shop.