clark 721

[gonecrazyi]

I just picked up a Clark 721 bobcat with a duetz diesel. It sat for awhile and needs some tires. But it fires up and runs great. I ran it for a few hours after buying it (checked all the fluids first) it runs great but ended up breeding 4 or 5 lines and some one kinked one of the cooler lines which I also redid. I have a couple of issues. I got all the lines taken care of so far but I am leaking fluid out of the hydraulic return tanks on the side of the machine. They actually both leak really bad. I'm not sure exactly where to get them or if there is an easier fix. 2nd. When the machine is run for awhile the left side gets a little jerky but stops of you let off or give it full open. 3rd. I think I may need to do the valve guides. I have a lot of blow by to where it drips a little when run for a few hours. Does any one have a manual for one of these as well? Thanks for any help

 

[gonecrazyi]

Anybody?

 

[Tazza]

Anybody?

I didn't reply as i have never seen one of these machines in person. The tank that is leaking, is it rusted through?
The blow-by can just be ring wear, the actual guides i assume are just seals top and bottom that are allowing drips.
I wonder if this machine has a suction line filter, the early machines did and when plugged, they woul run well at first, then start to loose power and just scream when you tried to move with very little power.

 

[OldMachinist]

I didn't reply as i have never seen one of these machines in person. The tank that is leaking, is it rusted through?
The blow-by can just be ring wear, the actual guides i assume are just seals top and bottom that are allowing drips.
I wonder if this machine has a suction line filter, the early machines did and when plugged, they woul run well at first, then start to loose power and just scream when you tried to move with very little power.

Are the tank leaks coming from the side plates? You said it sat for a while, did you drain any water build up out of the tanks? There are drain plugs on both sides to do that.

 

[HanSolo]

Anybody?

Another source of leaks are the seals on the axles. The M700 I owned started leaking a little on a couple and then greater as I used it more. While I had the machine on blocks I tightened up the four securing nuts on each axle to 100 fp and got the leaks to stop.

 

[gonecrazyi]

Another source of leaks are the seals on the axles. The M700 I owned started leaking a little on a couple and then greater as I used it more. While I had the machine on blocks I tightened up the four securing nuts on each axle to 100 fp and got the leaks to stop.

I didn't drain the fluid at those ports. But I will. Most of the fluid leaked out when I replaces the kinked cooler line. The vents that are leaking on mine are visible when you open the back access door and look to the left and right sides at the tops of the tanks. The fluid had a little water in it but I got most of it out when it drained out the return. Other than those vents leaks and a lot of blowby, it runs and starts great.