Servicing hyd on 71 Chevy dump truck

[Wis Bang]

It wouldn't be the first small dump body w/ a hole in the floor!

You should be able to get seals & hoses to stop the leaks and fix it right. What will you do when the hose or pump seal pops while lifting a load? Even if you could get to the offending part, you would need to shovel the stuff out enough to reach the hole which will be close to the center of the bed & therefore under the most of the load...b/4 you could add oil.

I've seen flat steel supports, one end bolted to the body floor supports & pinned at the other. Pull the pins & raising the body makes the free end swing out become a support once it is vertical & you let the weight down some so the bed is supported. Add a few 4x4 props for insurance & go to work...

I'd fix the leaks; pump seals & hoses are easy to replace & any good hydraulic shop should be able to find/make parts if the cylinder is leaking...Like Eddie said it could be as simple as the rings not being staggered...

Anything you do to it will add to it's eventual re-sale. Even if the chassis is shot; the dump body will have value.

 

[AlanB]

Funny you said that Wis bang as that was the discussion, I bought a dump bed for $900, just happened to come attached to a 71 Chevy Chassis

Might look at it this weekend again, have to see what SWMBO has in mind, probably servicing mowers.

 

[Dirthog]

you can cut all the holes you want in the bed but you still have to fill it with the bed up and they will use some oil they are a single acting cyl there will be some seepege past the packing and then it blows out the breather ran one of those for years. Take a piece of 2" steel pipe and make a prop for the bed it does not take much to hold it up. first time you have something stuck in the back of the bed you will see how hard it is to get it to lower you will then reliese all the more it takes to keep it up. The mack I have only has a 1-1/2 pipe on each side from the factory.

 

[EddieWalker]

When I grease or work on mine, I put a 2x6 on each corner to keep it in the upright position. I just wedge it between the dirt, behind the cab and into one of the cross beams on the bottom of the bed. Simple, cheap and effective.

Eddie

 

[sandman2234]

I drove a International with a hydraulic lift fifth wheel on it, that was set up like your dump. No tank, just the cylinder for a reservoir. We filled it from the top side of the cylinder, with the cylinder retracted. I think I still have one of those pumps out in the garage. Cutting a hole in the bed is easy enough, as long as you double check the location so you don't have to cut it twice. Doing it with the bed up and blocked is easy enough, but tends to overfill the cylinder/system.
David from jax

 

[Dirthog]

The old chevy dad had you had to fill it with the bed up! It would not raise the whole way and you knew it was time to add oil never leaked a lot but if you would run it steady all day you might have to add a quart or so to make it raise clean up most of the time we never ran it to hall more that a couple of loads a day so it was no big deal.

 

[AlanB]

Dirthog, why would I have to fill it with the bed up? (After I had a hole that is.)

Thanks

 

[Diamondpilot]

Told the guy who has the Ford Dump Truck about this discussion yesterday and he also said you had to fill it with the bed up. He said he has used a chain high in a tree then pull the truck forward to lift it before.

I am guessing the reason for the bed being up is the position of the piston in the cylinder with it down. You can not get enough fluid in the cylinder. He also said his truck and bed have a pocket to place a 4x4 to prop the bed up.

Chris

 

[Dirthog]

because when the bed is down you can not fill it to the proper level in fact if you take the plug out with the bed down you will lose oil and the bed will not raise!

 

[Wis Bang]

Filling the cylinder when the piston is collapsed [body down] should give enough oil to get the body up. The housing holds all of the oil not in the plumbing/pump when the bed is down and the pump simply transfers this to push the piston out. If you overfill this resivour w/ the body raised, where will the excess oil go when you lower the body? This is a single action system [power up only] so the piston has to drain back into the housing to let the body down. Too much oil will prevent the piston from retracting into the cylinder unless there is enough weight to blow out a leaking hose/pump seal.

Fix it properly and don't fill the housing...