Topkick dump - adding hydraulic fluid

[csthompson12]

Hello, my 2000 Chevy topkick dump truck has the large lift cylinder that also acts as the hydraulic fluid reservoir.. There is no separate reservoir.
I recently blew a hose, and need to add hydraulic fluid. What is the best procedure, just prop the box up, and remove the plug at the top of the cylinder and fill it to the top? I've never had to add fluid before...

 

[Delmer]

gonna need a picture. Chevy didn't make a dump cylinder, so anybody would be guessing what you have. Most likely you can add fluid without lifting the box. Might have to add, then lift and lower, then add some more.

 

[CM1995]

Might have to add, then lift and lower, then add some more.

Well if he can't access the top of the cylinder with the bed down, now is a good time to make the gas axe modification.

Whatever you do or anyone else does reading this thread the FIRST thing you do is support the bed while it is in the air with either a timber or steel member strong enough to hold the bed. Some dump beds have supports on the frame and some don't.

 

[csthompson12]

This isn't mine, but it's identical.

 

[CM1995]

Well scratch my gas axe recommendation I thought it was a vertical cylinder.

 

[1466IH]

There has to be a reservoir somewhere. Even if they used the rod end as the tank it would not hold enough oil to fill the barrel and there is no hose to get the oil to that end of the cylinder. Does truck have a pto or an electric pump?

 

[Delmer]

I'd still try to fill it flat. Looks like it would be tight, but doable with a hose and pump. If you fill it with the bed up, not only is it somewhat dangerous, it would be easy to overfill and if there's no vent it could pop something going down.

 

[csthompson12]

I'd still try to fill it flat. Looks like it would be tight, but doable with a hose and pump. If you fill it with the bed up, not only is it somewhat dangerous, it would be easy to overfill and if there's no vent it could pop something going down.

Ill give that a try tomorrow .. I just figured there would be no way to get in there with the bed down, but maybe I can get my hand up in there.

 

[1466IH]

I really do not think adding oil to the cylinder is a good idea

 

[Delmer]

Why not? that's a common design to use the cylinder for the tank. Hopefully csthompson knows how the system works, and can see the plumbing that makes sense in person. Worst that will happen is the lift doesn't go up, or spills some oil. On the other hand, filling it full while extended, and then leaving weight on the cylinder, could cause the rod to intensify pressure and pop something.

 

[1466IH]

I see no hoses at the rod end of the cylinder so how does oil flow get from there to the pump? I have never seen a system that uses the cylinder as a tank. How would it hold enough oil in the rod end to fill the piston end at full stroke? I know most of those one way cylinders have a vent on the rod side to let air escape and they have a hard time letting oil past. I just do not want to see him break something or injure himself when the vent wont let oil out and the pump blows the rod guide apart. More pictures would be the best to give him more specific guidance

 

[Delmer]

I guess he described his system in a way that made sense to me, so I'll take him at his word that he's looked it over.

 

[Willie B]

That's a new one on me! Mine has two double telescopic cylinders. Like yours, one hose to each cylinder. It fills a ten gallon reservoir when down & above the piston (rod side) fills with air when down.