TYM BY85 Backhoe Boom Speed

[halfBaked2024]

Has anyone installed flow restrictors on this model backhoe to slow the boom down? I’m trying to figure out if it matters where in the flow path I install them and what fitting types (JIC?) I need to source.

 

[ptsg]

There are two types of flow restrictors: The two way, that adjusts the flow in both directions and the one way that adjusts the flow in one direction but lets full flow in the opposite direction.

Do you want to adjust the speed the boom drops or the speed the boom raises? Or both?

If you want both, I'll suggesting installing two one way adjustable flow restrictors, so you can set different speeds for raise and lower. If you just want to the speed the boom lowers, you just need a one way flow restrictor on the rod side of the cylinder.

The fittings will most likely be JIS, but definitely confirm that.

 

[halfBaked2024]

I was thinking I’d put restrictors on each of the two incoming lines for maximum tuning ability (I’d start with 1/32” and drill them out until it was where I liked it. The thing drops like a rock, but the raising speed didn’t seem as bad.

I found some 1/4” restrictors that I could put on the rod and cylinder sides of the cylinder, but according to the parts diagram, there is one 3/4” and two 9/16” fitting locations along each of the flow paths on the attachment. Another thing I could do is put valves in the tractor flow paths like they have on the big boys.

A concern I have is heating of the fluid as it goes through the restrictors, but I may be overthinking it.

 

[Racer4]

What rpm are you running at that’s causing your boom to be too fast?

 

[halfBaked2024]

Near idle - 1500 rpm. And, I’m ginger on the controls, so… not that either. Here’s an experienced operator with the same setup.

 

[kneedeep]

Most modern small BH have a boom speed control to do that.