Backhoe HW04X BH Hose Connection Problem

[RonMar]

In fact we'll be talking restrictors soon.

My HW-03 has restrictors in it on the boom swing circuit. The straight 18MM to ORFS adapters used where the hoses connect to the swing circuit working ports on the valve are only about 1/16" in diameter... All the other adapters are nearly 3/8"I.D. Found this when I turned the valve around during my reconfigure. Bucket curl moved real slow, and boom swing was so violent that it felt like it would roll the tractor over Even with restrictors, boom swing is a little faster than I would like. Been looking at perhaps adding lines and ports to the single acting swing cylinders to make them double acting, to nearly double the fluid volume needed to deliver a given ammount of boom swing...

Factory pump that came with mine has plenty of flow for my needs... I typically run the BH at around 1500 engine RPM.

 

[Smalljobs]

Ron...Tks.
Jinma informed me this AM they will send me the correct hose (after all my effort to eliminate their hose ). Looks like I'll have plenty of hoses and spare parts.

 

[RonMar]

Ron...Tks.
Jinma informed me this AM they will send me the correct hose (after all my effort to eliminate their hose ). Looks like I'll have plenty of hoses and spare parts.

Nothing wrong with spares Steve, you will use them eventually

 

[Smalljobs]

Things are humming along. Jinma advised me that several hoes were sent out with the wrong pump and hose. They already sent me the pump and the hose is on the way.

Meanwhile I'm staying on course to switch over to NPT/JIC for the pump pressure output line. This photo shows the barstock adapter to make the transition. It also shows the reusable hose end I plan to use. The pressure gage will be used during setup and later plugged. On the other end of the hose I already have a high quality adapter from Ronald at Ranch Hand and it will allow me to connect JIC directly to the BH valve assembly.

All the return filter components will arrive today. I picked up a 20 GPM filter with 10 micron cartridge. Bob Rooks...thanks for the link. It will be plumbed to 3/4" from filter outlet back to the tank. A 3/4" NPT coupling is welded to the tank inlet return fitting and the banjo is gone. Lastly, another one of Ronald's adapters will allow me to swap out the Chinese return line and connect my own JIC hoses directly from the BH valve assembly to the filter inlet.

 

[Smalljobs]

The tank return connection is done. A 3/4" coupling was cut at 2/3 to keep the center hex and it was welded on the tank where the banjo is normally connected. The banjo bolt is handy for holding the coupling in place during welding. Since the banjo bolt still fits, it might come in handy later.

Now I have a 3/4" line ready to pipe back to the 3/4 " filter outlet. Filter is 20GPM, 10 micron. Industrial rubber hose, hose barbs, etc. will be used to connect the filter outlet to the 3/4" NPT tank return connection.

 

[RonMar]

The tank return connection is done. A 3/4" coupling was cut at 2/3 to keep the center hex and it was welded on the tank where the banjo is normally connected. The banjo bolt is handy for holding the coupling in place during welding. Since the banjo bolt still fits, it might come in handy later.

Now I have a 3/4" line ready to pipe back to the 3/4 " filter outlet. Filter is 20GPM, 10 micron. Industrial rubber hose, hose barbs, etc. will be used to connect the filter outlet to the 3/4" NPT tank return connection.

That ought to work good. I initially did the same thing, and welded a street elbow over the banjo port to allow me to hook up a larger line from filter outlet to tank. Besides reducing the pressure spikes I was seeing at the filter, it also quieted the pump down. I think this was due to less air being entrained in the reservoir by the original narrow high velocity fluid stream caused by the small bore banjo bolt. The larger, slower velocity return stream into the tank puts less air bubbles into the reservoir fluid, so less air is sucked into the pump inlet.

Hydraulic fluid holds air bubbles very well. I had occasion to drain my BH reservoir the other day to add a longer pump suction line. I drained the system by disconnecting the pump output line where it connects to the valve inlet. I routed this line to a bucket and started up the tractor to let the pump move the fluid into the bucket. That line shooting straight stream into the fluid in the bucket put a ton of tiny air bubbles into the oil, that because of oil viscosity were very slow to work their way to the top...

Sounds like you are about ready to put her to work

 

[Smalljobs]

We have "Liftoff" ! Today I swapped out the Chinese high pressure and return lines with my own hoses made with reusable fittings. It began with high quality adapters from Ronald at Jinma Dealer, Wood Chipper , Compact Jinma Tractors

These little adapter fittings are high quality, packaged well, and really made my life easier. Pictures below show the high pressure inlet side of the valve assembly but I did the same for the return. The picture scale makes them look smaller than the original Chinese hoses but, in fact, the ID is slightly larger.

The inline return filter-directly-to tank is in.

Finally, I backed the tractor with the subframe up close enough to mount the pump, connect hoses, etc. I now have maybe 4 bolts holding the hoe to the subframe - enough to move it off the metal pan of the angle iron crate. All systems are go. So far, no leaks and no real problems except for an oversize O-ring on the suction connection. I snipped it to length and installed it anyway. Later, I'll replace it. For now, I just want to get it up and running and debug any remaining surprises.

Over the next few days, I'll check and adjust the relief valve, secure the filter line, retighten all bolts, make a bracket to hold the return filter, etc.

 

[Smalljobs]

We had 12" snow for Halloween but BH is done! I might use my extra remotes, front and rear, to add a thumb later.

 

[RonMar]

Hey, you may have already figured this out, but when the BH is installed, be carefull when flipping the ROPS down like you have to, to say get in thru a standard garage door. When I was installing my BH initially, I had to lower the ROPS to get it out of the garage. The ROPS, and top, when flipped down to the rear, pushed the BH controls tothe rear and pinned my BH boom down controls. The boom went down, the tractor rear went up and really pinned the controls as the tractor rear rose into the air... Got the engine shut down pretty fast, otherwise it could have been real ugly... Had to crack a hose fitting to let the boom lower the tractor back down.

 

[Rich Waugh]

Good thing you have quick reaction time, Ron!:thumbsup: