Power-Beyond Kit, leftover Hydraulic Banjo Lines?

[tomrscott]

JerryG,

I have to take issue with part of what you say.

First "Both" is just not correct. There is absolutely more cross-sectional area through every part of the banjo (see the drawing I've posted and do the calculations if you are skeptical) than through the tubing it connects.

Second, strictly speaking splitting the flow should not make any difference and the difference between four small 90 degree bends and one large 90 degree bend just doesn't seem like that big a deal. I would sure like to see any source for actual data to back this up.

If you are just speaking from theoretical perspective, but have no evidence to nail down the objective magnitude of the effect, then my gut tells me the difference between a standard fitting and a banjo is just insignificant at these rates of flow and pressures, whether driving a motor or a cylinder.

Look at the internals of a spool valve, it has lots of flow paths that are every bit as convoluted as a banjo fitting.

I would truly be fascinated to see any real data to quantify the effects, but I'm not aware of it and I am not familiar enough with fluid dynamics to do the analysis. I work with some mechanical engineers who are plenty expert enough to easily do this analysis and may have a talk with them.

Again, I want to reiterate that I am not trying to be difficult but just want to understand the perspective from which you speak. You may well know better than I, but some of what you say is I think incorrect, and in the absence of data, I remain somewhat skeptical. Happy to be corrected if I am mistaken. /forums/images/graemlins/smirk.gif

 

[JerryG]

Tom,
The higher the pressure and the higher the flow the more a banjo will effect the performance. Yes, you can get around the problem and still use a banjo, but you would have to increase the size of the banjo. Like I has said before, given the standard use of compact tractors with small cylinders, low flow and no high speed hydraulic motors, no one here should have any problem using banjos like in use on your tractor. But, If I was putting together a new system, I personally would want to make the system as efficient as possible.

 

[tomrscott]

Rockyridgefarm,

I don't think there are any banjos on the 43xx tractors.

I stopped by two large JD dealers today, and looked at a few tractors to see which ones used banjos. I think most of the 6xx 7xx, 8xx, 9xx use the same SAE-8 (3/4"). From what I could see on the 43xx, it looks like it uses conventional fittings. The 41xx I saw looked like it had SAE-6 Banjos on the FEL valve.

I asked the dealers if they had any scrap lines, but they couldn't remember the last time they had installed a power-beyond, and they had never heard of a line failing. It would be a long shot to get any lines from them.

Thanks for looking though! /forums/images/graemlins/smirk.gif

 

[JB4310]

tomrscott,
Your right, I double checked, the 4310 has the straight fittings, could have sworn I'd seen those banjos on the line I got back after the power beyond was installed, must have been somewhere else, will keep an eye out.
John

 

[tomrscott]

Last call for anyone with any left-over banjo fittings they don't need, before I spend a few hours at the lathe to fabricate the last one.

MANY THANKS to Brian M. Lekki and James Woods for the care packages they sent; some left-over hollow bolts from Brian and a line with one banjo and one bolt from Jim. MUCH APPRECIATED! Hope I can return a favor some day.

The bolts will save me making them from standard bolts.

With the dual banjo I made on the lathe (see the thread over in the "Build-It-Yourself" section about "SAE-8 Banjo Fitting Autocad"), and the one that Jim sent, I just need one more standard banjo if I can re-use the ones on the lines I am replacing. That assumes I can un-braze them without any trouble, which shouldn't be a problem, but I've never tried to do that before. Should be about like un-soldering copper pipe, only hotter.

Any more banjos out there collecting dust? I will pay something reasonable if you've got one you can spare.

I can make them on the lathe, but it just takes a lot of time.

Thanks! /forums/images/graemlins/smirk.gif