Hooking up an old backhoe for the first time (in a long time)

[Gudor]

So I just picked up the following project/headache, it is an old Brantly backhoe (says model 330 MT, but I cannot find a thing on that model #) - looks to be pretty much the same thing as a Kubota 619 or 629 backhoe made for the B6000 & B 7100. It needs a fair amount of attention, but I first thought I should hook up the hydraulics to see how much it leaks - not if, but how much . It is old and I wouldn't be surprised if it hasn't seen action in 20 + years.

Originally it probably had a PTO pump, but no longer, and I don't have one. What I do have is an aftermarket diverter valve (I think it may be called a selector valve) on the rear of my tractor - see pic.



There is also a return line for the hydraulics on the other rear fender.

Any thoughts on the best way to test the BH (I am simply wanting to see cylinders extend/retract - absolutely no digging - it has no bucket). The best way means economical as well (so I cannot purchase a PTO pump/etc. to test).

Here is my thought, please comment on or suggest a different way (if you suggest a different way, please let me know if it is because something is 'wrong' with my idea, or if it is just a different way):

• I had some hoses made up to connect to my tractor through the diverter valve.
• There is a reservoir on the BH that I was going to bypass and connect the lines directly to the BH valve. (one less thing to fill up or pick up contaminants from)
• I was then going to switch the dirverter to the BH (with the return going into a bucket, not my tractor...once again, contaminants)
• Just cycle through each cylinder to see how they respond

Is it okay to just have the return going to a bucket? I would be at idle speed and of course have to continually check the fluid level of my tractor (diverter should help so I don't have to turn the tractor off to stop the flow to the BH). I am terrified of getting contaminants in my tractor, so I figure I would lose some $$$ in fluid, which I am okay with. I thought about getting an inline filter for the return, but I wanted to make sure the BH was going to work before purchasing that.

While I was taking off the hose to the reservoir, about 2 cups of red fluid (auto trans/brake/???) did pour out - it was clean at least. One more reason to discharge to a bucket. I think I have UDT fluid in my B2150, so I was planning on just using that.

Do I need to 'bleed' the cylinders or anything like that, or should cycling through take care of any issues?

Lastly, what should I expect when I cycle through a cylinder? Apart from it extending (I hope), should they leak a little (even if they are fine); meaning could the seals could improve with use? Other things to watch for?

If it checks out, I could then start to tackle things like finding/fabricating a bucket among other things...

Here is a picture of the BH



Thank you for any advice/insights you can give.

 

[J_J]

Yes, you can do as you have planned.

If your tractor can pumping 2 GPM at idle, in 30 sec, you will flow one gal of fluid through the BH.

You could install a 3000 psi hyd gage in a tee in the IN port of the BH valve and see some pressure as you check out the cyl.

The air will purge itself as you operate the cyl.

 

[Gudor]

Thank you for the boost of confidence in my plan J.J. Would I want a liquid filled or dry gauge? Surplus Center has one liquid 3000 psi gauge but many options for dry - could you please suggest one? Are dry gauges for dry applications (like air) and liquid filled for my situation? I will definitely install one if the BH is worth fixing. Also, could you fill me in on the simplest, most economical way to tee in the gauge (I think I remember reading that many plumbing fittings cannot take the PSI we need)? I am guessing the Kubota dealer is not the best option for the plumbing parts.

Thanks again.

 

[L355SS]

You won't see many seal leaks if you have an open line to a bucket. You need to 'work' each cylinder to be able to see any leaking seals. You may want to secure that hose to the bucket as 2000psi will have quite a forceful flow.
Dennis

Yes, you can do as you have planned.

If your tractor can pumping 2 GPM at idle, in 30 sec, you will flow one gal of fluid through the BH.

You could install a 3000 psi hyd gage in a tee in the IN port of the BH valve and see some pressure as you check out the cyl.

The air will purge itself as you operate the cyl.

 

[Gudor]

You won't see many seal leaks if you have an open line to a bucket. You need to 'work' each cylinder to be able to see any leaking seals. You may want to secure that hose to the bucket as 2000psi will have quite a forceful flow.
Dennis

I guess it makes sense I will have to have a 'load' against the cylinder to really test them. So if it leaks at this stage, then I will probably need to do some work on the cylinders...but I shouldn't have any psi build up on the return line (unless I 'stopped' the flow at the end of the line), right?

 

[J_J]

There should be no back pressure on the hose in the bucket ,

As far as the hyd gage, it should be a liquid filled as the one you found at Surplus.

If you want to use it full time, you can permanently mount the gage in the IN port of the FEL valve using a tee , or use the gage as a portable test rig, and plug it anywhere you want to test.

Here are some hyd gage test sets that some of the TBN people have built.

.

 

[J_J]

Here is a bucket kit from Metkit.

I have purchased some buckets from Ebay.

MetKit Corp - Home Page

Select New Products left side of page.


800 series rounded bucket.

 

[Gudor]

Here is a bucket kit from Metkit.

I have purchased some buckets from Ebay.

MetKit Corp - Home Page

Select New Products left side of page.

800 series rounded bucket.

That is a neat site J.J., thanks for letting me know about it. Their prices seem reasonable, and with the surplus site that should give me options...dealership is pretty pricey. I gotta go back as the female fitting they gave me was the wrong size (had a picture and model of the quick connect...this time I am taking it off the tractor and bringing it with me). I hope to load the cylinders in the next couple of days.

 

[dfkrug]

Do I need to 'bleed' the cylinders or anything like that,
or should cycling through take care of any issues?

I know it has been a couple of weeks, but in case you have not done this yet....

What I do with new or used hoe attachments is I drain out as much of the fluid I can
before connecting to my tractor. I do this by fully extending and contracting
each cylinder by manually moving the boom, dipper, outriggers with the OUT hose in a bucket.
This may require a helper to operate the levers while you do this. If you can't fully
extend the cylinder, then pull one pin.

Before you do that, clean each exposed rod with steel wool so no dirt or rust
will damage the gland seals. If there is much rust on the rods, I would
repair the cylinder(s) first.

Even new hoes are often full of crappy cheap straight hyd oil, rather than THF,
which your tractor uses. I am not a fan of PTO pump systems, which often
have more contaminants in the oil because the system is not sealed.

Once you have done that, you can flush out the tiny amounts of oil remaining
using the tractor hyd system as you mention, but you can only operate
it a few seconds before you run out of that $10/gallon UDT.

 

[don45640]

When I bought mine in `93, I had a friend of mine, an excellent equipment operator and maintenance guy, go out to my house and look it over. He checked it out, and said 'run it' .LOL! He also said `you ain't gonna hurt THAT machine!' But yes,I went thru the service manual and did all the lube and filter changeouts before working it hard.Change the anti-freeze,too.....unless you KNOW it ain't old. don-ohio ^)