3400 Ford Back-Hoe problems

I recently install a used 10" back-hoe on my 3400 Ford. I completely flushed all the hydraulics and fluid came out real clean.The swing arms worked great. Now they are kind of stuck and excess chain on each side. Do I need to bleed something. I'll try to post picture.s
 
Is this a Ford hoe? If so there is a box on X brace thats next to tractor that has bleed screws on it. Dont remember procedure. Im not much help but may this helps.
 
Presumably the 750 hoe (not to be confused with a much later 750 machine) as the 10 foot version of the 750/753/755 10'/13'/15' hoe series that would be normal for mounting on a 3400 (well, not the 755 on a 3400, at least per the hoe manuals, but anyway...)

The swing cylinders are single-acting - they only pull.

If you ground the hoe and pull (gently) with the swing lever that should take up any slack. This might help. http://www.yesterdaystractors.com/cgi-bin/viewit.cgi?bd=ford&th=37434

If the other side is being pushed out, you may have a seal leak. In the older version of the hoe plumbing the backside of the cylinders had an air vent - in the later version (or if retrofitted - I did mine with $5 worth of hardware-store parts), the air vent (and source of dirt) was replaced with a plastic tube connecting the back of both cylinders. It should only have (clean) air in it. If yours has oil, that would mean a failed seal on at least one of the swing cylinders.

It is possible that some malfunction of the "combination valve" might also impact this, but I don't know for sure that it would - I just know that it is in that circuit and adds an additional variable, since the control lever does not actuate the cylinders directly..

I consider some slop in the swing "normal" but if you really have "loose chain" something is up. Do know that the chain is purely a tension member - it's pinned to the cylinder and pinned to the knuckle(swing post), without a tooth anywhere.

Add-edit: The combination valve (7704205) is what's on the X brace. But there is no mention of bleeding ANYTHING in the hoe assembly manual. Bubbles should (as I understand it) go out of the system and into the return with normal fluid flow as you actuate the cylinders, and be vented from the hydraulic power source at the vent before the pump suction (nose tank on a 4500, loader pump system on a 3400, at a guess).
 
What Ecnerwal said. See if the air vents on the back of the swing cylinders were replaced with plugs.
 
TO Ecnerwal:

That was the problem. I took rubber hose off from each end of swing arms and when swinging the backhoe a lot of fluid came out and then slowed down. I hitch up the rubber tubing and move backhoe back and forth about 15 times and same problem. Chain real loose. Both piston all the way out. Discount rubber hose again and relived pressure and swing arms worked good about 15 times and same problem. Will take swing pistons out and put new packings in. We have a company called Seals Unlimited that have just about all seal seals made. usually about 25% cost of Ford. I replaced all the seals last winter in the main control valves and cost less than $15. thanks again.
 
You are welcome. I may have to look that company up.

There's a load of stuff I don't know, but I know a little about these hoes. Now, grab a nail, a rag and a grease gun and see if you can get any grease in the fitting on the bottom end of the bottom pin on the swing post, after you use the nail to dig the packed dirt out of it so you can actually find a zerk...unless it's a very abnormally well-maintained machine.

If it's not obvious (it may be if you just mounted it) the swing cylinders will be much easier to work on if you dismount the hoe. Mounting and dismounting the hoe (Ford manual style) is done with the hoe picking itself on and off the tractor - you disconnect the hoe hoses after it's parked and blocked up, then drive the tractor away, and back the tractor up to it, connect the hoses, and then mount it using it's own hydraulics. The high-pressure hoses loop - one on the tractor to feed the loader, and one on the hoe to keep both sides clean/sealed. The low pressure hose screws to a fitting under the deck - that fitting is supposed to have the cap for the corresponding pipe on the tractor stored on it.
 

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