Bobcat 763 Help

oldnslo · Mar 12, 2018

Are you talking about the jam nut that locks the fitting into the pump? If yes I would be very surprised if left hand thread. This nut is just to lock the fitting at the desired orientation and should not be super tight. Possible someone used locktite but they shouldn稚 on that style fitting. Try an impact but don稚 go to crazy. Can you put a vice grip on the shank and keep some torque on the nut while using the impact. I have had some success in breaking stubborn nuts and bolts loose this way.

Good luck and remember

Stubbornness will overcome most obstacles ;-)

Hilbilly · Mar 12, 2018

I didn't realize that was a jam nut and tried turning the bend counterclockwise and when that didn't work I tried turning the jam nut (but not holding the shank / bend). Earlier I tried using the impact, on low setting on the jam nut with no luck. I will give the impact another go tomorrow, while holding the shank / bend. I think that could be the solution and thanks again for helping out.

Sometimes my stubbornness gets me into more trouble than if I'd given up. In this case I'm close to giving up and taking it to the dealer but that will be another PITA. I would have to dig out the trailer that is buried under 2 ft of snow, go to town to get trailer insurance (30 minute trip each way), make sure the brakes are working since the trailer hasn't been used in a few years, load the SS and take it into the city which is 1 hr and 15 minutes away. There's 2 days shot and 2 trips to the city by the time they do the work and I get to pick it up. Sometimes living in the country has it downside.

oldnslo · Mar 13, 2018

Don稚 worry about holding the elbow. If it turns with the nut great. Take the fitting out of the pump and worry about getting the nut loose.

And yes one of my best friends claims that stubbornness will always overcome common sense

There have been times when I wished I could have proven him wrong

laurencen · Mar 13, 2018

the nut is a jamb nut, it threads on the fitting, sometimes it helps to turn the nut with the fitting to get it to loosen,

Hilbilly · Mar 13, 2018

laurencen said:
the nut is a jamb nut, it threads on the fitting, sometimes it helps to turn the nut with the fitting to get it to loosen,

Maybe that's the ticket. I'd need some help to do that or I would need to grow another arm.:laughing: If I can't get it with the impact I will have to wait until my son in law has a few minutes to give me a hand but that could be a while.

Hilbilly · Mar 13, 2018

I give up. I tried it one more time after a further soak with penetrating fluid and the impact as high as I dare but still no movement. The torque was enough to deform the 3/8" thick mild steel crow foot wrench I made and I don't want to damage the jam nut any further. So I will have to make an appointment with the dealer to get this done. Maybe after most of the snow is gone so I don't have as much work to get the trailer out.

laurencen · Mar 13, 2018

Hilbilly, never had one this tight, both the nut and fitting turn anti clockwise, has some tight and usually having a wrench on both nut and fitting does the trick, you have little movement but all it needs is a few degrees to loosen it up

if the dealer is decent they will advise, my dealer has borrowed tools overnight

laurencen · Mar 13, 2018

is the leak coming from the jamb nut and block, there is a odd washer with a O ring, your picture shows the area clean, I have no idea how the ring would leak with the nut that tight

Hilbilly · Mar 13, 2018

laurencen, anti clockwise it the direction I am trying but no success. I'm not able to get a wrench on the bend plus the crow foot wrench on the jam nut at the same time. The crow foot bolt interferes with where the open end wrench wants to be. Even if I could get both wrenches on at the same time I wouldn't be able to apply enough pressure to both wrenches at the same time. It's such an awkward place to get into.

I cleaned off the area where the leak was so I could see where it started to come out when running. It appears to be coming from either between the jamb nut and the bend or from the between the jam nut and the pump housing on the bottom. I didn't see it until I used a mirror to look at it. There is a very definite leak here. When I run the SS and use the hydraulics, the leak first starts as a slow drip and then escalates into a fast drip followed by intermittent slow streams (like a run of drips that are attached) then back to a few drips and back to the stream. It is hard to believe there could be a leak there when these things are so tight but there is.

Based on your suggestion I think I'll send an email to the Bobcat dealer showing them a pic of the fitting and see what they suggest. The awesome parts guy is back and he is very helpful.

laurencen · Mar 13, 2018

thats stupid tight, usually the nuts are just tight enough to stop the elbow from turning, wonder if it was a issue for the last owner and they used locktite or similar to seal it up

Hilbilly · Mar 13, 2018

laurencen said:
thats stupid tight, usually the nuts are just tight enough to stop the elbow from turning, wonder if it was a issue for the last owner and they used locktite or similar to seal it up

I wouldn't doubt it. I wonder if they used red locktite. I did try using a heat gun on the pump this morning but after about 3 minutes of applying heat there was no noticeable change so I gave up, thinking it would take forever to heat up all the metal and fluids that are in or attached to the pump. Maybe I should give that another go for a longer time. Hopefully they didn't use something permanent and then sell it before the problem returned.

laurencen · Mar 13, 2018

not sure a heat gun will do much, any way you look at it they nut and fitting needs to come off, its a possibility the nut was tightened so much it fractured the elbow, the issue with the way you used the impact its not fully acting on the nut as it needs to, can you get a hammer wrench in? they are heavy short wrenches designed to be hit with a hammer, with the pipe off the elbow you mag be able to use a ring wrench, the dealer has all the tools, we made lots over the years fixing the machines

if you have the electronic service manual it will list the wrenches used

Hilbilly · Mar 14, 2018

laurencen said:
not sure a heat gun will do much, any way you look at it they nut and fitting needs to come off, its a possibility the nut was tightened so much it fractured the elbow, the issue with the way you used the impact its not fully acting on the nut as it needs to, can you get a hammer wrench in? they are heavy short wrenches designed to be hit with a hammer, with the pipe off the elbow you mag be able to use a ring wrench, the dealer has all the tools, we made lots over the years fixing the machines

if you have the electronic service manual it will list the wrenches used

I thought about the impact wrench last night and also thought it wasn't working properly, being that it was offset. If I could get the elbow off then I could get a socket on the jam nut and use the impact properly but I can't get the elbow to break free. I'm going to see if I can get a box wrench over the elbow and onto the nut. If so, then I might be able to get a second open end wrench on the elbow and try turning both at the same time, with a little help from my SIL. Thanks for the tip. I'll also see if I can find the wrenches you mention, in my expired service manual. I might be able to see it in the parts that aren't whited out.

laurencen · Mar 14, 2018

they look like this

bigdeano · Mar 14, 2018

If you can't turn both the nut and the fitting at the same time, you may have to cut the nut with a chisel. Seems like it would be a lot easier to buy a new elbow with the nut than go thru all this hassle. Be careful to not cut too deep.

Hilbilly · Mar 14, 2018

laurencen said:
they look like thisView attachment 544012

I googled hammer wrench after seeing your post. Not sure if I could find one of those around these parts. Would likely have to order one. I'm going to try one more thing first though. I'm going to try making a hex impact wrench that will fit over the bend and with the drive hole centered over the nut. That way I can use the impact wrench with it properly aligned. It will be while before I get back to this though. I'm heading out with my son and grandson to a motocross race in Calgary. My grandson is 7 years old and an awesome rider. He has won first place in several series in his first year of racing. He has something like 50 trophies so far, going into his second season. Should be a fun boys weekend out.

bigdeano said:
If you can't turn both the nut and the fitting at the same time, you may have to cut the nut with a chisel. Seems like it would be a lot easier to buy a new elbow with the nut than go thru all this hassle. Be careful to not cut too deep.

I don't really care if the nut or bend get damaged. I suspect I will have to get a new one anyways. I was in the local town today and looked at a similar fitting. It was an ORB fitting, which I believe is the same concept and that has shed some light on how this fitting is put together. The bend and the nut are a single fitting, just in 2 pieces.

Cutting the nut may be a good approach, as long as this is an ORFS fitting and not an ORB fitting. I would need to be absolutely sure before cutting the nut because if it is an ORB then it wouldn't help and I would have another problem to add to the heap. I will double check with the dealer before going ahead with that approach and thanks for the suggestion.

laurencen · Mar 14, 2018

Hilbilly said:
I googled hammer wrench after seeing your post. Not sure if I could find one of those around these parts. Would likely have to order one. I'm going to try one more thing first though. I'm going to try making a hex impact wrench that will fit over the bend and with the drive hole centered over the nut. That way I can use the impact wrench with it properly aligned. It will be while before I get back to this though. I'm heading out with my son and grandson to a motocross race in Calgary. My grandson is 7 years old and an awesome rider. He has won first place in several series in his first year of racing. He has something like 50 trophies so far, going into his second season. Should be a fun boys weekend out.

I don't really care if the nut or bend get damaged. I suspect I will have to get a new one anyways. I was in the local town today and looked at a similar fitting. It was an ORB fitting, which I believe is the same concept and that has shed some light on how this fitting is put together. The bend and the nut are a single fitting, just in 2 pieces.

Cutting the nut may be a good approach, as long as this is an ORFS fitting and not an ORB fitting. I would need to be absolutely sure before cutting the nut because if it is an ORB then it wouldn't help and I would have another problem to add to the heap. I will double check with the dealer before going ahead with that approach and thanks for the suggestion.

you enjoy the weekend sounds like a fun time, if you visit the local dealer they will or should have one of those fittings, look and see how its put together, worst case buy it and if the other one comes off take it back

the impact does little if offset, at this point I would be using a chisel to turn the nut and if not turning cut thro it to turn the fitting

Hilbilly · Mar 14, 2018

I just ordered the fitting and o rings from the Bobcat dealer. They didn't have them in stock and it's not cheap at $40 but at least it should be the right part and I will have it on hand when I get the old one off.

Hilbilly · Mar 20, 2018

FINALLY!!!!.

The Bobcat dealer called back and suggested I get the part from a hydraulic supply place close to their location because they would have it in stock and for less money. They were right, the fitting was only $7. In the end I had to make another special tool to get the fitting off. Even with this it was darn near impossible to get the special socket over the end of the fitting and onto the jam nut. There were too many things in the way, the fuel fill hose, the fuel tank vent hose and the mounting brackets for the hydraulic pump, to name a few. I eventually managed to get the socket onto the jam nut and then get the impact wrench onto the end of the socket but it was still hard to get the jam nut to break. At first I thought the impact wasn't going to do the job either but after about 5 seconds it started to move. What a major PITA this was but my stubbornness paid off.

Here is a pic of the special tools I made and the fitting after removal. Turns out the O ring was damaged and the jam nut was jammed so tight that it wouldn't turn by itself. The jam nut and fitting turned together.