'89 Bobcat 743 control valve

[antfarmer2]

Are you saying the engine decouples from the pump unit, so the pumps and all that can stay in place? If so, I'm guessing that would be at one of those U-joints, but I don't recall seeing one yet. How difficult are they to reach? How many hours for an experienced person to do an engine R&R? I can multiply that by whatever factor I think is suitable here! Obviously, I would like to fix this properly, but am also trying to remain practical.

A coulple wires off the starter hoses off the engine,fuel line and four bolts on the exaust and four bolts holding the engine and slide it out

 

[antfarmer2]

A coulple wires off the starter hoses off the engine,fuel line and four bolts on the exaust and four bolts holding the engine and slide it out

Ujoints are a hundred bucks

 

[antfarmer2]

Ujoints are a hundred bucks

Can all be done in a afternoon with beer brakes get the parts first

 

[billrbg]

Can all be done in a afternoon with beer brakes get the parts first

I can leave the radiator and muffler in there and separate the engine and pump at the spline?

 

[antfarmer2]

I can leave the radiator and muffler in there and separate the engine and pump at the spline?

Yep ......

 

[Tazza]

Yep ......

4 engine mounts, 2 coolant lines, few wires, exhaust hose and the engine comes out. No need to remove the radiator and muffler.
To pull the control block is a massive job, don't even try unless you need to.

 

[billrbg]

4 engine mounts, 2 coolant lines, few wires, exhaust hose and the engine comes out. No need to remove the radiator and muffler.
To pull the control block is a massive job, don't even try unless you need to.

"To pull the control block is a massive job" Is that true even after the engine is removed??? Are you saying I should just crawl in there after the engine is out and do the spool seals without removing the valve?

 

[antfarmer2]

"To pull the control block is a massive job" Is that true even after the engine is removed??? Are you saying I should just crawl in there after the engine is out and do the spool seals without removing the valve?

Yep much easyer and faster buy some extra springs and balls they are cheap and you will need them LMAO

 

[billrbg]

Yep much easyer and faster buy some extra springs and balls they are cheap and you will need them LMAO

I understand about having some extra balls and springs, but a least I will have a chance of not losing too many since I will have decent access! My plan now is to finish up the job at my son's house just keeping the fluid level up. Then I'm going to drive it home and do this valve business where I have a hoist, am indoor, and have all my tools handy. You may not hear from me for a while.

 

[antfarmer2]

I understand about having some extra balls and springs, but a least I will have a chance of not losing too many since I will have decent access! My plan now is to finish up the job at my son's house just keeping the fluid level up. Then I'm going to drive it home and do this valve business where I have a hoist, am indoor, and have all my tools handy. You may not hear from me for a while.

Hope you have a high roof will need room to flip the cab up cheak it first so you don't get stuck use a chicken band to hold the balls in then slide the back on

 

[Tazza]

Hope you have a high roof will need room to flip the cab up cheak it first so you don't get stuck use a chicken band to hold the balls in then slide the back on

Yes, even with the engine out, it is not easy, you need to remove tube lines to get it out, access is really not good. I only ever pull the control block to work on it when the tube lines are coming out too.
With the engine out, there is heaps of room to get in there.

 

[Dameon]

Yes, even with the engine out, it is not easy, you need to remove tube lines to get it out, access is really not good. I only ever pull the control block to work on it when the tube lines are coming out too.
With the engine out, there is heaps of room to get in there.

Being pretty much a novice Bobcat mechanic, I pulled my engine in less than an hour. Do what I did... take digital pictures of all the connections, wiring, etc., before pulling the engine. In fact, take two pictures of everything if you have an "unreliable" camera. Have a 5 gallon bucket to catch the coolant. No other fluids should escape (maybe a little diesel). I slid my engine straight out onto a hydraulic lift table, or you can just build a small stand from 2x4's. The lift table I have is on wheels, so that made it easy to roll away from the Bobcat to work in the engine bay. Drill some extra holes in the bottom of the fan shroud. Clean out all the crap you can while the engine is out. To put the engine back in, it took me about about the same as taking it out. The longest part was lining up the splined shaft and engine coupler. If you have a person with small hands, that's willing to risk getting pinched, that part will go much easier.

 

[billrbg]

Being pretty much a novice Bobcat mechanic, I pulled my engine in less than an hour. Do what I did... take digital pictures of all the connections, wiring, etc., before pulling the engine. In fact, take two pictures of everything if you have an "unreliable" camera. Have a 5 gallon bucket to catch the coolant. No other fluids should escape (maybe a little diesel). I slid my engine straight out onto a hydraulic lift table, or you can just build a small stand from 2x4's. The lift table I have is on wheels, so that made it easy to roll away from the Bobcat to work in the engine bay. Drill some extra holes in the bottom of the fan shroud. Clean out all the crap you can while the engine is out. To put the engine back in, it took me about about the same as taking it out. The longest part was lining up the splined shaft and engine coupler. If you have a person with small hands, that's willing to risk getting pinched, that part will go much easier.

Well, the great day has arrived. We topped-off the hydraulic fluid Fri, drove it home Sat, and I pulled the engine this morning. It went fairly easy. Just one hour? More like three for me, but I was doing it "out in the field", maybe 400' from my shop and tools, and I was working alone. Knowing now how to do it, I probably could get it out in one hour, but I am old, no desire to rush. the only problem is all four of the screws holding the exhaust pipe to the exhaust manifold twisted off. I was kind of expecting that, so not such a bummer. It should be easy enough to drill those screws out since it is now out in the wide-open. I'll even make a drill-jig so that I can get as centered on the screw nubbins as possible. So, here is the question: Does that fan shroud come out fairly easy? It now looks possible to get to the control valve, with the engine out, but looks like it would be even sweeter with the shroud out of the way!

 

[antfarmer2]

Well, the great day has arrived. We topped-off the hydraulic fluid Fri, drove it home Sat, and I pulled the engine this morning. It went fairly easy. Just one hour? More like three for me, but I was doing it "out in the field", maybe 400' from my shop and tools, and I was working alone. Knowing now how to do it, I probably could get it out in one hour, but I am old, no desire to rush. the only problem is all four of the screws holding the exhaust pipe to the exhaust manifold twisted off. I was kind of expecting that, so not such a bummer. It should be easy enough to drill those screws out since it is now out in the wide-open. I'll even make a drill-jig so that I can get as centered on the screw nubbins as possible. So, here is the question: Does that fan shroud come out fairly easy? It now looks possible to get to the control valve, with the engine out, but looks like it would be even sweeter with the shroud out of the way!

Not to hard you can take out the rad cooler and muffler in one piece with the metal plate four bolts on the back and three on the front I think then two hidden on either side the heads are by the tanks two hydro lines and lift it out a bit heavy then two bolts for the shroud one top center and one in the bottom center while you have it out time for a good cleaning also check the two lines that cross at a 90 just to right of center they wear there

 

[billrbg]

Not to hard you can take out the rad cooler and muffler in one piece with the metal plate four bolts on the back and three on the front I think then two hidden on either side the heads are by the tanks two hydro lines and lift it out a bit heavy then two bolts for the shroud one top center and one in the bottom center while you have it out time for a good cleaning also check the two lines that cross at a 90 just to right of center they wear there

Well, this is more of a cry for pity or a rant, I'm not sure how you can help, but here goes: The engine came out easy, the shroud "not so much"; but it's out too, so I have good access to the rear of the control valve. However, the front side (where linkage connects) is buried beyond my reach by three hydraulic lines, especially the -12 one going to the reservoir. I bought some crowfoot wrenches to remove those lines and started out with the connection of the largest one (the -12) where it attaches to the "Block" about 6" in front of the Control Valve. That SOB is so tight all I can do is bend my 1/2" breaker-bar, using a long cheater-pipe on it. There is no rust on there, but I soaked it with some penetrating-oil. I have also heated it with a propane torch and have hammered on the nut flats, trying to get a minute amount of "give" someplace. The only thing I can think of to do now is to cut the nut or cut the hose. Either way I lose the hose, and maybe the fitting into the Block. I don't think a longer cheater-pipe is the answer, as the breaker-bar handle is bending enough that I run out of room to swing it (about 30 deg!). I'm pretty sure much more torque will just ruin the breaker or crow-foot, and that's assuming I could find a way to get more swing. I have also considered fabricating a special wrench that could get a 6-point grip and with a stiffer handle, but sacrificing the hose seems more practical. Any other suggestions?

 

[antfarmer2]

Well, this is more of a cry for pity or a rant, I'm not sure how you can help, but here goes: The engine came out easy, the shroud "not so much"; but it's out too, so I have good access to the rear of the control valve. However, the front side (where linkage connects) is buried beyond my reach by three hydraulic lines, especially the -12 one going to the reservoir. I bought some crowfoot wrenches to remove those lines and started out with the connection of the largest one (the -12) where it attaches to the "Block" about 6" in front of the Control Valve. That SOB is so tight all I can do is bend my 1/2" breaker-bar, using a long cheater-pipe on it. There is no rust on there, but I soaked it with some penetrating-oil. I have also heated it with a propane torch and have hammered on the nut flats, trying to get a minute amount of "give" someplace. The only thing I can think of to do now is to cut the nut or cut the hose. Either way I lose the hose, and maybe the fitting into the Block. I don't think a longer cheater-pipe is the answer, as the breaker-bar handle is bending enough that I run out of room to swing it (about 30 deg!). I'm pretty sure much more torque will just ruin the breaker or crow-foot, and that's assuming I could find a way to get more swing. I have also considered fabricating a special wrench that could get a 6-point grip and with a stiffer handle, but sacrificing the hose seems more practical. Any other suggestions?

Hard to belive they are that tight but I would try putting your crows foot on and pull till your half inch breaker is bending get some help to hold it and wire it tight then heat then hit it fast with the air chisle

 

[antfarmer2]

Hard to belive they are that tight but I would try putting your crows foot on and pull till your half inch breaker is bending get some help to hold it and wire it tight then heat then hit it fast with the air chisle

Or you could just change the seals with it in now that you have more room

 

[billrbg]

Or you could just change the seals with it in now that you have more room

Oh, I was bending the breaker-bar... a lot! I'm kind of surprised the 1/2" drive didn't twist off. I certainly am going to change the seals with the valve in place, one look at all those hard-lines that would have to be busted loose, probably at both ends, convinced me of that. I just couldn't get into the front (linkage) end, not even enough to get the clips and pins out. Notice I said "couldn't"? I can now, I got that big hose out. I went back to the other end, at the oil tank, and that one was fairly easy to loosen. Which is good, since the fitting there goes into that plastic tank and breaking that tank would be easy to do if I had to torque on that end as much as I was the other. After that end was loose, I just unscrewed the hose complete with the other fitting from the Block in front. I started to take off a boot on the front of one spool, but couldn't get the retainer to come out. Does that use just one 1/4-20 screw to hold it, or is there another 180 deg away that I can't see or feel right now?

 

[antfarmer2]

Oh, I was bending the breaker-bar... a lot! I'm kind of surprised the 1/2" drive didn't twist off. I certainly am going to change the seals with the valve in place, one look at all those hard-lines that would have to be busted loose, probably at both ends, convinced me of that. I just couldn't get into the front (linkage) end, not even enough to get the clips and pins out. Notice I said "couldn't"? I can now, I got that big hose out. I went back to the other end, at the oil tank, and that one was fairly easy to loosen. Which is good, since the fitting there goes into that plastic tank and breaking that tank would be easy to do if I had to torque on that end as much as I was the other. After that end was loose, I just unscrewed the hose complete with the other fitting from the Block in front. I started to take off a boot on the front of one spool, but couldn't get the retainer to come out. Does that use just one 1/4-20 screw to hold it, or is there another 180 deg away that I can't see or feel right now?

Don't know that one have not done mine yet still learning

 

[antfarmer2]

Don't know that one have not done mine yet still learning

But looking at OM's pic looks like just the one