743 Control Valve Bushing Question / Issue...

[BattleCat]

Here is the short version of my story... Have lift spool leak - did my research prior to starting the job - when I pulled the spool out of the block there were no bushings as the parts diagram calls out (I used my serial number on Bobcat parts book webpage) - I attempted with my finger and some picks to pull them out if they were stuck but no movement.

 

[BattleCat]

Additional pics

 

[brdgbldr]

Here is the short version of my story... Have lift spool leak - did my research prior to starting the job - when I pulled the spool out of the block there were no bushings as the parts diagram calls out (I used my serial number on Bobcat parts book webpage) - I attempted with my finger and some picks to pull them out if they were stuck but no movement.

View attachment 8288

Make sure that there is not more than one control valve listed in the parts list for your machine.

Also, these parts catalogs are not without their errors. I would suggest just putting In your model number and taking a look at the other control valves shown for different serial numbered machines. I think the latest 743 models do not have the bushings.

 

[Markle]

I did what brdgbldr said…my 743 did not have bushings . The Gresen valve spools on some 743s do not have bushings

 

[ward]

part # 12 is bad I have seen it many times.

 

[BattleCat]

Thanks for the replys. I did look at the other SN breaks prior to posting here and they all show bushings.

Markle is showing the tilt control section. I am working on the Lift spool #7 in this diagram and my control valve body matches that shown in the same diagram

Everything else was there detent springs (2) and balls (4) I also replaced the small o-ring under the stud in the spool. I am convinced that there are no bushings or this is an aftermarket unit.

Do they stamp the block anywhere so I can determine if this is an OEM block and is anyone aware of aftermarket producers of this assembly?

 

[ward]

the tolerance of the spool to valve body is so close that oil becomes the seal and the little that leaks by is kept in by the o ring, dirt wears out the o ring and it weeps oil out, if oil is spraying out you need a new valve.

 

[BattleCat]

Roger that. Do you have any insight as to why the parts book calls out bushings (#8 In diagram above) and there is nowhere for these bushings to go in my valve block?

 

[oiu789]

Was the valve block changed out in the past? They might have not used a direct replacement.

 

[BattleCat]

See post #6

 

[Markle]

See bobcat hydr spool manual attached. According to this, only older valve blocks had bushings.

 

[BattleCat]

Thanks Markle! I skimmed it on my phone and it looks like this is what I need. Will dig it to it when I get in front of my computer

 

[Dave1234]

That component repair doc is a great help. Thank you. Makes me wonder--are there other similar Bobcat docs for other hyd components? I have never seen a listing, and others have asked Bobcat with a 'have no idea what you are talking about' response.

 

[Markle]

Great if someone can save it in archives here.

 

[brdgbldr]

That component repair doc is a great help. Thank you. Makes me wonder--are there other similar Bobcat docs for other hyd components? I have never seen a listing, and others have asked Bobcat with a 'have no idea what you are talking about' response.

I have come across other documents that do not seem to be available anywhere anymore.

I have a "Bobcat Technical Service Manual" that I picked up from a Bobcat technician off of eBay years ago. It came with other Bobcat training manuals also.

It would be nice if there was a manuals library / archive where all of these historical manuals were kept. Most of these old manuals are obsolete to dealers and get tossed out.

 

[Dave1234]

I have come across other documents that do not seem to be available anywhere anymore.

I have a "Bobcat Technical Service Manual" that I picked up from a Bobcat technician off of eBay years ago. It came with other Bobcat training manuals also.

It would be nice if there was a manuals library / archive where all of these historical manuals were kept. Most of these old manuals are obsolete to dealers and get tossed out.

Any chance of getting scans of those relevant to a 742B?

 

[brdgbldr]

Any chance of getting scans of those relevant to a 742B?

Here are some. If you need the 742 manual I will need an email address because it is too big.

 

[brdgbldr]

Any chance of getting scans of those relevant to a 742B?

Here's a good thing to have:

 

[Dave1234]

Here's a good thing to have:

Thank you for all of them!!! I do have the repair manual, so don't need you to email it. You are great.
Dave

 

[BattleCat]

Well… After more time than I wanted to put into online research and the phone to find an aftermarket supplier of the control valve (never found one) and why this block didn't have bushings. I was able to find a gentleman from parts support and he said he was 99.9% certain that all 743's had the bashings. I replied I bet I'm in the .1%… wish I could've called that in to Vegas.

Anyway he was a good guy and was willing to dig into the issue. He reported back that there was a period of time ~16 months where they trialed a different design (mine w/o bushings) then went back to the original design (w bushings)