Predator swap done

[bobby blaize]

I just finished doing a motor swap on my old 743. The swap went great. I had an adapter made from the motor shaft to the drive shaft off the original motor. I made motor stand offs and drilled 4 holes for thru bolts and urethane bushings. This was way easier than rebuilding the diesel and way cheaper.

When I bought the skid the guy had other people work on it and he said he fired them. I should have passed on it. Apparently they rebuilt the pump and routed the hydraulic lines wrong. I started the motor after getting it all together and the drive motor on the right side works (backwards) and the left side doesn't move at all. I am going to swap hoses on the right pump and see if that fixes that side and then re-evaluate. The right side drive pump leaked when I got it. I took it apart and it was missing o-rings. It took forever to find the right set of o-rings to rebuild the pump and even then it didn't have all the right software. The big o-rings fit though so I found the right size o-rings for the small ports. Now I will be working on hydraulics until I get them working right. I will make a video after it is working and post it here so everyone can see how well the motor works with the pump. I am pretty confident that it will work fine for light duty stuff. I would not expect this setup to be good for industrial use.

 

[foton]

I assume that you are gonna use a electric fan to run on the hyrdo oil cooler,do you have enough alternator to keep the battery up??

 

[bobby blaize]

I assume that you are gonna use a electric fan to run on the hyrdo oil cooler,do you have enough alternator to keep the battery up??

I won't need a cooling fan as long as it's not running too long and getting hot. I will probably add fins to the adapter later and supply plenty of air flow. I could also add an alternator if needed, but this is just going to be used to move stuff or light digging.

 

[foton]

I can not remember if there is a port somewhere that you could add a temp. gauge to it so you would not have to guess about the temps. might be worth a look, if there is it would be a easy to do.

 

[JaNeily]

Keep an eye on those engine mounts. Engines get hot, even when not heavily loaded, and plastic melts at low temperatures.

 

[bobby blaize]

I swapped the lines on the right side drive motor and now the pump won't turn. I pulled the lines loose on the filter housing and no flow there. I have no idea what is wrong with the pump now. The motor won't start because of the pump. Anyone familiar with the 743 hose routing?

 

[Dave the Ozzie]

I swapped the lines on the right side drive motor and now the pump won't turn. I pulled the lines loose on the filter housing and no flow there. I have no idea what is wrong with the pump now. The motor won't start because of the pump. Anyone familiar with the 743 hose routing?

The issue with your right hand drive motor will be timing of the valve plate that was probably assembled one tooth out. You need to mark them when disassembling as they're timed opposite for left and right sides of machine.

 

[bobby blaize]

Thanks. I don't even know what the drive plate is, but you are probably right about me not getting it lined up since I didn't know that would be an issue. I was just trying to get it back together in the right order with all the o-rings in place.
According to my hose routing diagram the lines are correct now, but the main pump is not wanting to turn and drags the motor down so it won't even crank over. Fluid looks milky even though I thought it was empty and put new fluid in it after all the lines were in place. It seems like a circulation problem.

 

[mrbb]

if your fluid is milky you got water in the system still
when you drain fluilds, you never get them all empty, hoses and cylinders hold a LOT of fluid, including water at times

so, some times you have to drain system a few times to remove water! from it, or enough to have it looking ok!

 

[pogo]

You don't have to drain all the oil. Water being heavier than oil should settle to bottom of tank. Let it sit for a while and just loosen the drain plug a turn or two and the water should drip out first. If drain plug not at very bottom then siphon from bottom thru fill port. May have to experiment with time sitting and do several times.

 

[bobby blaize]

I am going to drain everything. I am also taking the pump out and tearing into it so there won't be anywhere for water to hide, lol.

 

[bobby blaize]

Before I tackle the Hydro Pump does anyone have any advice for marking parts or making sure I don't lose something?
I cracked all of the hydraulic lines loose and no pressure was relieved so there must be something stopping the pump from turning. My guess is the last person to work on it knew less than me and I know nothing.

 

[bobby blaize]

I just finished doing a motor swap on my old 743. The swap went great. I had an adapter made from the motor shaft to the drive shaft off the original motor. I made motor stand offs and drilled 4 holes for thru bolts and urethane bushings. This was way easier than rebuilding the diesel and way cheaper.

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When I bought the skid the guy had other people work on it and he said he fired them. I should have passed on it. Apparently they rebuilt the pump and routed the hydraulic lines wrong. I started the motor after getting it all together and the drive motor on the right side works (backwards) and the left side doesn't move at all. I am going to swap hoses on the right pump and see if that fixes that side and then re-evaluate. The right side drive pump leaked when I got it. I took it apart and it was missing o-rings. It took forever to find the right set of o-rings to rebuild the pump and even then it didn't have all the right software. The big o-rings fit though so I found the right size o-rings for the small ports. Now I will be working on hydraulics until I get them working right. I will make a video after it is working and post it here so everyone can see how well the motor works with the pump. I am pretty confident that it will work fine for light duty stuff. I would not expect this setup to be good for industrial use.

I have the entire setup apart now while I rebuild the Hydro Pump. This is the hose routing on the machine that matches the manual hose diagram. I also drew (badly) a diagram and took plenty of pictures. I hope this helps someone else in the future.