Mori MV35/40 spindle oil leak

[dll6]

Continuing from my previous post

https://www.practicalmachinist.com/...-spindle-counter-balance-seal-blowout-400585/

I came across a new problem while reassembling the machine that I thought warranted a new post.
Before reassembling the sheetmetal around the spindle I was checking out why the spindle lube pump and cooling fan werent running and discovered a previous owner had disconnected them at the contactor. I quickly found out why.
A few minutes after powering up the machine spindle oil began leaking out the side of the spindle housing. It appears to be coming up from the spindle oil sump, somewhere under the spindle belt drive. I think its coming up from below the driven pulley and puddling in the belt drive housing then leaking out a 3/4" or so sized hole in the left side of the Z axis, normally behind the sheetmetal covering the spindle. I cant see exactly where its coming from.
I also dont see where the spindle oil sump is vented so im hoping if I vent the oil fill pipe that comes out next to the sight glass, and maybe lower the pump relief pressure, that will fix the problem.
I really dont want to disassemble the spindle, I have no manuals on how any of that comes apart nor have I come across anything showing the inner workings of the spindle. From my previous dealings with DMG Mori they will charge me way to much to be of no help. The last time I dealt with them I paid $500 for manuals and waited 2 months for what turned out to be a CD of PDF files, to come from Japan.
Is it possible the pump is pressurizing the sump and pushing oil out the top? Or am I just grasping at straws.
Any insight would be greatly appreciated.

 

[GENERALDISARRAY]

is you cooler built into the side of the head?

I have an MV40. no belt though so not the same construction as yours. oil drains by gravity back to the cooler sump.

before modifying anything, I would investigate closer what could have gone awry. Like maybe a dead mouse in the return line.

 

[dll6]

The cooler is external, looks like a heater core and has a Dayton fan on it, the same as the cooler for the Daikin hydraulic pump. The lower spindle, area above the sump and below the tool clamp air cylinder and orientation sensor, has covers on 3 sides, the 2 side covers don't go anywhere, just covering a rubber gasket like material, maybe something for noise? The front cover is 2 pieces with a 1 piece rubber gasket material underneath that once removed exposes the spindle belt drive, driven pulley and drive pulley behind it. Tonite I'll dry out the belt drive area and see if I can tell where the oil is getting pushed out.

 

[GENERALDISARRAY]

So your cooler does not travel up and down with the spindle. Mine does.

Things were changing rapidly on these machines in the early 80s. Just trying to help differentiate all the possibilities.

 

[dll6]

It does .. Mounted on a plate above the oil pump .. Both move up and down on the spindle

 

[Vancbiker]

Make sure the pump is not running backwards.

 

[dll6]

The wiring looks original but I will definitely check pump rotation.
Thank you

 

[Vancbiker]

If the pump is running reversed it sucks oil out of the sump and overfills the head. The large hole is an overflow port to prevent excess oil from getting into the spindle cartridge and ruining/washing out the grease.

 

[dll6]

I could see how someone would think draw from the sump and out to the spindle .. It wouldn't be tough for someone to slip those little rubber colored sleeves of the wire ends and change the pump rotation to the direction they think it should be. I'll look close for a direction arrow on the pump
Thank you again for your knowledge ..

 

[GENERALDISARRAY]

i think what happens is they hook up the mains backwards. Then re-phase the coolant and hydraulic pumps. But dont realize the hidden things are also running backwards.

 

[Vancbiker]

i think what happens is they hook up the mains backwards. Then re-phase the coolant and hydraulic pumps. But dont realize the hidden things are also running backwards.

Yup, exactly. They hook it up and run the spindle and it’s good so they think the mains are right and everything else is backwards so switch them.

 

[dll6]

Verified the pump is turning the right direction. Fill cap is a pipe plug with a couple holes drilled in it. Removed it and started the machine and found where oil is pushing out. Venting isn't the cause. I took a couple pictures and will work on posting them then I'll have to finding a parts breakdown

 

[dll6]

Pictures



Oil is coming up from that gap denoted by the gen arrow (zoom in)

 

[Vancbiker]

IIRC there are o-rings at the top and bottom of the spindle cartridge to seal off the cooling ribs around the cartridge. Based on where it's leaking I'd say the top one is bad. To change, you have to remove the cartridge. The spindle has probably been changed and the o-ring damaged on installation. It's easy to do.

 

[dll6]

Does it or will it disassemble from the bottom?

 

[Garwood]

Does it or will it disassemble from the bottom?

I never had one apart, but would figure the spindle cartridge will come out the bottom like other Mori's and most VMC's.

This machine is just single speed, no gearbox? I thought the MV's were all gear drive/ 2 speed machines. Show's what I know.

 

[Vancbiker]

I never had one apart, but would figure the spindle cartridge will come out the bottom like other Mori's and most VMC's.

This machine is just single speed, no gearbox? I thought the MV's were all gear drive/ 2 speed machines. Show's what I know.

Yep, comes out the bottom.

The MV-JR and MV35 were belt drives.

 

[dll6]

Single speed .. 6k rpm spindle
I guess from the bottom I'll lose all the spindle oil .. I'll try pulling the hydraulic tool clamp cylinder out the top first

 

[dll6]

Yep, comes out the bottom.

The MV-JR and MV35 were belt drives.

You posted while I was typing .. Out the bottom it is

 

[dll6]

Any idea if MOBIL VELOCITE 3 Spindle Oil is the right stuff?