Fan Pillow block

Emcemv · June 15, 2014, 06:08:10 PM

My MC-7 is a combo and I think it has the same side radiator and fan drive as a Scenic. The photos below show the fan drive pillow block and from there the fan drive goes to the right angle gearbox that the fan is mounted to. I thought the pillow block bearings were shot but upon taking it apart, the bearings are fine, the shaft has actually been rotating in the bearing and now the shaft is worn down by the bearing race. A messy situation, only solution I can think of would be to build up the shaft by welding and then turn it down in a Lathe. I was wondering if this is the same pillow block that is used in the Scenic, I have Scenic manual and it shows part #GBK10000-A for the pillow block and pulley but the assy in the manual looks a bit different than what I have. The pillow block has some numbers on it, #020720. Anyone seen anything like this?? Anyone have one in good shape?

eagle19952 · June 15, 2014, 06:20:31 PM

I am sure a good machinist can cure that...
But as I look at your pictures it seem that one shaft to bearing surface is much more deeply worn, I assume that end is the fan end, I would wonder if something was seriously out of balance, as if the shaft was oscillating.
Having said that I have zero experience with the MC-7.
But I would try to find out the why.

Emcemv · June 15, 2014, 07:45:34 PM

Eagle, actually the worn part of the shaft is on the drive pulley side, it's been wobbling for a while, I thought it was a bad bearing. I guess the big pulley could be out of balance. Will check that.

eddiepotts · June 16, 2014, 07:36:16 AM

I would not be spending any time with that shaft. By the time your done paying for the weld repairs then buying a new shaft anyway, it will be money down the drain. You can buy those bearings anywhere. They are easy and cheap at this point. they are costly on the road. the vibrations that shaft has given to them will cause fretting if you can feel them or not. Bearings never heal they just die. As far as the shaft goes if you weld on the fit you will never get it strait again. you will have a wobble in it forever and constantly destroying bearings. You will also change the temper of the metal which will lead to cracking or an instant snapping off. You can throw your dart on the map where all this will happen but it will. I Don't want to sound so gloom but welding is not your answer. If you post the numbers on the bearings I will help you source them. Bearings overnight in the freezer and ten minutes of installing them you will be back to new design and not the beginning of a new catastrophic failure.

eagle19952 · June 16, 2014, 08:38:34 AM

Of course I would not suggest that you re-use the old bearings, with whatever shaft you reinstall.
I was simply under the impression that the shaft was obsolete and made of unobtanium.

eddiepotts · June 16, 2014, 09:28:49 AM

I was just going off the fact that he says after he took it apart that the bearings were fine. This is a big misconception on his part. If the shaft is not available in any junk pile, my vote would be to have a whole new shaft made. I would be looking for a shop that specializes in axles.

eagle19952 · June 16, 2014, 09:37:11 AM

bearings are cheap.....shafts are not

Emcemv · June 16, 2014, 01:32:38 PM

Hey guys, good advice, I actually have several sets of new bearings for this, that's not the problem, the shaft is the problem. I'm trying to figure out if my assy is the same as a scenic or I have something special and it's unobtainium. I was hoping one of the scenic owners would chime in. I actually have a scenic manual and the pillow block looks different than what's in the manual.