Radiator blower drive noise

[lostagain]

The gear drive in my MC5 rad blower is noisy, winy like. Everything is solid, the oil is up in the sight glass, so I am not sure why it is noisy. I will try belt dressing on the belt, but I doubt that it is the problem. I want to change the oil in the gear drive to see if it will quiet it down.

I have looked at the manual and it doesn't show how to drain it. Do I have to take the whole assembly off the bus? Do I suck it out the fill tube? I don't see a drain plug.

Anybody done this?

JC

[Dave5Cs]

JC mine says there is a pipe plug for draining and it takes 40 W. Sorry couldn't give you more. Looked like it was on the side and one in the back of the box.

Dave5Cs

[lostagain]

Thanks Dave,

I saw that in the maintenance manual. There is nowhere for the oil to drain once you take the plug out: it would make a mess.

Looks like taking the top lid off is easy. Then I can pump the oil out, and take a look at the gears and bearings in there. I bet there must be moisture in the oil. It probably hasn't been changed since the bus was new in '77.

I just haven't had time to get to it yet.

JC

[Dave5Cs]

Yep and lots of gears in that box. Good Luck buddy lets us know if that works.

Dave5Cs

[lostagain]

This afternoon, I took the lid off the top of the gear drive. I sucked the oil out of it with a hand pump. It was old and black, but no water that I could see. The gears look good. I cleaned the fill tube, sight glass, and vent tube. There is a little orifice at the top of the vent pipe which was plugged. Filled it back up with 40W CF2. Put the lid back on, pressure washed the whole thing, so it is all good now. We will see if it is still winy next time I take it out. Maybe the winy noise comes from somewhere else...

At least I know the gear box is serviced now.

JC

[Sam 4106]

JC,

We had a whine in our alternator last summer. I had to put in new bearings. Maybe that is your situation too. Something is begging for attention.

Good luck, Sam

[lostagain]

Sam, thanks for the pointer. If I still have a winy noise, I'll look at the alternator. How did you know it was the alternator? Mine puts out normal voltage. I guess I could shoot the bearings with the IR gun to see what the temp is after a run.

JC

[Sam 4106]

JC.

My belt driven alternator was charging when it started "singing" while on a trip last summer. I noticed the noise above the sound of our 15 KW Kubota powered generator while at Interstate Detroit Diesel shop at Sioux Falls, SD waiting for a reconditioned ECM. I opened the engine doors and the sound appeared to be coming from the alternator area, so I opened the side compartment and put my hand on the alternator. I could feel the rough bearing. The mechanic said to lube the bearings with lithium grease and repair the alternator when I got home, since he didn't know of a shop that could repair it. Greasing the bearings stopped the "singing". I added more grease often and the alternator continued to charge for the rest of the trip. After I removed the belts, to remove the alternator, I could feel and hear the rough bearing. If you have a gear driven alternator it may not be as easy to hear if it is an alternator bearing.

Good luck, Sam

[lostagain]

Thanks Sam,

I started the bus this morning. Sounds a lot better, normal like.

I will look at the alternator though. I never noticed grease fittings on the bearings, but I never looked because the alternator has never given me any trouble. It is belt driven at the back of the engine and is hard to get to. I assumed they were sealed bearings, but maybe they aren't...

JC

[TedCalvert]

Lostagain:

Hope you didn't force any water into the gearbox when you pressure washed it.

Ted

[lostagain]

Ted, I never thought of that. However, the only way would be down the small vent pipe orifice which is up high and facing up. It is less than 1/16th, maybe 1/32nd. The spray was more or less horizontal, 90 degrees to it. So I don't think anymore than a drop would have gotten in.

JC

[TedCalvert]

Pressure can force water past seals.