MEP-701a Generator Head Problem

[coyotegray]

I have two 701s on a M116 trailer. Both run and produce power.
The generator head on one makes more noise than the other. It sounds a bit like something rattling around but very loud. I can hear it over the generator. At first I thought a bolt was lose somewhere.

Could this be a sign of a bearing going out.? If it fails will it damage the generator any..? Any comments on the effort to replace the bearings..?


Thanks,
Andy..

 

[Speddmon]

I'm not sure what those heads are like; but the ones on the 002a and 003a's, as well as some of the larger ones, only have one bearing in them. If that bearing goes out, you could go enough off of center to start to eat into the stator of the head. The tolerances inside the heads is pretty tight. Also, if it's only a normal ball bearing, you don't want to screw up the outer race that the bearing sits in or the shaft of the generator rotor, then you're in big trouble. If you suspect it's going out, you would be better to pull the head off and take it apart and change the bearing before it does any real damage.

 

[coyotegray]

Well, I managed to find the bearing on Ebay.. Onan part number 510-0097.
Two for $11 shipped. Can't beat that.. We will see if that does it..

Andy..

 

[coyotegray]

Ok, I have the generator head un-bolted but it won't budge.. Any trick to separating it from the engine..?

 

[Isaac-1]

Assuming these are standard design generators, I have read about various techniques (although so far have not had to use any myself), the best sounding one to me is after having unscrewed the main rotor bolt (it holds the rotor onto a tapered shaft). Then make a fitting so you can screw a grease gun into the bolt hole, pressurize it with grease and then the rotor will just pop off the tapered shaft.

Ike

p.s. most other techniques involve carefully beating on the rotor with a hammer

p.p.s. you do know these single bearing units, the engine drive shaft supports the rotor on the other end, so the shaft will need to be supported with you pull it apart or else it will crash down into the stator.

 

[Isaac-1]

Never mind my last post, it looks like these units use an adapter plate, not a standard tapered shaft.

Ike

 

[jbk]

ive uncoupled a 16a gaser i think their the same. anyway you have to put something (screwdrivers or whatever) between the back of the motor and bell housing where it bolts together and pry apart until the stator comes off the bearing about an inch. the rotor will still be bolted to the flex plate.

 

[coyotegray]

Ok, I have the housing moved as far as it's going.
The bearing is accessible, sort of, the snap ring is off but the bearing will not budge off the shaft.

Any ideas on how to remove it or how to hold it in the housing so when I pull on the housing the bearing will stay in it and not on the shaft..?

Thanks,
Andy..

 

[jbk]

remove that stator, the part you just got off the bearing out of the frame and use a gear puller to get the bearing off.

 

[coyotegray]

There isn't enough room to remove the stator without getting into removing the engine, or unbolting from it etc..

I was able to find a gear puller that would fit. It's a Chinese POS so I had to replace the bolts with decent ones. The originals would strip really easy.

It took allot of time but I managed to work around the stator and get it off..

 

[Speddmon]

now that's ingenuity!!!!

how did the bearing feel when you got it off? do you think it was the source of your noise????

 

[coyotegray]

It felt diffrent than the new one. We will see once I get the new one on..

 

[coyotegray]

Ok, it's all back together and runs great. Also makes the name noise, oh well.
I learned a few things I didn't know..

I'm not going to worry about it anymore. We will run it and see what happens... Maybe it's just its personality...

One thing is that the freq would float around a little. Now it's rock solid. I think a few of the connections from the generator were lose and when I reassembled it and tightened them up it resolved this problem.

Thanks,
Andy..

 

[gimpyrobb]

Well, at least all that work helped a little! Sorry the noise didn't go away.