50DN Generator leaking from mounting bolt

[luvrbus]

 All depended on the owner some pulled the alternator at 50,000 miles for new bearings  some would stretch it to 100,000 you had to replace the bearing with a 2 roll bearing, seals and the alternator drive on the engine

[richard5933]

All depended on the owner some pulled the alternator at 50,000 miles for new bearings  some would stretch it to 100,000 you had to replace the bearing with a 2 roll bearing, seals and the alternator drive on the engine

I bought the bus with just over 41,000 miles on the odometer, and I doubt the original owner changed the bearings with low mileage like that.

Seems odd that they put an alternator on the bus that required bearing service so soon. Isn't this the same alternator that was on GM buses for decades before this one? Or did they change to a different type with problematic bearings.

I hate having an alternator that could be a ticking time bomb, but I don't have many options right now. Just how many of these things self-destruct so soon?

Are there shops that still work on the alternators or is getting the upgrades done not a realistic option? Maybe better to just R & R the thing once I have the budget? Seems like paying for it to be removed & replaced and then paying for a shop to replace the bearings and do an upgrade might be only slightly less expensive than just replacing it outright.

[windtrader]

>My engine only has 55,000 miles on it, so my hope will lie in the alternator lasting for a while longer.
This is a good resolution because most parts give signals of pending problems. The 50DN is pretty big and hard to imagine it blows up and stop working, most likely make noise or lose o less output.

[luvrbus]

>My engine only has 55,000 miles on it, so my hope will lie in the alternator lasting for a while longer.
This is a good resolution because most parts give signals of pending problems. The 50DN is pretty big and hard to imagine it blows up and stop working, most likely make noise or lose o less output.

Never heard a 50D make a noise before it blows,they caused problems Detroit even made special camshafts to drive the 50D  because the 50D would break the normal camshaft.belt drive 50D's wouldn't destroy a engine like the gear drive 50D's would,only GM used the gear driven alternator up to the late 70s Eagle never used 1 till the late 80's 

[richard5933]

What happens when a 50DN gives out? What's the collateral damage?

If no warning signs, did all the buses in revenue service get alternator service done every year? Even at 100,000 miles between bearing service, it would seem excessive for a coach in revenue service.

[windtrader]

Richard,


Do a bit of reading of the maintenance manual and it clearly suggests alternators should last for quite awhile. The 8v71 manual calls for looking it over a 100k interval, so you should be fine.

[richard5933]

Richard,


Do a bit of reading of the maintenance manual and it clearly suggests alternators should last for quite awhile. The 8v71 manual calls for looking it over a 100k interval, so you should be fine.

That's good to hear. I have been through the GM manual for my coach a few times and can't find anything about maintenance intervals. Are you seeing this in the Detroit Diesel Manual? If so, where abouts?

[chessie4905]

Do some searching for Delco Remy 50dn oiling and bearing upgrade. There is a pdf showing parts in kit and instructions.
Elreg distributors show the kit. Probably a different kit number for gear drive units.

[luvrbus]

The 8v71 manual is section 7 for electrical  DD tells to inspect the drive that is as far as it goes, collateral damage when one fails is a new engine you can use the block ,valves cover and oil pan if you are lucky, keep a eye on yours if the oil leak get worse then change it out gear train damage on the old 8v71 or 92 series is not a pretty sight   

[chessie4905]

Does anybody have a new gear for the end of the 50dn? I've found nos, but wrong tooth count. I have a new cup gear for it.

[DoubleEagle]

This thread makes me wonder about the status of my belt driven 50DN on my Series 60 with 666,000 miles. It has the oil lines on both ends, but is there any way to check bearing wear without taking it all off? The Eagle manual only indicates that "if generator is noisy or vibrates excessively, it should be removed for inspection and repair", and that "whenever rotor and drive end frame are disassembled for any reason, the single row ball bearing must be replaced with a new one due to the possibility of it being damaged during disassembly". Maybe it should be removed and gone over every so many XXX miles, or is it a matter of it's not making noise, so don't fix it? 

[windtrader]

richard -Better listen to Clifford, what he says sounds scary, geez. And he is spot on about the reference. I read it in a couple places but the main one is here:

[richard5933]

So I'm still left with one main question as I try and figure out my odds here...

Engine has 55,000 original miles only and has been relatively well cared for. Is the alternator likely to blow tomorrow and take out the engine or am I more likely to have a bit of breathing room here?

You guys are starting to scare me about this, especially since I don't have ability or resources to upgrade it now (and likely not in the spring either).

Just doesn't seem logical that every alternator takes out an engine if left alone.

[windtrader]

OMG, Richard. Take a chill pill and go back to bed. Hum.. for that matter I think I'm going to bed. Chances of dying of anything else will occur before that alternator explodes.


Damn Clifford, quit freaking folks out, especially as a veteran like Richard. Every other person considering a bus conversion is running away and Gary does not like that!

[chessie4905]

tick,tick,tick. There are thousands out there that have the original setup haven't  failed. Cliff only sees the thousands that did.