50DN Generator leaking from mounting bolt

[richard5933]

The mounting gasket on my generator was replaced last year, and on the past couple of trips I'm again noticing a leak. This time it's a tiny amount coming from the mounting nut in the 3 o'clock position. Not a lot, but enough to be noticeable after only a few hundred miles.

Question #1 - Is this worrisome or just an annoyance?

Question #2 - Is there some type of copper crush washer involved here that could make for a simple repair?

Hate to think about pulling the 50DN again, but if it's necessary then it's necessary.

[Utahclaimjumper]

Have you simply tryed to tighten those bolts..>>>Dan

[richard5933]

Have you simply tryed to tighten those bolts..>>>Dan

Was my first thought. Couldn't even budge them with a 14" breaker bar. I imagine the shop torqued them properly.

[chessie4905]

Try a soft copper washer. Little lost for the effort.

[Utahclaimjumper]

If the nut has a spiral washer under it,, it's probably your problem..>>>Dan

[richard5933]

In the end there was some seeping from a few of the studs. They were removed, cleaned, and resealed with some thread sealant and the addition of a copper washer. Everything looks dry and tight for now.

Apparently my starter gasket had also given way creating quite a mess on the rear of the engine, so it was dealt with. For now I have a dry engine. For now.

Seems that time and non-use don't help gaskets last any longer. Nearly four years later and I'm still discovering gaskets & seals which went bad from lack of use.

[chessie4905]

All 2 cycle Detroit Diesel engines in our coaches will develop leaks as the miles accumulate and natural blow by increases. Same as air leaks. You just need to keep after them. Boat owners use Walker Air Seps to keep their engine rooms clean. They will work on coaches, but at 400 some bucks for one, most wont spring for one.
Same technology GM uses on their car and truck diesels since 1980 to control blow by. Just a lot larger for ours.

[luvrbus]

Most of the time a leak at around 3 clock on the 50D is from the 1/8 inch supply line has a hole or the fitting is cracked ,and the leak around the starter is the air box drain

[richard5933]

Most of the time a leak at around 3 clock on the 50D is from the 1/8 inch supply line has a hole or the fitting is cracked ,and the leak around the starter is the air box drain

The oil line on my 50DN comes to the tail end of the alternator. The leak(s) were around the mounting gasket - is there another oil line I'm missing?

[luvrbus]

The oil line on my 50DN comes to the tail end of the alternator. The leak(s) were around the mounting gasket - is there another oil line I'm missing?

It has to oil the front bearing too,this not a great photo but you can see the line going to the front bearing

[chessie4905]

There was an update to add oiling to both ends. Last I saw, the old ones can be upgraded to new oiling. Go to their bulletins to see the info. They used to sell the upgrade kit.

[richard5933]

There was an update to add oiling to both ends. Last I saw, the old ones can be upgraded to new oiling. Go to their bulletins to see the info. They used to sell the upgrade kit.

I found the bulletin you're talking about, and now I can confirm that I don't have the second oil line to my alternator. From the looks of the installation instructions, it's way beyond my abilities right now. Assuming I can find the kit, the alternator must be pulled and disassembled to install it.

My engine only has 55,000 miles on it, so my hope will lie in the alternator lasting for a while longer.

[luvrbus]

That was a weak point on the 50D surprises me it wasn't done Delco paid for the upgrade for 2 years, those require a lot of oil flow 2gpm at highway speed and .5 gpm at idle bus  people got into trouble restricting the flow more than specs call for trying to increase the oil pressure 

[richard5933]

Bus was bought new in 1974 and used as a motor home for a few years, up to about the early 80s from what I can tell. It had only sporadic use after that. I'd bet that the bus was just forgotten about when the upgrade kits were being paid for by Delco.

Unless this is something which is more likely than not to cause a problem in the near future, it's going to have to wait for now. I've got upcoming surgery (hernia repair) which is going to make it impossible for me to do the work, and my paying the medical bills will make it unlikely we'll want to spend the money to have it done at the shop right now.

Do you have any stats on when problems with these 50DN alternators would typically appear? As in, after how many miles? Just trying to get an idea of what kind of time bomb we have or don't have.

[chessie4905]

I doubt Delco Remy posts stats. They just list service bulletins. There is a coach website that has for info though. I believe they went to a wider bearing also. Ill see if I can find that site/ info.