I'm going to reinstall a 50dn alternator that was removed before I purchased conversion. Gear train is fine, just plated over. Wires are there, just taped off. Anyway, I have two 50dn's, One a takeoff from my parts coach and one I purchased from Nimco a few years back. The Nimco one has the oil line upgrade one it but fewer teeth on the drive. Bearings are quiet when you hand spin it. No tag on it and painted gray.Can I just install proper gear and use it? Anything I not realizing?
I'm going to install new drive and driven gear and do the adapter centering procedure in the manual with dial indicator.
I know some (Cliff) don't care much for the gear driven ones due to cost of catastropic failure, but otherwise, any other thoughts?
One is for the Sun gear drum drive setup (planetary) the other is for a direct drive
Better to convert the rear drive to a double V-belt and then run a couple of 160amp alternators from trucks ($160ea), cheaper and if one locks up will only take out the V belt, not the drive train ($$$$). Good Luck, TomC
I have used the direct drive off the engine 50DN for over 30 years on various engines and never had an issue. Be careful when you install the 50 DN to the engine as there are several gear combinations and they are not interchangeable. You must have the proper one or you will bust the housing.
Quote from: Bill Gerrie on June 06, 2018, 11:53:11 AM
I have used the direct drive off the engine 50DN for over 30 years on various engines and never had an issue. Be careful when you install the 50 DN to the engine as there are several gear combinations and they are not interchangeable. You must have the proper one or you will bust the housing.
You have been real lucky Bill Gerrie,ask LVMCI what can happens he is the most recent causality I know, it cost him a 8v92TA last year
People also think they can just bolt it on with out setting it up with prussion blue to establish the fit,,a real no-no.>>>Dan
I've heard that but I guess till I have trouble I won't know for sure. I sure hope it doesn't happen to me.
Quote from: Bill Gerrie on June 06, 2018, 07:24:24 PM
I've heard that but I guess till I have trouble I won't know for sure. I sure hope it doesn't happen to me.
I hope it never happens to you either it is sad seeing grown men cry :o
I know there are specific gear combos for the 4905, at least and will use the ones that are of the parts coach which match the tooth count specified in the parts book. I was wondering if the gear drive 50 Dn's are all the same otherwise, and we're run faster or slower in city bus use with different engine....8-71, 6-71, 6-92. I do know they make a belt driven 450 amp 50dn plus. Just didn't know if the one I have is same output as in the 4905. I will use the dial indicator on the drive gear to pilot hole in adapter and adjust as necessary to obtain .002 or less run-out as specified in manual.
If you are going to use the 50D ,I'll check my boxes in the next few days I have the Kent/Moore J-29883 fixture to set those up if it hasn't grew legs and walked off
Thanks.
Found this info on improvements over the years.
http://busfixx.tripod.com/busservice/id23.html (http://busfixx.tripod.com/busservice/id23.html)
When my 50DN gave out, it stopped charging-but was still turning. Since it was overheating, I disconnected the big battery cable till I was able to replace it. Being a V-drive, the alternator was easy to get to through the side engine access door, but with it in about 2ft, I made a ramp out of 2-2x4's (weighs 100lbs!). I took it in and they gave me a rebuilt exchange with all upgrades already done. With also changing the big transistorized voltage regulator to a digital voltage regulator (about the size of a pack of cigs), it cost right at $1,500. When I mounted it back in (major grunt to get it back in position-even with the 2x4 ramps), I estimated the clearance and bolted it down. Still working many years later-guess I lucked out.
Only thing, even with the digital voltage regulator, my voltage surges up and down-hence you can see the headlights getting brighter and dimmer quickly with the voltage regulator kicking in and out. I also run with the headlights on at all times to give the alternator a load, otherwise the alternator charging light comes on. Good Luck, TomC
Funny thing about the 50D gear driven a bus engine is the only place you will find one,not saying truckers are smarter than bus people :D but replacing the belts is a easier job
The average truck doesn't need a 270 amp alternator either. Although I've seen a few that may need 1000 amps with all the lights some add.☺
The new Prevost buses I drive have 3 alternators. Belt driven. They have gone to 8 electric fans on the radiator and the charge air cooler. The fans only come on one at a time going up a hill on a hot day. The alternators only produce on demand. Modern technology...
JC
Electric fans on radiators are fine when the sizing of the radiator is made for the reduced air flow with the electric fans. Electric fans work great on transit buses since they are stop and go. Trying to retrofit electric on our buses just don't work. Good Luck, TomC
The 8 work on a Prevost when all 8 are on you need a safety belt those will suck you in when you walk by, lol old Two Dogs of the past on the Bus Nut board would be proud of the electric fans on the Prevost
Yup, a package deal.
Radiator and fan air flow have to be partners.
Did anyone find 2-dogs, the debate raged years ago...
Happy coaching!
Buswarrior
Prevost had a few hiccups at first but all is well now they work with the same radiator as the mechanical drive saving 50 hp.Boomer taught us this 15 years ago on his Eagle that everyone said would not work lol it is still working with a electric fan
The Prevost I saw didnt have a two cycle engine. There isn't enough space in front of radiators for the number of fans it would take.
I will soon remove my grear driven 50DN and replace it with a belt driven/air cooled Delstar alternator of the same frame size.(http://www.delstar-hd.com/results.asp?q=8600191 (http://www.delstar-hd.com/results.asp?q=8600191))
This alternator run cooler than the oil cooled 50DN even in a hot engine comparment (we have tested it on a couple of transit buses where i work).
It also has higher Amps output at low engine rpm.
Another good thing about belt driven alternator is the ease of access to inspect cable and terminal.
For the air cooled folks, check out an MCI J model.
There is a duct from the curb side engine room access door to the alternator, to feed it cooler outside air.
Heat kills alternators, and those of us who are charging big battery banks while jumping between boondocking sites, are making a lot of heat.
The hotter engine rooms are also just on the cusp of being in the hands of busnuts. Average engine room temps have risen dramatically between before and after various EPA thesholds, and some manufacturers didn't get some years sorted out as best as they could have. Know Whatcha got!
Happy coaching!
Buswarrior