EMD Starter motor Question

Hi again,
At work we have a couple of J26C's AKA 422 classs loco's (Export boxcab SD38's) with a D32 main gen and when I kick her over, (I think) the main battery reverses the main gen to kick her over (reluctantly) and after I prime her and turn the start switch clockwise from “prime” to “start” slowly she finally cranks over and the layshaft does her thing and the roots blowers start screaming along with a puff of white smoke, anyway I am elaborating, My point is we also have two G26C’s (light weight SD38AC's) with an AR10 main alternator which uses two 32V starters in series to kick them over,…..so…..my question is from what I have gathered the Generator equipped EMD’s lack starter motors and the Alternator equipped EMD’s have starter motors ,is this because the alternator can not be reversed? And if so why it is that GE’s and many ALCo’s equipped with alternators do not have starter motors?. Again sorry about my elongated question to y’all and thanks in advance.
Regards, Derek

Alternator can not take DC to be used as motor.
the Generator can take DC battery power to crank the engine.
Most locomotives with alternators use either stater motor(DC) or Air starters

Thanks for that Dutchrailnut.

Just as a historical footnote to Dutch's answer... When AC/DCC transmission was introduced on American diesel locomotives (basically 1966, though prototypes and the very first production units were out by 1965 and GE didn't decide to standardize on AC for its higher horsepower units until several months into 1966), EMD used starter motors (three per engine, I think) of the sort used on highway trucks. This made good corporate sense: EMD was, at the time, a division of a company that also made highway vehicles. (Hint to the Australian reader: same company that owned Holden. (Grin!)) So they got their starter motors from another division of the same company. Alco, not having corporate links to an auto maker, went for air starters, which turned out to be a maintenance problem: on most railroads, Alcos were a small minority, and maintainers didn't always remember that the air starter needed lubrication.

Allen,
It’s interesting, how EMD/GM’s accessibility to certain parts albeit from a complete different mode of transport is used to save the almighty dollar, but then again, if it works why not! Also of interest is early GE U-series had AC transmission in the mid 60’s and delayed its use in their production models, was there any significant reason for this?
Regards, Derek

now were getting off topic my friend, that is question for GE forum.

(Will reply to Dash-7 off board.)

All of the older GM's that CN has running around (up to the SD75's) have two starter motors in series... 32 volt suckers. The newer SD70M-2's went back to an air starter, and it's been problematic... I hate the SD70M-2's with a passion.

There will be more use of air starters in the future as designers have now recognized that low system voltage during cranking with electric starts in cold weather can cause some electronics to drop out which can interrupt starting or prevent you from starting altogether. In fact the Caterpillar PL module used as a programming interface in some of their applications had software that dropped it out at 20 volts and locked it out completely after five events. You had to call your Caterpillar dealer to send a service technician out to reset the module before you could use the locomotive again.

MX

Wow makes you wonder if it was made that way so you pay CAT a service fee!

I like my Direct air start. No moving parts! Another good idea from Cleveland that didn't catch on at EMD..

dash7,
Everything about Cat (right down to the design) is built around making you call the dealer for service...
Tom

Just remembered, at another company we tried out several turbine air starters. They turned out to be very maintenance free; no need for an oil mist lubricator, very powerful (IIRC, just one instead of the EMD usual two.), and able to handle the occasional slug of water, which is a common problem in marine installations due to scrambled piping layouts. Plans were to convert all EMD's over to these at overhaul, but the company disappeared from under me before I ever saw one on my boat...
Tom

BilgeRat wrote:dash7,
Everything about Cat (right down to the design) is built around making you call the dealer for service...
Tom

Its part of a package deal where CAT furnishes the engine at a low price, all financing - not so low, and a service contract where they make it all up on the cost of the parts. For marine engines CAT is the lowest cost per horsepower. The legend is that you had better buy an extra engine so you can strip it for parts.

Rick,
Correct, in all regards. This is how gambling boats in the Midwest came to have Cat power almost exclusively; Cat Finance cut such sweetheart deals that they couldn't say no considering they (the boats) were a short term thing not planned to last past two or three overhauls. I remember having the local dealer quote us for a center section overhaul on a 3508 on a gambling boat in the mid 90's; when National Marine would overhaul your 645 marine EMD for $1800 per hole with an 8000 hour warranty, Cat wanted $5000 per hole for that much smaller engine. phew, go rob a bank.

I think that philosophy permeates the whole organization. World wide, engine design has become much more modular (i.e. more like EMD) except for Cat. Any one thing you need to work on on a Cat, there are between 2 to 8 other things you have to get out of the way and then put back, which translates into more billable time. Clearances are tight on most all fasteners (same time thing), and Cat dealers keep an absolute hammerlock on information. I had tried to get manifold pressure @ load figures for a 3306 generator engine and had the call shunted to service scheduling! They weren't going to give us that info, just send it out with a service tech and a bill. I'm off topic here, but had to vent a little...
Tom