LIRR Push-Pull Train Concept Overview 1971-72 - Power Packs, P72's , and more

A diesel train consisting of the ex emu cars (MP72/MP75) with only a GP38/MP15 or with 2 MP15 units. The MP15 unit was modified to supply hotel power and had a “P” Applied to the number
Such as P161, P171
These units could be switched to power themselves if need be. But we’re otherwise operated as FA/F units supplying the MU 600VDC to the coaches

WE - Good reminder of the MP15 "P" units which should not be overlooked...
As we know the LIRR installed a switch that turned on and off the traction motors as needed...
With the proper cable links they supplied HEP to cars - a clever unit modification...

My favorite example of the MP15s in action was on the Ronkonkoma- Greenport Scoot beginning in
January 1988 (until around 2000) which was two MP15s and two coaches which I began to nickname
"The Sandwich Train"...An interesting variation of that train was two red stripe parlor cars (outside
of the East End tourist season) offering sometimes a parlor car ride for a regular fare...MACTRAXX

Wouldn't the HEP use some power from the locomotive and reduce its pulling power?

Frank wrote: ↑Thu Feb 23, 2023 10:02 pm Wouldn't the HEP use some power from the locomotive and reduce its pulling power?

Frank: NO...MP15Ps in HEP supply mode were basically a non-powered control cab.
There is no electricity being supplied to the traction motors in the HEP setting...MACTRAXX

Given the MP75s were not converted to push-pull until 1973 (and the MP72s later), they could have used standard
480v HEP, since the NJDOT/EL Comets had them as early as 1970.

R36: The first LIRR push-pull train was placed into service on May 25, 1971. (source: RMLI archive research)
The original equipment designated were 44 MP72 cars and six FA2 control cabs (601 to 606) initially.

The LIRR decided to stay with 650/600 volt DC power trainlined from the FA prime mover which became
basically a HEP generator with the traction motors disconnected and/or removed for push-pull service.

See this topic for further information about this subject:
lirr-push-pull-train-concept-overview-1 ... 70549.html
(14 posts - November 5 to 27, 2019 bumped up to current topic post)

P.S. These two topics can be combined together...MACTRAXX

RGlueck wrote: ↑Wed Nov 27, 2019 9:05 am Once again, why were certain FA power cars stripped of their 244 power plants and changed over to the Detroit Diesel sleds? These were mostly the ex- SP&S FA1's?

RG - After going back to research this topic I noticed your question about the control cabs...
The late John Scala's book "Diesels of the Sunrise Trail" mentioned this subject with pictures of the DD sleds.
A smaller and more fuel-efficient generator was the change made along with a block of concrete added for
ballast weight when the original prime movers were removed - I believe there was mention about specific
units that were modified in this manner...MACTRAXX

Here's what I have:

The Alco FA-1's were rated at 1500 or 1600 HP, depending on when they were built. For use as Head End Power, the LIRR removed the traction motors and reduced the horse power (de-tuned the engines) because they didn't need that much HP to run the generator for lighting, heating or cooling the passenger cars. These are the "untouched" engines in your email excerpt.

In 1978, the LIRR purchased engine-generator sets from Detroit Diesel. They consisted of a small diesel engine, a generator and a control panel all mounted on a single steel frame. The original Alco engine and generator was removed from the FA body and the Detroit Diesel "sled" dropped in. The sleds were fuel efficient and quiet running. Info: Steve Rothaug

Detroit Diesel powerpack.jpg (48498 bytes)Detroit Diesel sled being prepared for installation in the first F7 converted for HEP use. Morris Park. Photo: Steve Rothaug
The FA's that were converted over had Detroit Sleds installed in 1983.


Units that had the first HEP modification, but untouched were:
607
609 (scrapped in 1993)
611
612 (destroyed, and scrapped in 1993 due to a fire)
613
614
616

Units that had HEP modification were: Also, those 2 FA's were the first ones to have the quieter HEP's: 615, 617

The quieter sleds were in fact placed in 1987. 605, and 606 were totally rebuilt to the point that where the original engine room doors, and steps were, were taken out, and relocated. c.1983-84, or so, such FA's as 605, 606 had the quieter engine.

In the late 80's early 90's however, 615, and 617 had quieter engines installed, or maybe mufflers because besides that, there was extra grilling placed in front of the existing grille that was left for exhaust when the HEP's were converted. 605 and 606 had the original grilles around the headlight and original headlights removed, and plated over using the vertical headlight in its place. Research: Neil Feldman

Thank you for a concise explanation. I'm assuming the older 244's were simply scrapped and not re-sold, huh? Shame.

Don't forget the #600. She was the first power-pack in 1971. Don't know what became of her, after her and the other 244-engined FA's, 601-604, 610 and 618, were relegated to stand-by status in 1985-86, and then sent off-property in 1988-on.

TBW: LIRR FA2 #600 was actually the ELEVENTH unit converted for push-pull service. (See the link to Steve Lynch's FA page on Page 1 of this topic - posted 11/21/2019) #600 was an "odd single" FA2 unit that was assigned the "open" number 600 in early 1974.

Built by ALCO October 1951-serial #79301-original NY Central 1102-Penn Central 1302 In service LIRR March 5, 1974 - Retired with ALCO 244 prime mover - to Western NY Railway Historical Society 1986 after 12 years of LIRR service.

ALCO FA2 Power units 601 to 606 (the original six) former L&N; 607 to 610 former Western Maryland 600 to 610 were FA2; 611 to 618 were FA1.

Good research of LIRR FA power unit history from Bob Losse/Extra 2200 South and Steve Lynch...MACTRAXX

One aspect of the diesel push-pull fleet that has not been mentioned in this thread was the 4 bar-generator cars, class BG72B, numbers 2101 thru 2104. These bar-generator cars allowed LIRR to operate 4 additional consists of push-pull cars without using a PowerPack or MP-15AC to provide HEP.

http://www.trainsarefun.com/lirr/odds_ ... or%20Cars

If you look at photos of the Power Packs, you will see that the number of trainline receptacles on the front end of the unit varies from 7 to 1. I am speculating that the 7 receptacles would be needed if the front end of the unit was facing the passenger cars (providing power thru the front end), while only 1 receptacle would be needed if the front end of the unit was not facing the passenger cars, with power being provided thru the rear end of the unit. At some point, someone decided that the the Power Packs would always be operated with the rear of the unit coupled to the passenger cars.

Thanks jhdeasy: Anyone with a good photo of the Power Packs, showing the number of trainline receptacles on the front end of the unit?

Oops, found one! Here we go:
#607 nose at Oyster Bay 1973 Photo/Archive: Richard Glueck

MIght folks indicate the function of the trainline receptacles, as I have numbered, thanks!

Its Pt. Jeff