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Commander51
02-19-2005, 06:45 AM
My 51 Commander has a DG200 transmission. I've read several places that it is possible to push start the car with this tranny. Has anyone put this to the test?? If successful, how about some instructions? I assume you start in Neutral, then shift to Drive, but there's this old saying about "ass-u-me":D

Roscomacaw
02-19-2005, 08:40 AM
Yes, since it has a rear pump (alot of newer cars don't), it CAN be push started. Start out in neutral, turn the key on, have the car pushed to 15 or 20MPH and while at that speed - select Low or Drive. It should start.;)

Miscreant at large.

Peter in London
02-19-2005, 10:35 AM
That reminds me...... (warning of old story coming!)

We brought out '55 Champion automatic sedan back to the UK in 1957. We lived at the top of a hill outside Oxford. One day for some reason the battery was flat. We decided to start it coasting down the hill - quite long, straight and steep. I towed the car with our little Austin Mini (ordered withing hours of them being unveiled at Morris Garages, from whence the name MG, in Oxford) to the top of the hill, my father in the Stude - and down we went. At the bottom, on the totally level Oxford Southern by-pass, we came to a standstill and my father, exasperated, admitted that he'd forgotten to turn on the ignition! (He'd been our Atomic Energy Attache in DC.) So then I had to tow the Stude with the Mini on the level, which was quite a spectacle and quite an effort (for the Mini). The fastest we could manage was 30mph and at that speed, just, the engine started turning and the Stude started.

So it can be done!:)

Peter.

Sonny
02-19-2005, 09:38 PM
Great story Peter! Tooo funny! Just an added note, I've done it a couple of times, yes it works great. One thing though, the book says to drop it in gear at about 25, I did, (but you're right Peter), neither car started turning 'til about 30 mph.

Sonny
http://RacingStudebakers.com

wfsiew
05-09-2006, 08:56 PM
May i know what is the different of front pump and rear pump of Automatic Transmission?
Why the rear pump can push started of the vehicle, and how about the front pump, is this can push started too?

Thank you.

JDP
05-09-2006, 09:24 PM
Wow, never heard of dropping it in low or drive while being pushed, seems you'd go into the grill of the pushing car. I always waited until the push car dropped back. BTW, front pump only's can not be push started since the engine turns the front pump, not the driveshaft.

Studebaker On The Net http://stude.com
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64 Daytona HT
64 R2 4 speed Challenger
63 R2 4 speed GT Black
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63 Avanti
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53 Coupe

rockne10
05-09-2006, 09:28 PM
From the 1951 Automatic Drive Owner's Guide:

"PUSH STARTING If it becomes necessary to have your car pushed in order to start the engine, as in the case of a dead battery, turn ignition key on, set automatic choke by depressing and releasing accelerator pedal once, and place lever in N. The car may now be pushed and when you have reached 20 to 30 m.p.h. (32 to 48 km.p.h.), move the lever to D or L position. Do not tow the car to start the engine- your car may overtake the tow car."

These cars also came equipped with a printed sleeve that slipped over the driver's sun visor and provided basic operation instructions for these new automatics.

I have reproduced both the glovebox owner's guide and the visor sleeve if anyone's interested.

With the front and rear pumps in this transmission, it's possible to be running down the road in drive and slam it into reverse. The car will slow down, come to a stop and start going backwards. I wouldn't recommend it for fun but it was designed to enable you to rock back and forth out of snow or mud.

Owner's guide recommends check oil level every 1,000 miles; drain and refill every 15,000 miles.

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wfsiew
05-09-2006, 11:21 PM
What is the reasons cause the rear pump can push start while the front pump cannot?

rockne10
05-09-2006, 11:38 PM
Motion from the rear wheels, through the driveshaft, in to the rear of the transmission must then be carried through the transmission to get the engine to turn over to jumpstart. Without a rear pump the hydraulics in an automatic transmission would not flow through the transmission valve body. Front trans input would not turn, nor would crankshaft, ergo pistons, valves, distributor, et. al. No spark, no jump.

hank63
05-10-2006, 02:20 AM
Also, the rear pump was smaller than the front one (at least in Torque Flites). I was told that's why the push-speed had be close to 30 mph before the engine would turn over.
/H

wfsiew
05-10-2006, 03:36 AM
Could u explain clearly how does the "output shaft pull the input shaft" in order to get turn to turbine, impeller & engine as well,Pls?


quote:Originally posted by rockne10

Motion from the rear wheels, through the driveshaft, in to the rear of the transmission must then be carried through the transmission to get the engine to turn over to jumpstart. Without a rear pump the hydraulics in an automatic transmission would not flow through the transmission valve body. Front trans input would not turn, nor would crankshaft, ergo pistons, valves, distributor, et. al. No spark, no jump.

gordr
05-10-2006, 06:34 AM
[quote]Originally posted by wfsiew

Could u explain clearly how does the "output shaft pull the input shaft" in order to get turn to turbine, impeller & engine as well,Pls?

Well, I'll try.

The automatic drive has a torque convertor, and a 3 speed hydraulically-controlled transmission. Gear changes in the transmission are effected by hydraulic pressure applied to servos (simply devices that turn hydraulic force into mechanical action) which apply the bands or clutch packs. Bands are used to brake some elements of the planetary gearsets, and clutch packs are used to couple other elements together. There is also a direct drive clutch in the torque convertor that locks it up for economical highway cruising.

In any case, no hydraulic pressure source, no drive. The primary source of hydraulic pressure is the front pump, which is driven by the engine by a pair of tangs on the outer sleeve of the torque convertor shaft. The front pump runs at all times when the engine is running. The secondary source of hydraulic pressure is the rear pump, which is driven by the output shaft of the transmission, and which delivers pressure whenever the car is in forward motion. The main reason for having a rear pump, in my understanding, was to provide a pressure "signal" to the valve body that was speed-related, in order that gear changes could be properly controlled. Nevertheless, the rear pump will, at sufficient road speeds, develop enough pressure to apply the servos to engage the drive through the gears. The torque convertor will act as a fluid coupling when driven on the over-run, and apply enought torque to the engine to spin it over so it can start. I don't know if the direct-drive clutch in the torque convertor will apply under push-start conditions, but it is not necessary that it apply in order for the car to start. (Other brands of auto transmissions which lacked the direct-drive clutch, but which DID have a rear pump, could also be push-started.)

Hope this helps.

Gord Richmond, within Weasel range of the Alberta Badlands

wfsiew
05-10-2006, 08:35 PM
GOOD! Clearly explaination,Thanks for your infomation about the push start by the rear pump...ANyway, i'll will appreaciate to your info about this and hope can useful in future!




quote:Originally posted by gordr

[quote]Originally posted by wfsiew

Could u explain clearly how does the "output shaft pull the input shaft" in order to get turn to turbine, impeller & engine as well,Pls?

Well, I'll try.

The automatic drive has a torque convertor, and a 3 speed hydraulically-controlled transmission. Gear changes in the transmission are effected by hydraulic pressure applied to servos (simply devices that turn hydraulic force into mechanical action) which apply the bands or clutch packs. Bands are used to brake some elements of the planetary gearsets, and clutch packs are used to couple other elements together. There is also a direct drive clutch in the torque convertor that locks it up for economical highway cruising.

In any case, no hydraulic pressure source, no drive. The primary source of hydraulic pressure is the front pump, which is driven by the engine by a pair of tangs on the outer sleeve of the torque convertor shaft. The front pump runs at all times when the engine is running. The secondary source of hydraulic pressure is the rear pump, which is driven by the output shaft of the transmission, and which delivers pressure whenever the car is in forward motion. The main reason for having a rear pump, in my understanding, was to provide a pressure "signal" to the valve body that was speed-related, in order that gear changes could be properly controlled. Nevertheless, the rear pump will, at sufficient road speeds, develop enough pressure to apply the servos to engage the drive through the gears. The torque convertor will act as a fluid coupling when driven on the over-run, and apply enought torque to the engine to spin it over so it can start. I don't know if the direct-drive clutch in the torque convertor will apply under push-start conditions, but it is not necessary that it apply in order for the car to start. (Other brands of auto transmissions which lacked the direct-drive clutch, but which DID have a rear pump, could also be push-started.)

Hope this helps.

Gord Richmond, within Weasel range of the Alberta Badlands

MarkC
05-11-2006, 02:47 PM
gordr's explanation is very good, but here's a little more...

In the early days of automatics (starting in the 40's), push starts were a design consideration since engines and electrical systems mainly batteries) were not as developed or reliable as they are now. As he stated, the front pump is the main source of hydraulic pressure for the transmission and is crankshaft driven. The rear pump was supplemental in nature, driveshaft driven, and provided line pressure that could be utilized in the event the engine wasnít running (ie: push start). As technology (and reliability) improved (60ís and up), rear pumps disappeared. Not everyone felt this was advantageous, but complexity and costs were reduced as part of the plan.

Before sophisticated electronic controls began to appear in automatics (70ís-80ís) and operation was still fully hydraulic, the shift points were (mainly) controlled by a driveshaft driven governor that modulated the line pressure. Basically, main line pressure (high) was a constant when the engine was running (due to the front pump) and was fed to both the governor and the valve body. In the valve body, the line pressure was applied to one side of the shift valve(s). Governor pressure was applied to the other side. Governor pressure was minimal with the vehicle stopped, and increased with vehicle speed. As the vehicle accelerated, the governor would apply more pressure to the shift valve until, at the design speed, the governor and line pressure were equal on both sides of the valve. At this point, spring pressure would move the valve and line pressure was applied to the appropriate servo to affect the shift. A throttle pressure valve was usually employed to override the governor, delaying pressure buildup, to delay shifts in the event the throttle was floored. I know this is a vast simplification and there have been many variations through the years. But, you get the general idea. And, itís amazing how well this worked for several decades.

Take care,

MarkC


MarkC, 64 Y8
Working in Spokane, WA

65cruiser
05-11-2006, 03:16 PM
Kind of unrelated, but from what I'm reading about the rear pump this tells me that you could easily flat tow one of these with a towbar. You can't do that with many cars of today without benefit of an external electric tranny pump.

Hmm, maybe I should think about a Studebaker dinghy behind my motorhome[:p]

________________________
Mark Anderson
1965 Cruiser
http://home.alltel.net/anderm

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rockne10
05-11-2006, 07:24 PM
I flat towed my 51 about 60 miles when I bought it. Back then I didn't know any better. I'm glad the Borg Warner engineers envisioned my stupidity.:D

studegary
05-12-2006, 01:35 PM
I can't even come up with an estimate of how many Studebakers I have flat towed with a tow bar. I have never experienced a transmission problem due to this. Other problems, yes, but not transmission problems.

On the subject of push starting - I can recall many instances of push starting cars, including automatics, with Studebakers, but I never recall having a Studebaker that I had to get a push start for.

Gary L.
1954 Commander Starliner (restomod)
1959 DeLuxe pickup (restomod)

MikeW
05-13-2006, 01:56 PM
It was rather common in my circle to push start automatics back in the 1950s. I did this many times and seemed to always have something go wrong. So take care! My most memorable push story was when we pushed my Commander to start it. My brother was the designated Stude driver and we pushed it with a 1955 Ford Pickup. It was our habit to get the car up to about 30 and then to back off with the push vehicle while the car to be started would be shifted into L and would start. This time we pushed and backed off but my brother did not have the key on. The car slowed to a stop of course but on a set of RR tracks. We just pulled up in the truck when the flashing lights went on. Thank goodness there were three of us. We jumped out and hand pushed the car off the tracks before a fast freight zoomed past. Scared the heck out of me.


Mike
www.packardhawk.com

imported_n/a
05-14-2006, 10:33 AM
The early transmssions could not only be push started, but towed long distances without it being necessary to remove the drivshaft. The aluminum-case transmissions Gm and others were using from the 60's on didn't have the rear pump. So, they not only couldn't be push started, they weren't even supposed to be towed more than 20-30 miles with the driveshaft in place, due to insufficient lubrication. This is the engine wasn't running and turning the (front) pump.