Nostalgia & History > speed recorder on sd9

On a sd9 that ran long hood forward on what 6 wheel truck and on what journal was the speed recorder?
thanks, paul

I believe it should be on #4 left as a long hood forward orientation.
Same really with a short hood lead, #3 right in that orientation.

thanks for your help, but does the speed recorder go on the truck under cab or the front truck?   What does #4 refer to?

Axles are counted from front to back, so long hood forward the lead axle at the end of the long hood (truck 1) is #1.
The axle under the cab is #4 (first axle of truck #2) in that scenario. Facing forward on the locomotive, left side is the fireman's side.

If the short hood was front, then that same speedo axle would be #3 (last axle on the #1 truck) and be on the right or enginners side.
 

Look for the letter:"F" stencilled on the frame by the stairwell on the end designated as the "Front" regardless of where the cab is. All engines have it. That's also what the switchmen go by when throwing signals for "go forward" or "go backward".

-LD



Edited 1 time(s). Last edit at 06/02/22 15:47 by LarryDoyle.

train1275 Wrote:
-------------------------------------------------------
> Axles are counted from front to back, so long hood
> forward the lead axle at the end of the long hood
> (truck 1) is #1.
> The axle under the cab is #4 (first axle of truck
> #2) in that scenario. Facing forward on the
> locomotive, left side is the fireman's side.
>
> If the short hood was front, then that same speedo
> axle would be #3 (last axle on the #1 truck) and
> be on the right or enginners side.

Your explanation is how individual railroads prefer to number their axles when the long hood is designated FRONT. However, EMC/EMD manufactured each and every GP/SD/F model with the number 1 traction motor/wheel-axle-gear set counted from the cab end (all electrical drawings are also so marked), regardless where the customer requested the "F" be mounted. Thus, on those railroads with "Long Hood Front" designations, the #1 traction motor/wheel-axle-gear set is still counted from the cab end of the unit. I can get VERY confusing on those railroads that had long hood front GPs and SDs, back the "old days".

Yes, I see your point !
Working wheel shop and drop table we always would go off the front - whatever end the "F" was at and go from there back 1-4 or 1-6. 
Also usually marked up with a soap stone "X" on the truck frame. Can't say I recall ever changing the wrong one. Having a crew put in the wrong replacement motor, then yes. Getting stupid and hooking up the leads wrong, then yes again ..... 
But what the "F",  yeah .... good point you make !  Luckily didn't have much of that to be an issue; GP-7's and GP-9's long hood front and I think worked on an ex N&W GP38AC we had at OmniTRAX Loveland once that was "backwards" and an old N&W SD45. I guess somehow we translated whatever needed to be from the prints and electricians to make sure we were getting the right one, especially if it was a motor issue. So then the question, as I never worked that much with "backwards" engines, was the TM Cut Out switch also so marked so that for the engineer or brakeman the #6 motor as they would perceive from the "F" was actually #1 ?  

HotWater Wrote:
-------------------------------------------------------
> train1275 Wrote:
> --------------------------------------------------
> -----
> > Axles are counted from front to back, so long
> hood
> > forward the lead axle at the end of the long
> hood
> > (truck 1) is #1.
> > The axle under the cab is #4 (first axle of
> truck
> > #2) in that scenario. Facing forward on the
> > locomotive, left side is the fireman's side.
> >
> > If the short hood was front, then that same
> speedo
> > axle would be #3 (last axle on the #1 truck)
> and
> > be on the right or enginners side.
>
> Your explanation is how individual railroads
> prefer to number their axles when the long hood is
> designated FRONT. However, EMC/EMD manufactured
> each and every GP/SD/F model with the number 1
> traction motor/wheel-axle-gear set counted from
> the cab end (all electrical drawings are also so
> marked), regardless where the customer requested
> the "F" be mounted. Thus, on those railroads with
> "Long Hood Front" designations, the #1 traction
> motor/wheel-axle-gear set is still counted from
> the cab end of the unit. I can get VERY confusing
> on those railroads that had long hood front GPs
> and SDs, back the "old days".



Edited 2 time(s). Last edit at 06/03/22 13:43 by train1275.