Bendix Spring Question

[Joe K]

On a former thread I mentioned that some had reported that "reverse wound" bendix springs had been seen. I've heard of this but have no idea of application or even if they are Model A.

And until recently it really wasn't a concern to me.

I was recently gifted a box of 8 springs. Five of these appear "reverse wound." and three of these appear "correct wound" according to the five Model A starter/bendix example "spares" I have here.

The way to tell reverse from correct spring is to look at the spring as you look at "threads." Yunno - righty-tighty - lefty-loosey. If the spring mimics a right handed screw it is INCORRECT for the Model A (reverse wound)

If the spring mimics a left handed screw it is CORRECT for the Model A (correct wound)

The correct wound springs all appear to be the A-11375-C spring which is a little "beefier" (2-1/16 OD) than the earlier A-11375-DR (1-13/16) You can tell the difference in weight between these two. The incorrect wound springs appear to be a mix of these two types.

Kind of a question as perhaps I already have my answer (i.e. which springs should I keep) but what of those reverse wound springs - can they be used on a Model A? Mere mechanics says they can - the failure mode may be different.

And does anyone know of the application for these reverse bendix springs? One imagines an engine which operates "reverse" compared to the Model A.

Bendix have been used for MANY applications/engines over the years.

Joe K

 

[Keith True]

Lots of farm machinery has the starters mounted to the rear,with the bendix facing forward.John Deere,Farmall,and AC among others.After working on machinery for over 40 years I have mixed a few wrong bendix parts in the my A stuff.Spirals go the opposite way too.

 

[Kurt in NJ]

model T

 

[stevests]

My Model T & A springs are wound the same direction only T has a 5/16" bolts as did the early A - later A is 3/8".

 

[nkaminar]

The springs are wound in reverse to confuse and frustrate the Model A owner.

 

[Joe K]

The springs did come from a Model T/Model A owner (owns both)

Dimensionally they conform to the dimensions shown in the Service Manual (i.e. 1-13/16 OD or 2-1/16 OD) I didn't notice any difference in the size of the "eyes."

As Keith says - possibly for an engine with the starter mounted to the rear of the flywheel? I'm not sure of the Model T configuration.

Joe K

 

[katy]

model T

Ditto

Model T starter is behind the flywheel, one lifts the floorboards to get at it.

 

[nkaminar]

Maybe some had the starter behind the flywheel and that would explain the opposite wound spring, but all the Model T engines I have seen had the starter in the same location as the Model A, in front of the flywheel. At the back is a cover that is removed to get to the Bendix drive. The Bendix has to be removed first to get the starter out of the engine.

The very early Model T engine had the starter in front of the car in the form of a bent piece of steel rod.

 

[Joe K]

I look through the picture book "From Here to Obscurity" (about the Model T) and I see only pictures of engines with the starter in front of the flywheel similar to the Model A.

Electric starter began about 1918?

The former owner of these springs has a 1924 Model T.

The Model T Service Bulletin picture of the starter motor/bendix (May 15, 1919) shows a spring wound as the Model A spring is wound.

Joe K

 

[nkaminar]

Motors on combines run in reverse. I wonder if any of the diamond engines that were built for combines ran in reverse. Probably not, knowing Ford.