Starter Motor differences

[Sundowner]

I expect that you folk already know all this, but for me its all new and exiting stuff......

My Sprints starter motor packed it in the other day. The local auto electrician told me it needed another armature. I had a quick look around down here and found nothing so I bought a re-built starter from Robsport.
When it arrived I spent a gazillion hours trying to get the thing to fit, but couldn't. The bolt holes lined up with the studs OK but it just wouldn't go into place. Just to see if I was the problem, I tried the old starter and it fitted easily.......phew.
When it arrived I had noticed some small differences in the casting around the rear of the starter and in desperation I dismantled both the new and the old units, attached the old casting to the new unit and fitted it up OK. The thing is now in the car and operating as it should.
I understand that some Sprints used bolts to secure the starters and some, like mine, had studs and nuts. Could this be the the reason for the difference in casting?
The photos attached show those differences, with the biggest one being the slightly smaller hole for the ring gear and its slightly different angle. You'll also notice how the solenoid is mounted differently too.

Anyway, as I mentioned above, the car is now operating again, but I'd like to know what was going on here....if you know, that is.

Cheers,
Rob

[sprint95m]

It was only a small number of early Sprints that used bolts, the starter remained unchanged for the change to studs.


Early Sprint starters didn't have a spacer between it and the engine backplate but when the starter was redesigned
later a spacer was used.
So if you had the spacer I suspect that the new starter would have been okay?


I am surprised you couldn't source an armature locally because I thought these were common to Lucas starters of that era
across a range of cars.




Ian.

[xvivalve]

They sent you a TR7 starter; look at the difference in flange casting shape to the RHS of your photo's, it is very subtle

[Mad Mart]

Yep, I had a similar problem a few years ago. The flange on the TR7? starter clashes with a protrusion on the engine block. I just Dremeled a notch out of the starter flange.

[Sundowner]

Thanks Gents.
Rob