I got almost 300,000 miles out of my original starter on my 79 302. I bought a rebuilt unit and it chewed up my ring gear and starter teeth in less that a month. I noticed the housing was slightly different, the mounting ears were slightly thicker, but after reading the slip of paper in the box that said this unit may differ in appearance from the original, I went ahead and installed it. Now I have to pull the trans and replace the flexplate.
I've always checked (and shimed as required) GM starters, but never a Ford. It's easy on a Chevy since you can disable the starter and just operated the soleniod with a remote switch to check the gap. Since you can't do the same with a Ford, especially with the eng to trans spacer plate in the way, how do you check proper engagement?
Thanks.

 

No starter shims on Fords to my knowledge.
-Johnboy

 

This is a problem that has come up in the past. Here's a condensed technical bulletin concerning the issue:

"TECHNICAL BULLETIN:
Ford Starter Shims
ALERT: FORD STARTER DRIVE FAILURES
APPLICATION: All Ford Inline 6 & V-8 Engines, 1963 thru 1991
PROBLEM: Ford starters come in (either a core or alleged defective)
with the clutch retaining cap on the drive cut off on the front side, or worn from running against the flywheel.

REASON: The engine flywheel is floating. The crankshaft thrust bearing that keeps the crankshaft centered wears after about 60,000 miles, allowing the whole crankshaft and flywheel assembly to move toward the front of the engine.
THIS IS NOT THE FAULT OF THE STARTER:


SOLUTION: Ford Motor Company has made a shim to correct this problem. The part number was D6TZ-11N004. It was .090 thick and fit between the starter nose housing and the bell housing. thus backing the starter away from the ring gear. Ford has discontinued this shim."

I have one right here that I got from NAPA auto parts. Part Number is 655-1198

 

With the rebuilts I have had to add a washer to them since the castings were ground or just not right.

 

Thanks for the replies. My new flexplate should be in tomorrow so we'll see how it goes. Thanks for the part number for the shim. There's a NAPA right down the street, I'll pick one up if I have any problem.

 

The other possibility is that you have the wrong starter. There was a different depth of engagement for the standard trans vs. automatic trans.

A starter from an automatic engages deeper so if used on a standard trans. it will rub the one way drive housing against the flywheel and possibly fail to disengage.

A starter for a standard trans. installed with an automatic would not engage sufficiently, thus possibly stripping teeth. Perhaps this is your situation.

Compare the pinion gear protrusion of the new starter motor with your original to see if they are similar. Auto versions have the pinion protrude about a quarter inch if I remember right, the standard version close to flush.

What determines this depth of engagement is the starter snout, which is readily swapped on the starter motor, converting it to the other style.

 

Hello, I have a related problem on my 1988 F250 with automatic trans.
Gone thru 3 different starters not because they were bad, it is because
every starter I install on this truck makes a grinding noise when the
starter is turning the engine over.
I have closely looked at each starter and in and around the
bell housing but see no evidence of any metal or parts of the
starter drive coming off.
I am wondering if I should purchase the shim from NAPA and
would this quiet my noise starter problem?
I have owned dozens of Ford trucks over the years and was
not aware you could shim a Ford starter.
Thanks for any feedback.
1988 F250
1979 F100
1977 F150

 

I am having similar problems with Starter grinding. Been through 3 starters in the last year and already replaced my flex plate once. It just seems like the starter isn't engaging all the way by the looks of the teeth on the starter and flex plate. Would the shim help? I already have the shim.

 

I'd be inclined to investigate @Beanscoot 's thinking. #6 above. Maybe some useful info for your situation.
https://static.speedwaymotors.com/pdf/91067430.pdf