Adjusting pitch on RobbMc 3001 starter

[428Marauder]

So, I currently have my 65 Mercury Park Lane at a mechanic to get some things done. Just had a different mechanic instal a new starter on a different car and the one that was removed is a RobbMc 3001 by all appearances. “Identical to the new one”, said the mechanic. It was a good and working starter, I’m trying to solve a heat soak issue on that car and the new 3001 did not change the issue. So, I gave the older (but working) starter with the instructions to the other mechanic. He says the pitch isn’t adjustable and it’s not engaging with the flywheel. He installed both the starter and the flywheel that is on there (184 tooth) so I have to assume he knows what he’s talking about but also there’s no reason, from what I understand, that this starter (which is sold to work with a 184 tooth flywheel) shouldn’t work. He says this starter can’t be shimmed. Thought I’d pass this by you guys since I know a lot of you use these starters to see if anything jumps out at you immediately. Thanks.

[HarleyJack17]

Is the block plate installed? There should not be any shimming needed and Rob Mc Stuff fits good and as the FE Block plate is what aligns the starter.

[Katz427]

I'm not sure, so just my experience.  Many years back, I had an old Ford 390, that had a 184 tooth flexplate, and the teeth were different,  so the starter many times would just "zing". Turns out it was an aftermarket flex plate, I replaced it with a genuine Ford part, "(from the local dealer) flex plate, and then the starter was happy. The flexplate and starter engaged, no trouble.

[6667fan]

https://www.robbmcperformance.com/products/fordat_starter.html

Does your unit have the optional pinion support?

[428Marauder]

Not sure if it has the optional pinion thing. Mechanic is saying that the pitch or the backlash is not adjustable and they have spoken with RobbMc and they don’t have any solutions. It’s baffling to me that this was a working starter on a 427 and is impossible to install on a 428.

[69ramair]

I am having the same problem with a Powermaster 9506M starter . I have less thank 2 dozen starts on it pulled it out and found that there is play in the shaft of the starter just wiggling it withe my fingers I’m sure that the play is compounded when torquing on the ring gear causing it to not mesh properly. Might be an idea to ask your mechanic if he checked for that