Starter, Flex Plate Help

[zzfranczz]

I have a 1967 TH400 behind a BBC 427. I am installing a new MSD mini starter to replace my old worn out stock starter.

I have run into an issue where the starter gear is inserting to far into the ring gear (See link below). This currently has the .06" shim from MSd already in the starter and I am waiting for one more (06 shim) to come from MSD. I have measured the ring gear and it is about 3/8" thick so the next shim will only bring it in a 1/16th of an inch but not enough to be less than half way inserted into the ring gear. I need help fixing this or figuring out what is wrong so I can fix it.



I found flex plate shims but have never worked with them nor found a professional (called local shops) who has.

http://i1190.photobucket.com/albums/...sc4e9cfaa.jpeg

I also put in the stock starter and I have the same issue with the stock starter. Probably the reason it failed as well.

Can someone please provide some advice as to what I should do? Or should I proceed with the flex plate shims. I am thinking I will need a .90" or .125" shim in order to bring the starter gear into tolerance. I am not certain if this is a good idea to use such shims nor understand if there are going to be other ramifications if I do.

[zzfranczz]

Wow! Really disappointed with this community. :(

[Timmah]

Are looking to enter more depth of the thickest of the fly wheel or tooth to tooth clearance?

[zzfranczz]

Well in short I have come to the conclusion that I can not bring the starter to the MFG'ers specs. MSD promised (yet to be seen) to mail me shims to back it out .06 but that is still not enough to bring it into their tolerance. The other issue is that the gear to gear is at .120 which is well beyond the .02-.035 mfg'ers tolerance. I am guessing that the only way to get that down is to mill the starter or the block. I have since bought another brand of starter that has different tolerance standards but it is still out .02 on the gear to gear mesh. I was hoping that someone had experience with this and could provide insight or some guidance. I have talked to many professionals as well as a few mfg'ers and have gotten various responses, but really none seemed very knowledgeable. I have also chosen to replace the wiring harness and will test it once I get it in.

[camrat68]

The problem is that we're not quite sure what you're asking.

If you're standing on the passengers side of the car and looking at the flex plate edge-on, are you expecting the starter gear to move out and mesh with the ring gear on the flex plate evenly without one being left or right of the other? Every BBC I've worked on only engages to about 3/4 depth.

If you're standing at the back of the car looking at the flex plate and the distance between the starter gear tooth at the bottom between the ring gear teeth and flex plate is greater than .035 with no shims and no paint on the block mounting surface, then you would need to mill down the starter mount. Don't touch the block. If it's less than .025, then add shims to bring it farther away from the gear and block.

One thing to keep in mind is that the starter bolts correctly located the OEM starter but aftermarket starters have oversize mounting holes allowing huge differences in where it sits after you tighten the bolts. BBC's vibrate everything loose over time and mine tends to shift forward over time if torqued to spec. When I make it "Gorilla tight" I don't have any issues.

-Jim

[zzfranczz]

Hey Thanks Jim, I appreciate the help.

My issue is that the starter is engaging 100%+ and I need to shim it back. Each shim set gets me .06, so two gets me maybe a 1/8th of inch and that is beyond MSD's specification.

I figured out that I can not bring the MSD starter into their specifications so I ditched that and went with an IMI performance Products starter. I talked to Matt (562) 907-9400 and he helped me work out a solution to all of my possible issues. He was able to address my issues and was knowledgeable about the situation. Before that I called several prominent companies and I was very surprised with the responses that I received. I had more knowledge about the issues than they did it seemed. MSD said they would ship me a shim set but to date I have not received it. It would not have helped anyways since the starter would still be out of spec. Their starter is going to be returned. So in the end I bought a different starter, saved a few bucks, found a great retailer that has excellent support, and more importantly they were local to me.

[camrat68]

So is it up and working now?

That's good news about going local. MSD is a catalog order away and there you sit or you can drive across town and get it handled.

-Jim

[zzfranczz]

Working, not yet. Some family, RL things had to be taken care of first. I will get back to it in a few weeks but I do feel confident that it will work, just based on the measurements where before I felt that it was going to either bind or miss the gear. Finding someone local is a very big plus so if it does not work out he already has solutions where phoning the support of the big mfg'ers left me with a heartache. I also ended up having to replace the engine wiring harness and am waiting for parts to come in. Sadly I need a good auto parts store. I have driven many places only to find that most stores do not stock parts that I need, they all can order them. Finding it easier to use Amazon, just that every time I need a part it is another two days until it gets here. Once I get a ahead of things I will be better off. Thanks again for the help.