Definitive Fix for Starter Misalignment

[Tom Wells]

Jahred,

I'm not real good at diagnosing stuff like this without seeing the parts. Heck, I'm not real good at diagnosing....

The function of the shim, as I understand it, it is not to control the depth of engagement but to allow the starter teeth to retract away from the flywheel enough to completely disengage. If they don't completely disengage, metal will be ground away, usually with some considerable sound effects Don't ask me how I know this.

As to the auto/stick flywheel differences, I'd suggest you contact that starter vendor (or one similar) and ask that question.

With that much metal disturbed (if I'm visualizing the pinion gear's damage correctly) there may be some damage to the teeth on the flywheel. You may wish to inspect there before you try another starter.

Ouch!

Tom

[cwmcobra]

Jahred,

I'm also having some difficulty visualizing your wear pattern, but perhaps I can help with the right starter. I'm on a business trip in Asia now, but before I left I had a chance to "dry install" my flywheel and RobbMc starter and check clearances. I checked the mesh of the pinion with the ring gear, gap between the end of the pinion and the face of the flywheel and backlash of the pinion in the ring gear. All are within the specs recommended by Robb. Here's what I can tell you....assuming you are using the block plate with the Lakewood bell, the registration diameter in the block plate is in the correct place to locate the starter to the flywheel. What you need to look for is a starter with the pinion centered in the registration diameter. Most that I have found (including the Ford Racing mini starter) have at least some offset, which affects the radial alignment of the pinion to the ring gear. The stock Ford starters have the pinion centered in the registration diameter. So does the RobbMc starter. The other critical dimension is the gap between the end of the pinion and the flywheel face. When I ordered the starter from Robb, I did some dimensional checking and found that with my flywheel (Ford Racing made by McLeod) we had the starter assembled with a short pinion to maintain the correct gap. The Ford Racing flywheel has a recess machined on the side mounted to the crankshaft which locates the ring gear closer to the starter pinion. It sounds to me like you have too little gap in your setup and need to fix that. I highly recommend you visit Robb's website (www.robbmcperformance.com) and study his installation instructions for the Ford BB starter to get the recommended gap. His starter is a bit pricey, but well worth it in quality and confidence in fit and function. Oh, and by the way, his starter, like the stock Ford starters uses a 9-tooth pinion. The Summit starter I have uses an 11 tooth pinion and, surprisingly, the Ford Racing mini starter uses a 10-tooth gear.

Hope this helps. Even if you don't want to buy a starter from Robb, I suggest you use his installation instructions as a guide. Good luck!

Chuck

[cwmcobra]

I've assembled the RobbMc starter an checked clearances with the ring gear on the flywheel. It all checks out correctly. Here's the RobbMc starter:



Here's the gap between the flywheel face and the end of the starter pinion:



Finally, here's the tooth engagement of the starter pinion in the new ring gear:



See the paper clip in the picture. This confirms about 0.030" gap between the end of the pinion tooth and the root of the ring gear tooth. I also measured the backlash of the gear set to be about 0.035". According to Robb, these are all within expected ranges for proper pinion to ring gear engagement.

The engine is not back in the car yet. When it is, I'll post my comments on the function of the starter.

Chuck

[cwmcobra]

The engine is back in the Cobra and I've had numerous opportunities to use the new starter under various conditions. It's worked flawlessly. The solenoid location is infinitely variable and I rotated it around behind the starter body away from the heat of the headers. When it's started after a hot soak, it spins just like when it was cold. The only time it struggled was when I was experimenting with spark timing and got it a bit too far advanced. Right now I'm running 24 degrees initial advance, which is up from 16 that most recommend, and the starter seems to spin the motor with ease. Based on the detailed analysis that Robb did, working with me on identifying the potential sources of mismatch between the starter pinion and the flywheel ring gear, I'm totally confident that I won't have any more broken teeth on the flywheel. The RobbMc starter is a quality piece that functions very well. If you can make a stock Ford starter fit in your application, it should work fine as well, but if, like most of us, you have space constraints for starter installation, I can't recommend Robb's starter any higher.

I've attached a picture of the starter installed on the engine.



Chuck

[ByronRACE]

If you think you're going to simply ovalize the bottom bolt hole and pivot the starter over closer or further from the ring gear when using a FORD F250 starter, don't overlook the fact that it has a locating ring that mates with the bellhousing. It's not so easy. I've been there.

Someone needs to make a 460 starter that (1) does not have this locating ring and (2) has a simple adjuster that pivots the starter as-needed and (3) has an inspection hole so you can see the starter gear and ring gear with the starter installed (without removing the transmission). This would be an obvious hot seller...this problem is widespread.

If such a starter existed, all you'd do is back the adjustment nut off, install it, spin the adjusting bolt until it's tight, then back it off X turns...and tighten the main mounting bolts. Someone please make this so I don't have to.

Byron

P.S. If anyone cares, drilling/modifying your lakewood bellhousing voids the SFI certification Also, the root-cause of this problem (according to and old timer at Tilton) is that Lakewood used an FE flyweel when mocking up their bellhousing design and has yet to fix it.

[cwmcobra]

Byron,

After discussing with several starter specialists, I can't agree with you more. When I had my engine out of the car, I was able to do a lot of fitment tests. As luck would have it, I have a stock "block plate" for a 460 that I bolted up with the Lakewood block plate. Doing this, I confirmed that the registration diameter for for the starter in the Lakewood block plate is precisely in the same position as the one in the stock plate. The stock starter has the pinion centrally located in the registration diameter, as does the starter I bought from RobbMc. Any starter that has an offset pinion is likely to have problems. Both the Summit and Ford Racing starters had some offset. The stock starter also has 9 pinion teeth, as does Robb's starter. The pinion on the Summit Protorque starter has 11 teeth. And, surprisingly, the mini starter I bought from Ford Racing has 10 teeth. Seems that nothing matches the stock alignment geometry except a stock starter or the RobbMc starter. I agree with your suggestion for an easily adjustable starter with a viewing window in the bellhousing. But, since no one has marketed this yet, my best approach was to confirm that what I have is geometrically correctly aligned. And, for those who can fit a stock Ford truck starter in their applications, an even lower cost option is available.

No question, trying to improve the alignment of the starter by relocating the mounting holes is a non-functional, unreliable solution.

Chuck

[ByronRACE]

I'm going to order to RobbMc starter on Monday.

I'll report to the group if this solves my problem as well.

Right now I'm running a very molested Ford F250 starter that was modified to move the starter gear closer to the ring gear. It works, but I did a poor job of the needed modifications (I was frustrated, and in a hurry). I was planning on buying another F250 starter, weld up the bottom hole, reposition it, and re-machine the locating ring and starter hole. Why? Because I think the ovalized hole solution eventually will cause ring gear failure when the starter finds its way back to the original position. I just don't want that risk.

If this RobbMc starter solves it, I'll be a real happy guy. If it doesn't, I'll have one for sale.

Byron