63 starter issue

[Michael G.]

The starter on my 63 L84 was a 67 model, p/n 1107320. It was squealing on some starts because the rear bushing was failing. I replaced it with a properly dated 1107242, rebuilt by a respected restorer. The first time I went to start it, the gears did not mesh properly, with the expected grinding noise.

Does anyone know if there is a "normal" cause for this? Is the flywheel for a 63 different from a 67? Any help would be appreciated. Thanks,

Mike

[Joe L.]

Re: 63 starter issue

The starter on my 63 L84 was a 67 model, p/n 1107320. It was squealing on some starts because the rear bushing was failing. I replaced it with a properly dated 1107242, rebuilt by a respected restorer. The first time I went to start it, the gears did not mesh properly, with the expected grinding noise.

Does anyone know if there is a "normal" cause for this? Is the flywheel for a 63 different from a 67? Any help would be appreciated. Thanks,

Mike

Michael-----


The 1963-68 327 flywheels and ring gears were identical. So, I don't think that's your problem, assuming that you have a correct flywheel installed.

Your starter may require shimming to correct improper alignment between the starter drive gear and ring gear. Procedures for this have been discussed on this board and should be found in the archives.

By the way, you did use the proper knurled shank bolts to retain the starter, didn't you?

You can purchase shims at your local auto supply store in the carded "HELP!" or "Motormite" sections.

[Paul J.]

Re: 63 starter issue

Mike:

Joe's right. Sometimes starters require shimming. I was looking for my flywheel picture to attach but I've lost it. It's in the archives somewhere. It's the one with the center ripped out of the flywheel, a direct result of severe misalignment.

Something may be different because of the rebuild, but I'll have bow to the rebuilders to discuss that. There's some discussion of this in the archives.

Paul

[Michael G.]

Re: 63 starter issue

Thanks Joe,

I used the proper bolts and even tightened them correctly. That the part I'd better get right, considering what I did for GM for all those years

I'll read about shimming in the archives. That's what I get for trying to use the proper, dated, parts

Mike

[Michael G.]

Re: 63 starter issue

OK, I've pulled the new starter out of the car. I noted a very significant difference between the old and new one: On the old starter (which still works), the gear is located .18 inch farther toward the rear of the shaft (closer to contact with the ring gear) than the gear on the new starter. Knowing nothing about starters, this would seem to be quite a large difference. Anybody know?

Thanks, Mike

[Timothy B.]

Re: 63 starter issue

Michael,

I don't think that is a problem, check the mounting height of the aluminum case compared to the old starter. In the rebuild process it may have been broched to be flat and need a shim or two because the pinion gear is meshing in the valley of the ring gear.

[Michael H.]

Re: 63 starter issue

Michael,

I don't think that is a problem, check the mounting height of the aluminum case compared to the old starter. In the rebuild process it may have been broched to be flat and need a shim or two because the pinion gear is meshing in the valley of the ring gear.

I think Tim is correct. Unless the starter drive gear is making contact with the flywheel when the engineis running, I don't think the depth of the gear in the housing is an issue.

I don't remember for sure, but if the nose of the 320 starter looks the same as the nose on the 242, and the 242 worked properly, I would probably switch noses.

[Michael G.]

Re: 63 starter issue

Tim,

As close as I can measure it with calipers, its the same distance on both cases. I didn't even have to move the slide.

The noses look different, so I can't make the switch.

Mike

[Joe L.]

Re: 63 starter issue

Tim,

As close as I can measure it with calipers, its the same distance on both cases. I didn't even have to move the slide.

The noses look different, so I can't make the switch.

Mike

Mike-----


Can you post photos of the two noses? If not, how are the two different? As long as both noses are aluminum and "long bolt, short bolt" mounting, they should be functionally interchangeable.

[Michael G.]

Re: 63 starter issue

Joe,

Here are some photos. The two noses are probably interchangeable, but I'd rather not mess with it at this point, because the vendor will still stand by it if there is a problem. I'm trying to figure out whether there is something wrong with the rebuilt unit, so I can send it back.

Mike

[Joe L.]

Re: 63 starter issue

Joe,

Here are some photos. The two noses are probably interchangeable, but I'd rather not mess with it at this point, because the vendor will still stand by it if there is a problem. I'm trying to figure out whether there is something wrong with the rebuilt unit, so I can send it back.

Mike

Mike-----

Yes, those two noses should be functionally interchangeable, so there's no necessity to change the noses. However, the old nose, apparently, worked without shimming and, presumably, it would work without shimming if transferred to the new starter. That would be the only reason for transferring it.

I agree with you, though, as I wouldn't want to transfer it and sacrifice the warranty on the rebuilt unit. I don't think the rebuilt unit is defective; I just think that shimming will be required. Most starter noses (the part of the starter that affects the requirement for shimming) don't require shimming. For whatever reason, a few do. Your is, apparently, one of them.

I noted the starter nose bushing on the old starter appears to be "exiting" the nose. The design of the nose on the rebuilt starter precludes this sort of happening. This is one of the design changes to the aluminum noses that occurred over time. I don't think this style nose was originally used in 1963, not that anyone would ever be able to tell with the starter installed on the car.

[Michael G.]

Re: 63 starter issue

You guys obviously know more about this than I do, but I'm trying to get the whole shimming thing straight in my head:

If the mounting surface determines the relationship of the starter gear to the ring gear, and, since I measured the distance from the mounting surface to the center shaft on the two starters and found it to be essentially the same, I'm trying to picture what a shim is going to do to improve things, (unless the gears are different, which seems unlikely).

It may work, but being an engineer, I need to understand how it works. Does anyone have a good handle on how that works? Thanks for your patience..

Mike

[Joe L.]

Re: 63 starter issue

You guys obviously know more about this than I do, but I'm trying to get the whole shimming thing straight in my head:

If the mounting surface determines the relationship of the starter gear to the ring gear, and, since I measured the distance from the mounting surface to the center shaft on the two starters and found it to be essentially the same, I'm trying to picture what a shim is going to do to improve things, (unless the gears are different, which seems unlikely).

It may work, but being an engineer, I need to understand how it works. Does anyone have a good handle on how that works? Thanks for your patience..

Mike

Mike------

It's extremely difficult to precisely measure the nose dimensions to determine if one is identical to the other with respect to the dimension affecting the need for shimming. If one is different by only a few thousandths that can be enough to require shimming.

As far as the starter drives (gears) go, all of the 63+ (and, even earlier, as I recall) are functionally interchangeable. In fact, there was no difference between the drives for 153 and 168 tooth ring gears. However, it's possible that there was enough manufacturing dimensional tolerance in the drives to affect the need for shimming of the starter. I doubt it, but I'd say it's possible.

[Michael H.]

Re: 63 starter issue

The first time I went to start it, the gears did not mesh properly, with the expected grinding noise.

Mike

Mike,

Just so I understand this correctly, does the starter actually crank the engine but makes a grinding/gear mesh sound, or does the drive grind against the teeth of the flywheel but not actually engage?

It may just be the way the light is shining on in your picture but the end of the teeth on the new/242 starter gear appear to be blunt, or ground off flat. Each tooth should be pointed at the end.

[Michael G.]

Re: 63 starter issue

Michael,

The engine was at TDC when I tried to start it. The starter/ring gear made a brief grinding sound (I know this sound well from my younger days), then I switched off the key. Upon inspection, the engine was still at TDC, it had not moved, so I would say the drive gear grinds against the ring gear and does not engage.

I'll try shimming tomorrow and let you guys know what happens.

Thanks,

Mike