70 CTH L46 Flywheel and Starter

[Mike T.]

Just bought my 70 2 top convertible and the first project is to replace the flywheel and starter. The previous owner installed some custom high speed starter that tore up the ring gear.

I'm told that 2 different size flywheels exist. What size does the 350HP 4 speed call for?

What options do I have for the starter, or do I need to find an original 1108338? I'll find one eventually, but I want to get the car running.

Thanks.

[John H.]

Re: 70 CTH L46 Flywheel and Starter

I'm told that 2 different size flywheels exist. What size does the 350HP 4 speed call for?

What options do I have for the starter, or do I need to find an original 1108338? I'll find one eventually, but I want to get the car running.

Thanks.

Mike -

That combination originally had a 14" 168-tooth flywheel with an 11" clutch. Any rebuilt starter spec'd for your application will work fine until you find a "correct" one.

[Mike T.]

Re: 70 CTH L46 Flywheel and Starter

GEEZ! That was fast!! Thanks John. That's all I need to know!

[Terry M.]

Re: 70 CTH L46 Flywheel and Starter

Just bought my 70 2 top convertible and the first project is to replace the flywheel and starter. The previous owner installed some custom high speed starter that tore up the ring gear.

I'm told that 2 different size flywheels exist. What size does the 350HP 4 speed call for?

What options do I have for the starter, or do I need to find an original 1108338? I'll find one eventually, but I want to get the car running.

Thanks.

You may not need to replace the flywheel. The toothed ring is removable and reversible. Of course if the teeth on the ring are badly damaged, this trick will not work.

To remove the toothed ring: Heat the toothed ring all the way around the flywheel. If you support the flywheel face down on a short 2x4, or coffee can, the toothed ring will fall off when it expands enough from the heat. Quickly flip the flywheel over caution use gloves. The flywheel and ring will be HOT, flip over the ring and put it on the flywheel. If you work quickly enough, the ring will slip right over the flywheel and as it cools shrink into place.

It is best to use an oxy-acetylene torch with a rosebud tip. Of course everyone has one of these in their garage, right? A good automotive machine shop can do this for you for little money.

[Mike T.]

Re: 70 CTH L46 Flywheel and Starter

Cool idea. Thanks. I'll definitely give it a shot. Flywheels are expensive!

[Dennis D.]

Re: 70 CTH L46 Flywheel and Starter

I bought this from a guy a couple of years ago. He had bought out a parts garage and had a whole bunch of these nos. Think all are early 70 date. Even the solenoid is of the original style. I'll see if I have a contact for him

[Tom P.]

Re: 70 CTH L46 Flywheel and Starter

You may not need to replace the flywheel. The toothed ring is removable and reversible. Of course if the teeth on the ring are badly damaged, this trick will not work.

To remove the toothed ring: Heat the toothed ring all the way around the flywheel. If you support the flywheel face down on a short 2x4, or coffee can, the toothed ring will fall off when it expands enough from the heat. Quickly flip the flywheel over caution use gloves. The flywheel and ring will be HOT, flip over the ring and put it on the flywheel. If you work quickly enough, the ring will slip right over the flywheel and as it cools shrink into place.

It is best to use an oxy-acetylene torch with a rosebud tip. Of course everyone has one of these in their garage, right? A good automotive machine shop can do this for you for little money.

Naaaaaaaaaa, it's not necessary to go through all that.
Use a soft drift (such as brass) and a moderate hammer (2-3lb). Gently drive the ring gear off of the flywheel with the hammer and drift, working your way around the flywheel. THOROUGHTLY clean the sufrace where the ring was seated. Clean the ring gear. Place the ring gear in the over, heated to 500deg for 30-45min. Remove the ring gear (of course, use gloves) and place it back onto the flywheel (flipped over of course). It may or may not drop all the way down, so just use the hammer and drift to gently seat it all the way around.
That's all you gotta do. I can't count how many times I've done this.

[Tom P.]

Re: 70 CTH L46 Flywheel and Starter

The starter that you will need for a 168 teeth flywheel/621 style bell housing MUST have a cast iron nose with a staggered bolt pattern (specifically referring to a STOCK style GM Delco starter).
If you have a starter with an alum nose and staggered bolt pattern----------IT WILL NOT FIT INTO THE BULGE of a 621 style bell housing!