240 Worth it to swap bell housing on M46?

I am in the middle of swapping an older M46 into my 91 245 automatic. The bell housing on my M46 does not have a cut out or 'thin spot' for the crank sensor. My original plan was to replace the bell housing with one that did have the cut out. However, I was reading that each bell housing is shimmed individually to the transmission.

Do you think it's worth swapping it or should I just cut into the bell housing I have?

Also I wanted to remove the bell housing to replace the front seal. I took out the 4 bolts and the snap ring at the base of this sleeve.



Does the sleeve pull out or does the bell housing slip over it?

Make a cardboard template and trace it on bell housing. Cut it with angle grinder. It's not hard to do. I did it recently.

dandeluca said:

I am in the middle of swapping an older M46 into my 91 245 automatic. The bell housing on my M46 does not have a cut out or 'thin spot' for the crank sensor. My original plan was to replace the bell housing with one that did have the cut out. However, I was reading that each bell housing is shimmed individually to the transmission.

Do you think it's worth swapping it or should I just cut into the bell housing I have?

Also I wanted to remove the bell housing to replace the front seal. I took out the 4 bolts and the snap ring at the base of this sleeve.

Does the sleeve pull out or does the bell housing slip over it?

Click to expand...

The shim on the output bearing are for that particular transmission, and the bell housings are consistently machined so they will swap as long as you use the shim that came with it or one of equal thickness.

4 choices of shim thicknesses iirc.

Mid cycle bellhousings have a thin knockout section that's easy to break out and clean up the lip with a rattail file.

Edit:

Due to the quality of available seals I'd leave it alone unless it's leaking.

I see. If I keep the spacer from my transmission I should be able to swap the bell housing.



I assume the ring that is hanging near the bearing is the spacer we have been discussing?

dandeluca said:

I see. If I keep the spacer from my transmission I should be able to swap the bell housing.

I assume the ring that is hanging near the bearing is the spacer we have been discussing?

Click to expand...

Yes it is, don't lose it or mix it up with other parts.

Have fun cleaning off the old gasket and good luck with the new seal.

From my conversion to LH2.4 (click for bigger):
- You'll need to notch your transmission to clear the CPS - if not pre-notched, you can cut out and file the CPS notch in the older bell housing. Not as strong as the later housing with the factory cutout, but OK for my needs:

From my conversion to LH2.4 (click for bigger):
- You'll need to notch your transmission to clear the CPS - if not pre-notched, you can cut out and file the CPS notch in the older bell housing.

Click to expand...

Is the CPS notch simply centered between those two bolt holes? Hopefully I will be able to purchase a updated bell housing locally but its good to have options.

I decided to pull the bell housing I had and replace the seal since my throwout bearing sleeve really needs rust removal and a good cleaning. Hopefully I will be able to purchase a updated bell housing locally but its good to have options. I also could not be sure of the condition of the old seal. Scraping 40 year old gasket should keep me busy for a while.

dandeluca said:

Is the CPS notch simply centered between those two bolt holes?

Click to expand...

Yes.

Is the engine still in the car? If not, you can mark where the CPS is on the engine, remove the CPS, mate up engine&tranny, and transfer marks to tranny. Or use a paper template to transfer the CPS outline. The cutout doesn't need to be exact, just a big enough to clear the CPS, with a little extra space around the bolts so that you can remove the CPS in place.