740 m46 swap questions

I just picked up an m46 and flywheel today for dirt cheap and I'm hoping to swap it. I've never actually swapped a transmission before. the guy who sold me it didn't know what car it was from, but my guess is it's from an early 240 (cable driven speedo and no crank trigger cutout.) I know I'll need a different shifter cage than whats on it to fit in my 740.

I have read a few write ups about it but I think mine is different than those. I am swapping a Regina car (to my knowledge, this hasn't been recorded anywhere on the internet.) I know this isn't ideal but the flywheel is from a carbureted engine (I think.) I'll have the timing marks machined into it.

anyways, the output shaft flange has 4 bolts instead of 3, as I've seen most places. would this bolt up to an auto driveshaft? I also have an aw71 that I "measured" (with my hand) and the flange does seem to be the same size. the auto driveshafts are longer, would it be possible to cut down the driveshaft somehow?

also, how would I make it so the clutch is hydraulic instead of cable actuated? do I just need a different fork? (and the hydraulic stuff, obviously..)

also also, how could I plug up the speedo cable hole? or can I just cut the cable and run it like that?

it would be more practical to go out and buy a different 740 with a manual in it already, but I'd like to try swapping this one.

if I'm wrong with any of the things I said, feel free to correct me. like I said, I've never swapped a transmission before.

edit: I forgot to add one more question I had, the m46 seems to have a different crossmember too. however, a Volvo parts distributor has a diagram that seems to depict an adapter to use the automatic crossmember (see pic.) it's no. 5 in the diagram.

https://linksharing.samsungcloud.com/jdImZ91nouVG

Your link picture shows the two different crossmembers and trans mounts with brackets for the back of the trans. No adapters in that picture. You are going to need more 740 specific parts like the shifter cage and shifter linkage. A clutch pedal, the crossmember and associated parts like in your picture to mount to the trans.

I would just use the cable clutch setup unless of course the only clutch pedal you can find is for the hydraulic setup. You are correct in that you need a different clutch fork and you may need to drill and tap the support boss for the clutch arm since the tranny is from a cable clutch car. For the driveshaft you can have one shortened at a shop but I would try to find the front half of the driveshaft so it's a bolt on. You need the front half from a pre 88 M46 car. You may also need to swap the flange on the trans if the bolt holes are incorrect.

The parts aren't getting any easier to find nowadays. So keep planning and searching for the parts. In the meantime look around for a manual trans car to buy cause it's a lot easier than a swap.

BTW I forgot the big caveat. The flywheel has it's own special trigger holes for Rex/Regina. There is a flywheel for that application but it's very rare. There was a guy selling one in the for sale section. If you are going to have a flywheel drilled I would try to have that done with a flat flywheel. The lighter weight makes for a faster revving engine.

I have a 740 / M46 shift cage and the longer shift rod.

PM me with interest.

Edit:

1983 700 M46 diesel's short prop had a 240 style 4 bolt output flange but due to the D24 engine's length it may not work on a 4 cal gasser, idk.

Redwood Chair said:

I have a 740 / M46 shift cage and the longer shift rod.

PM me with interest.

Edit:

1983 700 M46 diesel's short prop had a 240 style 4 bolt output flange but due to the D24 engine's length it may not work on a 4 cal gasser, idk.

Click to expand...

A diesel M46 won't work without changing to a gas engine bell housing. I have seen both 4 bolt and 3 bolt flange gas 740 M46 transmissions. No idea why both were made.

OP, I have the correct cross member that I will sell. Send me a PM if you want it. Thanks.

If your 240 M46 has this style early shift cage it's basically incompatible with a 700 since the mounting points are different and the 700 cage will not bolt on.