converting a 75 240 to a B230- mounting issues

never mind all the electrical and fuel stuff, this thread is about the hard parts.

i have the complete engine mounts from a B230. the engine is sitting in the bay with them all bolted down properly as i type this. so far so good.

i have a few front half shafts for the drive line- i'm not entirely sure which is the right one, but i'm pretty sure i have all the possible options at my disposal. unfortunately, i can't get to that part yet.

i'm having a problem bolting the cross member to he underside of the car.

i replaced the B20/M40 combo with a B230f/M46. i used the steel trans-side mount that came on the m46, and the square rubber mount that came off the M40 (as i just replaced it recently.) the metal ears on the rubber mount have tangs that wrap around the steel mount on the trans, and they bolted together perfectly. so far so good...right until i tried to bolt that whole mess to the frame rails...they don't seem to line up with any of the holes on their own.

basically i'm wondering if the rubber M46 mount is physically longer than the M40 mount, as that could potentially explain the misalignment. i need to know if i need to get a new mount, or get a cross member from an M46 car.

thanks in advance.

You need the round rubber mount for the M46. I've done a few 1975 swaps, and been there.

ok awesome, thanks!

when I had an m46 in my car, on 2 of the holes would line up for the x-member, IIRC

Sell the 75 to Carl Jardevall in California. he's sold his Evobitchi and he NEEDS A 75 to build .
Then just grab another of any year.

Sell the 75 to Carl Jardevall in California. he's sold his Evobitchi and he NEEDS A 75 to build .
Then just grab another of any year.

andysbeta said:

You need the round rubber mount for the M46. I've done a few 1975 swaps, and been there.

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got the round mount, put it on, same problem. feels bad, man. in fact the round mount and the old square one were the exact same thickness. even with just one bolt in one side, i can't force the x-member far enough over to line up with any of the holes on the other side- the front hole on the x-member is halfway between the two holes i want to be in.

my AW71 crossmember isnt lining up with two of the four bolt holes. Gonna have to just run two out of 4.

The fuel pump mounting bracket holes arent there either.

ZVOLV said:

my AW71 crossmember isnt lining up with two of the four bolt holes. Gonna have to just run two out of 4.

The fuel pump mounting bracket holes arent there either.

Click to expand...

interesting. mine has a couple of holes to mount the pump by the gas tank but that's it.

my x-member was from an M40, and i compared it side by side with one from... i forget, either an M46 or a bw-35, and they were identical. i ended up doing like you said, bolting it up all cockeyed with 2 bolts...then i discovered that my trans has the smaller size output flange, and the one on my drive shaft is the large one.

I've had this happen when coming to mount the crossmember. I just start one bolt in one side, leave it a bit loose.. then goto the other side and pry the crossmember to line up with the hole and use a cordless impact gun to run the bolt in. I've put in a b230ft into one 1975 245 w/ m46 and used the later style crossmember and it went in.. took a bit of a fight as mentioned but it went in. Another 1976 245 w/ b23f and M46 with the original crossmember (that is the same as the automatic style) went in just the same way too.. It is just the nature of the beast.

If this isn't the case, take a pic and post it? I'd be interested to see what your problem is. I'm on 1975 245 #3 now and I can take some pics of its original crossmember and mounting holes. Seems to be the early 240's have alot of variances in manufacture.

ZVOLV said:

my AW71 crossmember isnt lining up with two of the four bolt holes. Gonna have to just run two out of 4.

The fuel pump mounting bracket holes arent there either.

Click to expand...

Just running 2 of the holes sounds a bit sketchy if your going to put any real power through it. How hard is it to drill and tap some more holes?

Dont know bout the 75, but the later cars without the extra rear holes...ive drilled them open, then drilled 1" holes further back in the frame rail so i can fish washers and nuts into the rails to get those 2 rear bolts in....definatly sketchy with only 2, u really need 4

Mark

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volvorod85 said:

Dont know bout the 75, but the later cars without the extra rear holes...ive drilled them open, then drilled 1" holes further back in the frame rail so i can fish washers and nuts into the rails to get those 2 rear bolts in....definatly sketchy with only 2, u really need 4

Mark

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That is what I might have to do for the tranny crossmember AND the LH fuel pump. The rear of the fuel pump bracket mounts to where a bracket for the brake lines mounts, but the two front holes to mount the fuel pump definitely aren't there.

The 1975 244 we have also has this same problem for the fuel pump AND tranny. For the fuel pump the PO drilled thru the floor and put 10" long threaded rods and mounted the fuel pump all crooked...I just kind of wanna rig a single intank pump system at this point.

swiggy said:

Just running 2 of the holes sounds a bit sketchy if your going to put any real power through it. How hard is it to drill and tap some more holes?

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real power? yeah that'll be the day.

as for drilling and tapping more holes, the rails aren't thick enough; they have nuts welded to the inside for a reason. i'll figure something out, and i'll take pics of it. hopefully saturday.

andysbeta said:

If this isn't the case, take a pic and post it? I'd be interested to see what your problem is. I'm on 1975 245 #3 now and I can take some pics of its original crossmember and mounting holes. Seems to be the early 240's have alot of variances in manufacture.

Click to expand...

the biggest problem is the place i was trying to do all this, but i'm towing it to my shop saturday and will have a lot of the weekend to button this up. i'll bring a couple of mounts and an extra large massaging tool.

The plasma cutter and a MIG welder will solve all!

Have you stitched in the engine bay? I like how even in a car with no power a stiffer chassis makes the suspension work better. Seat of the pants better. Get it to not twist and you won't hear the windshield moving every time you pull into a driveway. The engine will come back out in ten minutes! Do it!