Will auto box fit to a manual engine?

christd · Post by **christd** » 21 Feb 2024, 15:15

Hello, I'm considering replacing my engine, and have found a replacement manual engine for my auto car. I do not plan on doing a manual swap (yet, at least), and wonder if anyone can tell me if the crank on the manual replacement engine will fit my auto box? Any other potential problems I should be aware of? My car is an early '94 (late '93) 850 Turbo auto, and replacement engine is from a crashed '96 T5 manual.

/ Christoffer

Post by **scot850** » 21 Feb 2024, 19:23

As many members have swapped autos to manuals, I would have thought the reverse was true?

Neil

christd · Post by **christd** » 21 Feb 2024, 22:35

scot850 wrote: ↑21 Feb 2024, 19:23 As many members have swapped autos to manuals, I would have thought the reverse was true?

That’s what I thought also. However, when I came across this post about a regular manual swap, the user says that:

«You can see here the metal 'bearing' circular hole in the centre of my auto's crank is bigger. Turns out this supports a protrusion from the torque convertor (presumably because of its additional weight). This is probably only important if you try to offer an auto box up to a crank from a manual as it won't fit! Going the other way is fortunately OK as nothing protrudes from the clutch through to this crank 'bearing'.»

Link to post: https://web.archive.org/web/20120825030 ... hp?t=71697

Attached a couple of photos.

: IMG_9256.jpeg (246.31 KiB) Viewed 342 times

: IMG_9255.jpeg (239.99 KiB) Viewed 342 times

Post by **scot850** » 22 Feb 2024, 08:28

Hm, sorry, but maybe it is just the angles that are different. They look the same apart from the auto looks like it may have a dowel pin the manual does not. Fitting a dowel pin would be a little challenging I guess, but not terrible.

Neil.

dikidera · Post by **dikidera** » 22 Feb 2024, 09:00

Think about it logically. The torque converter itself is ONLY bolted to the flywheel, it doesnt enter the hole in the crankshaft where the input shaft would normally enter on a manual. It's actually the TC that enters the input shaft of the AUTO box.

There is a very slight protrusion from the TC but I wonder if it's even that big or long to NOT enter whatever is there

I think as long as the TC can be bolted to the flywheel, it shouldn't be a problem. As it is the flywheel that actually holds the weight of the TC and not the inside hole of the crankshaft.

Post by **Chuck W** » 22 Feb 2024, 09:04

The sleeve can come out of the crank.

You can probably drive it out like a pilot bearing/bushing. (I don't remember if it's open behind the bushing or not)

I've packed the area behind the bushing with grease and then used a bolt about the same size as the ID of the bushing. Insert the bolt into the ID of the bushing and whack it with a hammer. The hydraulic force should push the bushing out.
I've also heard of people using bread for this purpose.

THIS POST shows the two separate bushings.

However, as mentioned above, I don't recall if that protrusion on the converter is long enough anyway.

(Also, that guy took lousy pictures with no actual information

)

dikidera · Post by **dikidera** » 22 Feb 2024, 09:16

It is to be noted however that it does appear on both images, that inside, the center hole is indeed different in both pictures. The auto hole does look larger. Though it could very well be an optical illusion due to angles and distances

In any case, I believe that protruding bit from the TC does not enter the whole, I think it would get close to the opening but not actually enter it.

Post by **scot850** » 22 Feb 2024, 10:22

I guess I am a visuals person and would have to see the issue physically to understand the difference.

Neil.

Post by **Chuck W** » 22 Feb 2024, 11:08

scot850 wrote: ↑22 Feb 2024, 10:22 I guess I am a visuals person and would have to see the issue physically to understand the difference.

Neil.

You can see the difference BARELY in the link I posted. The bushing that is in the end of the crank has a smaller ID on the manual ones and there are two different part numbers.

The only thing I can think of for why it's different is during clutch installation to locate the clutch disc. The manual trans input shaft is smaller than that locator nub on the torque converter. You need a smaller pilot guide to pass through the clutch disc to align things. You can do it without an alignment tool, but it does take more time.

The input of the transmission has no pilot on the end, so it's moot for installing the manual transmission after-the-fact.

I still can't remember if the torque converter nub protrudes far enough into the crank for it to make a difference. I'm guessing it does, as there are 2 distinct bushings.

christd · Post by **christd** » 22 Feb 2024, 15:43

Thank you for all you answers! I’m pretty confident now that it will fit. Apart from your answers, I have also talked with two Volvo mechanics today who also said it should fit. They even looked up the p/n for the cranks using VIN from both my car and the donor car, and they are identical.

Heading out to buy the new engine tomorrow, but I won’t swap it until the weather gets warmer. Crossing fingers that I won’t run into any problems. And if I do…all the more reason to get parts for a manual swap.