M90>ZF22 & electric fan conversion

[Enterprise]

I have a 940 TDIC from 95 and it has the M90 trans with 1031 3.54 rear.
I know this might sound ridiculous but i want to convert it to auto. Mainly because i want the m90 for another car for D5252T swap, but also because i think the zf is much better combo with a d24.
So im wondering what all i should be worrying about while swapping and what all parts i should have.
We recently did swap from ZF>M46 in my friends car so i have almost everything but some small stuff was lost or given away, also i wasnt there for the whole time so some things i dont know in which order they were. So my main concern is the flexplate. Is there some spacer plates and shims? Can i reuse the manual flyeheel bolts? Do i need a pilot bushing?

Another project im working on is installing a electric 940 cooling fan and to control it i have a hose adapter for a thermoswitch.
Im used to putting it in the lower rad hose but these engines for some reason have the thermostat there��. I have a 80c thermostat and thermoswitch for the fan is 90c on 80c off. Where should i install it? If im thinking straight, cant put it in top hose because it gets hot long before the rest of the engine is hot.

[v8volvo]

Welcome to the board!

That plan doesn't sound ridiculous to me at all. I was never a fan of automatic transmissions until I started driving a 740 TD with D24T and ZF 4HP22. The ZF is a fantastic transmission that is a perfect match for the power delivery of the D24T. I like them with a manual but I like the automatic even more.

It sounds like you are starting with a good parts supply for this if you already took a ZF out of another car. As far as I remember (but can confirm this week for you), the flexplate goes right onto the crankshaft, no spacers or shims. However, there is a large "washer" carrying all of the flexplate-to-crank bolts, and the bolts for the flexplate are definitely shorter than the M/T flywheel bolts since the flexplate is thinner. You will want the correct length bolts. Greenbook manuals might even give the length spec for them, greenbooks are usually very good about that. You could probably source them from another vehicle such as an Audi, or order new hardware if needed. I'm not sure what would happen if you tried to use the bolts from the flywheel that are too long -- maybe it wouldn't matter much since they are open to the internals of the engine as I recall?

No pilot bushing needed with the automatic, in fact you will need to REMOVE the existing manual trans pilot bearing from the back of the crankshaft before assembling with the automatic, because the torque converter snout goes where the pilot bearing used to be (same outer diameter).

The small stuff won't be hard to figure out, the parts that really matter are things you presumably already have like trans mount, shift selector, driveshaft front half, and the trans/converter/flexplate. Some bellhousing bolts may be different length as well but you'll figure it out with them. Any questions you have along the way just ask here and we'll do our best to help.

Best place for a fan thermoswitch would be in the radiator itself, rather than in any hose. Factory Volvo location (as seen on the 1992+ cars that only had e-fans from the factory) is on the passenger side near the top. I would just use one of those if it were me. I am guessing they run similar temps but I think it says the settings on the switch.

You could also put it in the lower hose but I think you might want lower temp settings for running it there. It's OK that that's where the T-stat is. At any engine temp where you might possibly need the fan to come on, the T-stat will already be wide open so it won't affect anything. If the T-stat is closed, then that's because the engine is cool, thus no need for fan operation anyway.

That said, the factory mechanical viscous fan does work fine. They are noisy though.

[Enterprise]

Thank you!

It would be great if you could confirm, i will start the swap in two-three weeks from now.
Where can i find said manual?I suppose i could just take any 12.9 bolts just have them right lenght.

I should have everything else.Then i just have to figure out how to get reverse lights since i dont care about start immobilizer on the shifter. One of the leads need to be soldered to the car?

The M90 shouldnt have a pilot bearing so that makes it even easier But how sure are you there isnt a sleeve? Also i have a thick washer with a nipple on it facing one way for the flexplate, correct one?

Issue is i dont have a plug in my rad, not new or old to put the original switch in.
Sound like i should keep the stock visco even though ive bought everything for the electrical .
Thank you for the reply and i will surely need more help along the way...XD

[Enterprise]

Originally Posted by v8volvo

Welcome to the board!

That plan doesn't sound ridiculous to me at all. I was never a fan of automatic transmissions until I started driving a 740 TD with D24T and ZF 4HP22. The ZF is a fantastic transmission that is a perfect match for the power delivery of the D24T. I like them with a manual but I like the automatic even more.

It sounds like you are starting with a good parts supply for this if you already took a ZF out of another car. As far as I remember (but can confirm this week for you), the flexplate goes right onto the crankshaft, no spacers or shims. However, there is a large "washer" carrying all of the flexplate-to-crank bolts, and the bolts for the flexplate are definitely shorter than the M/T flywheel bolts since the flexplate is thinner. You will want the correct length bolts. Greenbook manuals might even give the length spec for them, greenbooks are usually very good about that. You could probably source them from another vehicle such as an Audi, or order new hardware if needed. I'm not sure what would happen if you tried to use the bolts from the flywheel that are too long -- maybe it wouldn't matter much since they are open to the internals of the engine as I recall?

No pilot bushing needed with the automatic, in fact you will need to REMOVE the existing manual trans pilot bearing from the back of the crankshaft before assembling with the automatic, because the torque converter snout goes where the pilot bearing used to be (same outer diameter).

The small stuff won't be hard to figure out, the parts that really matter are things you presumably already have like trans mount, shift selector, driveshaft front half, and the trans/converter/flexplate. Some bellhousing bolts may be different length as well but you'll figure it out with them. Any questions you have along the way just ask here and we'll do our best to help.

Best place for a fan thermoswitch would be in the radiator itself, rather than in any hose. Factory Volvo location (as seen on the 1992+ cars that only had e-fans from the factory) is on the passenger side near the top. I would just use one of those if it were me. I am guessing they run similar temps but I think it says the settings on the switch.

You could also put it in the lower hose but I think you might want lower temp settings for running it there. It's OK that that's where the T-stat is. At any engine temp where you might possibly need the fan to come on, the T-stat will already be wide open so it won't affect anything. If the T-stat is closed, then that's because the engine is cool, thus no need for fan operation anyway.

That said, the factory mechanical viscous fan does work fine. They are noisy though.

Did you ever have time to comfirm?

[v8volvo]

Apologies, I have been traveling away from my workshop for the past week. I will be home tomorrow and will look!

[Enterprise]

Originally Posted by v8volvo

Apologies, I have been traveling away from my workshop for the past week. I will be home tomorrow and will look!

Have you had time? Im soon going to start the swap and im only hung up on the flexplate and spacer thing.

[Enterprise]

Originally Posted by v8volvo

Apologies, I have been traveling away from my workshop for the past week. I will be home tomorrow and will look!

Hello. Have you had time lately? Im going to start the swap this weekend.

[v8volvo]

My apologies for the delay. I have had one of my colleagues out sick for the last two weeks in a business with only three employees, so we're down 33% of our workforce. I have been doing about 90-110 hours a week on the clock to try to cover for him, working 7 days a week. Not fun.

BUT I finally had time on Friday to get into the shed where my spare engines are stored!

Took a photo of the back side of an engine that came out of an automatic car, link here. Confirming that there is NO spacer between the crankshaft flange and the flexplate (drive plate). There is the "washer" ring that is used between the bolts and the flexplate, with its dimple facing outwards (towards transmission).

Hope this helps and again sorry I didn't have a chance to get this for you sooner, eating and sleeping have been enough of a challenge here this month.

Let us know how this goes and anything else we can help with!

[Enterprise]

Originally Posted by v8volvo

My apologies for the delay. I have had one of my colleagues out sick for the last two weeks in a business with only three employees, so we're down 33% of our workforce. I have been doing about 90-110 hours a week on the clock to try to cover for him, working 7 days a week. Not fun.

BUT I finally had time on Friday to get into the shed where my spare engines are stored!

Took a photo of the back side of an engine that came out of an automatic car, link here. Confirming that there is NO spacer between the crankshaft flange and the flexplate (drive plate). There is the "washer" ring that is used between the bolts and the flexplate, with its dimple facing outwards (towards transmission).

Hope this helps and again sorry I didn't have a chance to get this for you sooner, eating and sleeping have been enough of a challenge here this month.

Let us know how this goes and anything else we can help with!

Sounds stressful...but im sure the paycheck will sit nice
I found out that the mating surface of the torque converter and the mating surface of the block and trans shuold be 18mm. I measured at 17,2 which is within spec so yes no spacers.
Baked Beans Garage on YouTube has a video of a full rebuild where he showed this.

No worries, if i had known about your situation i wouldnt have asked. After those kinda hours the only thing on your mind is sleep. Thank you though.