[corbs280z]

Hey guys, I’m trying to pull the engine out of my ‘75 280 right now, and I cannot for the life of me get the engine and tranny separated. Does the crank have to be in a certain position? I am honestly completely lost, any input or help would be appreciated.

 

[mailnome]

It’s the nature of the beast…cast iron, aluminum, and time. Generally though it’s corrosion around the dowel pins that make it hard. You can try soaking it with some penetrating oil (WD40, PBBlaster) and smacking areas you can get to with a rubber mallet and repeat if you want to be gentle. If you don’t still have the trans bolts loosely in, put a couple back in a couple turns to keep it from completely coming off while you are working on it.

If it’s still in the car you can raise and lower the engine on and back off the mounts a few (or a bunch) to change the tension on it and “try” to shake it around while down and up and/or pry if you want to.

Prying. That’s generally my next step after quick frustration with the gentle approach. Just be careful and mind what you’re prying against. A nice set of pry bars are handy but screwdrivers can be used. I try to use two side by side to spread the stress. I’ve have also driven a 2” putty knife in between them to get it started. Sometimes they (transmissions in general) can be a real pain to separate.


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[Dave Datsun Tech.]

Have someone hold the clutch pedal down while you tap around the bell housing with a hammer.

 

[pilgrim]

And using a plastic or other non-metal hammer isn't a bad idea...although it may not be sufficient.

 

[Joemolf]

Have someone hold the clutch pedal down while you tap around the bell housing with a hammer.

Correct the disk could have frozen to the flywheel. Forget wd40 get some kroil. Spray all seems let it sit overnight. Patients and good luck you will get there

 

[corbs280z]

It’s the nature of the beast…cast iron, aluminum, and time. Generally though it’s corrosion around the dowel pins that make it hard. You can try soaking it with some penetrating oil (WD40, PBBlaster) and smacking areas you can get to with a rubber mallet and repeat if you want to be gentle. If you don’t still have the trans bolts loosely in, put a couple back in a couple turns to keep it from completely coming off while you are working on it.

If it’s still in the car you can raise and lower the engine on and back off the mounts a few (or a bunch) to change the tension on it and “try” to shake it around while down and up and/or pry if you want to.

Prying. That’s generally my next step after quick frustration with the gentle approach. Just be careful and mind what you’re prying against. A nice set of pry bars are handy but screwdrivers can be used. I try to use two side by side to spread the stress. I’ve have also driven a 2” putty knife in between them to get it started. Sometimes they (transmissions in general) can be a real pain to separate.


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I have the dowel Pins out already and there is about an inch of space between the block and bell housing now, but I still cannot get the engine out of the car. It feels like the transmission and the engine are still attached somehow, cause I’ll hit it with a soft mallet, use a crowbar, and for the life of me cannot get them to properly separated

 

[Dave Datsun Tech.]

Can you get one of those flex head ratchet box wrenches in through the starter hole and unbolt the clutch pressure plate?

 

[Dave M]

sounds like the input shaft is bound up, need to get the rear of the engine and front of the trans supported before attempting to pull. I would support the back of the engine pan with a block of wood and a small jack, then have the trans on a trans jack, try to neutralize the two and then shake the trans back. If its just hanging on the input shaft you will be in for a drop of something when it does release. The fan may end up in the rad if you are not careful.

 

[corbs280z]

sounds like the input shaft is bound up, need to get the rear of the engine and front of the trans supported before attempting to pull. I would support the back of the engine pan with a block of wood and a small jack, then have the trans on a trans jack, try to neutralize the two and then shake the trans back. If its just hanging on the input shaft you will be in for a drop of something when it does release. The fan may end up in the rad if you are not careful.

This is probably it, thank you. And I’ve taken the fan and fan clutch off as well as the radiator already, so I’m all good.

 

[pilgrim]

The only connection between those units is the splines on the front transmission shaft where they slide through the clutch disc. The pressure plate and clutch disc create no connection between engine and transmission. I suppose the pilot bearing might get stuck to the front of the tranny shaft, but I've not seen it happen. I think @Dave M is right on target. Any angle between the engine and trans could cause a rusty front shaft to bind where the shaft slides through the clutch disc. I can't imagine it won't break loose if you can get the engine and trans in a straight line and pry the bell housing away from the engine block.