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Oil pan removal - '81 CB750K

JMC

CB750 Enthusiast
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Hello riders,

I can't get the oil pan off of the engine. I'm removing it to make dropping the engine easier. I've taken out all of the bolts. What am I missing? Did the previous owner use RVT or something on the gasket?

Any help is appreciated. Looking forward to getting this engine out of the frame and really giving it a clean up/rebuild.

JM
 

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You shouldn't have to take the pan off to pull the engine out. Double check, then triple check that you have all the bolts out, then you can carefully pry it off.
 
I removed the oil pan before removing the engine, it gave me flat surfaces to set the engine on before wheeling it out on a furniture dolly. Make sure all of the bolts are out, give it some sideways whacks with a rubber hammer or a hammer and wooden block. Nothing else holding it but the bolts around the perimeter of it.
 
I removed the oil pan before removing the engine, it gave me flat surfaces to set the engine on before wheeling it out on a furniture dolly. Make sure all of the bolts are out, give it some sideways whacks with a rubber hammer or a hammer and wooden block. Nothing else holding it but the bolts around the perimeter of it.
I'm counting 14 bolts removed. Does that sound right?
 
Agreed. Any recommendations on safely prying it open?
yes, under no circumstances should you force anything BETWEEN the mating surfaces. this can cause deformation of the metal and prevent you from ever sealing the pan again. around the perimeter of the pan you should find 2 or 3 areas of extra aluminum bossed out by bolt holes. these are surfaces intended for prying on. use prybars or a large flathead screw driver to pry on these area and it should pop off. I recommend applying constant pressure and slowly increase the pressure until it peels off. do not strike it with anything or you risk damaging the pan.
 

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For an update, what I did was remove the "subframe" which allowed me to gain better access to those oil pan "lips".
Then I just took a piece of wood and rubber mallet and started tapping. It came off pretty easily after that, just needed the right leverage/angle.

On another note, I believe removing the subframe section will make it significantly easier to remove the engine. I'll post about that once it's done.
There's a great youtube video on it and it's much more logical than other ways I've seen to remove the CB750 when you don't have a professional shop.
 

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I took my engine out that way. I slid a furniture dolly with 1/2" inch plywood under the engine, placed blocks of wood between the engine and dolly, removed the mounting bolts, raised the engine another 1 1/2 inches in the front to clear the remaining frame and wheeled it out on the dolly. Installed it the same way. All of this with the bike on its center stand. One person job until it was time to flip the motor over.
 
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Excellent. I've seen so many videos where the guy is taking a stud, strapping it to the engine, and then awkwardly lifting/twisting it out.
I have a motorcycle jack, so it should be a one man job and relatively safe.
 
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