Topic: Removing CB750 engine help.

[cookindaddy]

I wrote earlier for help with a top end oil leak on my 1978 CB750K and got some great advice here. Torquing the top cover bolts to spec helped a bit, but it still leaks oil pretty badly. Unless I carry oil and another pair of pants, I can't ride it anymore until this is fixed. One person wrote that I could maybe lift the cover enough to get the old gasket cleaned out and get the new one in place, but I think that would be very hard to do well, especially at the back near the carbs.

So it looks as if I must remove the engine to take off the engine cover to replace the top gasket or whatever else is leaking above the #1 plug. I have the cover gasket and I have read and re-read my Clymers about removing the engine. It doesn't seem too bad at all until "lift the rear of the engine and remove it from the right side of the bike". Sounds easy huh? The engine weighs about 175 lbs? Yesterday a motorcycle savy friend came over to puzzle on this with me. He hadn't done a CB750 either so I thought I'd keep researching as we got ready to do this.

I am looking for help on how to do this last step. Do you need four strong guys to lift and jiggle the engine out? Is there a lift or jig that one can use to help with the removal and re-insertion? Lots of people have done this to work on their engines I'm sure. This will be my first.

I've looked here in the FAQs and searched for messages. Can someone steer me or advise about this critical step 

[KeithB]

I did one by myself, once  and would suggest 2 people.
Get the bike on the centre stand and get a milk crate on the right side of the bike.
Once all the bolts and oil lines, oil filter cover, carbs and electrical are off, you can slide the engine out the right side.
Now it does take a bit of tilting and tweaking and some colourful language but it will come out.

[troppo]

The trick that seems to be fairly popular is lay the bike on its side and lift the frame off the engine.
I stripped my bike down to frame engine and forks and front wheel yesterday and removed the engine this way tonight, one man no strain just some fancy wiggling..
you could do it without stripping the bike down that far  but you would probably need another bloke to help lift.

[kvallelunga]

Removing the exhaust studs for cylinders 1-3 will also aid immensely in adding the fractional inches required to do this easily. Removing the wires,brackets, carbs is far more cumbersome than getting the engine out. 

[lordmoonpie]

The trick that seems to be fairly popular is lay the bike on its side and lift the frame off the engine.
I stripped my bike down to frame engine and forks and front wheel yesterday and removed the engine this way tonight, one man no strain just some fancy wiggling..
you could do it without stripping the bike down that far  but you would probably need another bloke to help lift.

Yup - that's the way I did it - out and in! Put lots of rags, towels etc on the floor and lean the whole bike over on this. I did so with just one pair of bolts left holding the engine in. Take those out and then wriggle the frame over the engine. I reversed it to get it back in and it worked just great.

It's a very big lump to do by yourself and lifting it out so this is a good compromise...

[andy750]

As others have said, take the exhuast studs out and also take the small tab off at the back of the engine - the one the carb overflow tubes are supposed to go through. And if you can take the valve breather cover off as well (the little triangular cover on top of the engine). With these 3 things done (and all bolts removed) the engine should slide out (to the right) in a matter of seconds...with one person on the left and the other on the right to pull it through. It helps to lift the rear of the engine up a little, front goes down a tad and then slide out.

Good luck!

cheers
Andy

[cookindaddy]

Wow.

Excellent suggestions all and Thank You!

I can say that I am actually looking forward now to this job.
It might be a few days until I can get to it and I will be sure that I have some sturdy helpers.
I must admit that the laying it on its side approach appeals to me.

Another person I talked to this morning suggested that with the front bolts removed, and with the appropriate other things removed that the engine would pivot down enough on the back bolts to provide clearance enough at the top to get the engine cover off.

The local shop I talked to this morning also said that there was not easy way to do this but brute force lifting/hauling the engine out the right side. They quoted 8 hours to do the job at $60 per hour plus parts.

It's time to learn how to do this myself.

And THANKS once again to all of you for answering.

[ZanVooden]

When I pulled out my engine on my 78K, I did it with the help of a buddy. we took all the hangers out, and he held the bike stable and did some lifting, I did most of the lifting. It came out fairly easy, a little jockeying around to get past the exhaust studs.

We were able to completely disconnect everything and lift the engine out in about 2 hours, neither of us ever having done it before. I had the clymers manual as well as the manuals you can print off this site. 
8 hours seems ridiculous.

Good luck, now its time for me to put my engine back in.

[shoemanII]

i raise the bike fully up on a bike jack, then suspend the rear of the engine via a rope and the front of the engine via a come-along.  i lower the floor jack ever so slightly until the rope and come-along are tight.  remove engine bolts then lower a tad more.  i then use the come-along to incrementaly adjust the pitch of the engine up/down as needed.  slides right out, no help needed.   

just prior to re-install, i grind 1/8inch off the "fins" off the right-side mounting lugs.  re-install is then a breeze. 

will be doing this juggling act in a few months, just to look around in my new bikes' engine, re-torque the head bolts and check the cam lobes.  good luck!
bobp   

[KingCustomCycles.com]

http://kingcustomcycles.com/howitisdone.html under how it is done I have a sling I use.  I can do an engine removal in 30 minutes.  Replace it in 15.

[bunghole]

I did the "lie the bike on its side" maneuver as well to get the engine out.  I think I will rig up something similar to what King suggested, or something like in this thread:

http://forums.sohc4.net/index.php?topic=38654.0

You can get a chain hoist at Harbor Freight for pretty cheap.

[bunghole]

http://kingcustomcycles.com/howitisdone.html under how it is done I have a sling I use.  I can do an engine removal in 30 minutes.  Replace it in 15.

What kind of straps did you use and how did you secure them to that bar?  I'd be afraid they would tear.

[KingCustomCycles.com]

Straps are from a ratchet strap rated at 500 pounds.  They are bolted to the bar with 1/4 -20 bolts.  Burn/melt the holes in the strap for strength.  The bar is thick wall hollow tube in 4130 Aircraft but that is just what I had lying around.  The key is to lift and still be able to jockey into position out the right side.  Rigid bars and brackets are tempting but were not flexible enough.  The engine goes in, and then rotates into position, which is the real kicker from a tool design standpoint. I am still looking at garage sales for a set of weights so I can stop using my next SOHC rebuild as a counterweight. Lifting that big chunk straight up and out is a nightmare.  I used to lay the bike on its side prior to the bar idea.  I just do too many engine swaps a year to not have it go well. 

[cafe750]

I just swapped motors in my '75 750F, by my lonesome. I covered up the frame and got everything unbolted. Then while laying on top of the frame, I tipped up the rear of the engine, and lifted/rocked it out, and set it on a milk crate. I had the other engine sitting on another crate, slid that one into position next to the bike, and reversed the procedure. Motor out and in, 10 minutes, with just me, and no special tools...It can be done...

[cookindaddy]

cafe750:
I'm reading this and I am impressed (I originally asked the question).
I want to ask you: what kept your engine from falling down after you undid the bolts?
You had a floor jack or something underneath it so it did not fall downward when you undid the last bolt?
Then you lay across the top and maneuvered it out?
Thanks a lot.
It sounds like your back is a lot stronger than mine.
But then you are younger.....
Thanks
George

[cafe750]

George-
It'll sit in the frame without any fasteners, fairly close to its final location. She can't fall out the bottom, if that's your worry. I also found it easier to remove the oil tank/lines, just to get them out of the way. Hope this helps!
-Peter