Topic: Newbie needs help taking out engine

[ateamal11]

Hi guys,
    I'm a newbie to the SOHC scene and am in need of desperate help.  I just bought a 1978 cb 750K that doesn't run!  I'm a bit of a DIY'r so i've decided to bob it.  Alright, so thus far i've pretty much taken this entire thing apart in about 4 hours.  I'm trying to get it down to the frame so that I can chop and bob it.  Things have been going well up until this point.  I'm at the stage where the engine is ready to be removed but i'm having problems with the "rear engine hanger lower bolt".  I've taken out all of the other engine bolts but this thing will not budge.  I've put a jack under the front end of the engine to make sure it is not sagging but i'm still having problems taking it off.  The nut just seems to be stuck onto the bolt.  I've tried to blast it with a chemical to make it easier but it hasn't.  The rod moves when i turn the nut and don't restrict the bolt, but when I try to remove the nut and hold the bolt I just can't seem to move it.  I'm not a huge guy, 6'2'' 200lbs, but i'm pretty sure i'm putting more then enough force that should be required.  Am I doing something wrong?  Any suggestions for this newbie?

[rickmoore24]

Use a breaker bar and you're done. Just make sure you dont round off the nut and/or bolt.

[hondaface75]

forgive me for asking a dumb question, but maybe there is a nut or bolt on the other side also spinning?

[MCRider]

Wouldn't the "rear engine hanger lower bolt" be the one with the footpegs on it? If so, its a nut on both ends. A wrench on both ends and one of the nuts will turn. The weight of the engine should hold the bolt enough to get at least one of the nuts off then drive it out? Am I missing something?

[ateamal11]

This hagner bolt does also hold on the foot pegs.  The entire bolt moves freely when use the wrench on either the head of the bolt or on nut that holds it in place on right side (alternator and brake side of the bike).   Unfortunately, when i put a socket wrench on the nut side, and a wrench on the bolt side (with my friend holding the other end) I get no movement.  Any little movement I do get is accompanied by a loud sound (i'm sorry but I can't describe it).  It doesn't sound like anything is breaking, just that this nut doesn't want to budge.  I've also rotated a wrench on the bolt (shifter side) so that it won't move.  I've then attempted to use my socket wrench on the opposite side to remove the nut.  I'll try using a breaker and let you guys know how it goes.  I really do appreciate the help from those that have responded.  I'm going to be adding pictures once I get the engine out.  I'm a true newbie who's attempting an entire repuild of the engine and tranny.  Then I'm going to put it all back together into a bobber.  I'm hoping you guys will like the pics, updates, and fiasco that is sure to ensue. 

[MCRider]

We ALWAYS like pics, especially of problems. As mentioned that bolt should be nutted on both ends and one should turn. If its as you describe, it has been changed and all bets are off.

Me, I'd get medieval on its a-- and get a bigger wrench. YOu can always rplace it with a piece of all thread or go to your local salvage yard.

[Spikeybike]

Me, I'd get medieval on its a-- and get a bigger wrench. YOu can always rplace it with a piece of all thread or go to your local salvage yard.

+1 ...  get a cheater bar/ breaker bar    ...might try some heat as well

[rickmoore24]

Yeah, yeah, HEAT! Fire Fire Fire!!! With a breaker bar, it doesnt stand a chance!.........either that or hack an end off and get a replacement.

[ateamal11]

   Good news guys!...The f*ing bolt is off.  I used the mother of all breaker-bars.  This thing is a 7foot long pipe laying in the garage of the house I just moved in.  I'll take pics of this thing and the ridiculous length.  I appreciate the suggestions of fire and getting medieval on it's a**.  I'm sure i'll take these helpful suggestions sometime soon.  About the pictures, i'll be putting them up very soon.  My next task is to actually take the engine out.  Once that is done i'll have to do some serious searing on the forum for how to rebuild an engine. 

Here's a brief history of the bike and what I know of it.  I bought this bike  a couple of weeks ago for $250.  It's a 1978 Cb 750.  The bike wasn't in terrible shape but wasn't anything really to look at.  The guy I bought it from tried to start it for me but it didn't run.  He said there was an engine coil problem as far as he knows but i don't really trust that.  I bought it b/c the frame looked straight and I really just want to bob it so itwas good enough for me.  I don't know if anything on it really works.  The engine, tranny, brakes, forks, all of of it could be sh+* for all i know.  I've got tons of time and like to try to do this stuff on my own so I figured i'd just start hacking away.  I'm a poor law student but $250 seemed to be a steal for hours of fun and frustration for the summer.  So yeah that's the story thus far.  Let me know what you guys think and if you know of a good logical order, or what I should be doing please drop a line.  Thanks guys

[rickmoore24]

Theres no real right or wrong place to start. I suppose it really depends on the shape of the old girl when you started and your plans for the bike. Since you're yanking the motor I'm guessing your going with the frame off rebuild along with the bobbing. Good news though, you just overcame your first hurdle that required a forum question posting. Moving on! If there are no real problems with the motor, more often than not a legit carb cleaning will get the bike running pretty well. Oh and just my .02 cents; when you get there, I suggest you clean and paint your motor. I didn't and sometimes it bugs me a little as I sceam down the freeway.