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Discussion Starter · #1 ·
Hi Guys,

I recently got a 76 CJ360T (free!) that had been sitting 15 years in a barn. Supposedly it ran when put away and he drained the fuel. It actually looked pretty nice under the inch of accumulated dust!

First thing I did was to pull the sparkplugs and give a good squirt in each cylinder. Since the kick start lever is broken I pulled the left side cover and turned the crank via the magneto/flywheel. It seemed to be stuck but finally broke free and now the motor rotates.

Questions:
#1 When I plug up the spark plug holes with my thumbs only the left one seems to have compression.... The right does suck a little but does not seem to blow my thumb out much at all. How bad is this? What do you think the chances are if I try to fire it up on the one good cylinder it will loosen up what ever is leaking in the bad one?

#2 When rotating via the magneto/flywheel using a ratchet on the center bolt (no spark plugs installed) how smoothly should it rotate? There still is some resistance at some points but it defiantly does spin completely around.

Thanks
 

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1) Beg, borrow or steal a compression gauge. You really need to know what kind of numbers you're dealing with before putting any time into getting it running.

2) You'll probably need a top end rebuild. These motors aren't very difficult to work on, it'll be fun.
 

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Hey, welcome aboard Red!

Well, you'll get recommendations all over the map. From those who would tear it down right off the bat, no questions asked, to those (myself) who would take a chance...

The way I look at it, you're not WASTING your time by fixing ignition, carbs, etc. but merely doing them perhaps out of sequence.

Now, if it's making bad noises, clanks or bangs, etc. then that's a different story...

But, of course, if the compression is shot on one side, the chances are that it ain't just sticky rings that are gonna loosen up. Pull the trigger on a rebuild, or take a chance - your call.

Post up some pictures of your new find, enjoy, good luck with it and again, welcome aboard!

Re: the rotating, of course, it shouldn't STICK, but since it WAS stuck, it might still have residual rust in that one spot. Also, the 360's have a crank where both pistons rise and fall together, so at top- and bottom-dead-center, there's going to be some resistance as both pistons change direction together. And there's always the changing resistance as the various valve springs compress and release as you rotate the crank.

Kirk
 

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Discussion Starter · #4 ·
Thanks for the quick replies.

I also am inclined to try running it as is and see what happens before resorting to a teardown.

[attachment=0:x70i19bn]IMG_0288.jpg[/attachment:x70i19bn]
 

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Welcome aboard Red. As you can see, help for all your troubles is just a click away! :p
 

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Looks nice!

Don't spend any more money or time than you can afford to lose, until you know what the TITLE situation is with this bike.

Wouldn't you hate to get it all cleaned up and running nice, then you go to license it and it turns out that the title belongs to someone from 20 years ago. I bet they would be grateful to you for fixing up their bike for them...
 

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Welcome to hondatwins and congrats on the free bike man!

One things for sure...those carbs are gonna need a good clean :?

kirkn said:
Also, the 360's have a crank where both pistons rise and fall together, so at top- and bottom-dead-center, there's going to be some resistance as both pistons change direction together.
Kirk, the 360's have a 180 degree crank.....one up, one down ;)
 

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the thing is when a bike sets that long it usually has a valve in the open posistion, resulting in loss of compression due to either valve being partly stuck open or rust build up on valve seat and or stuck rings, pump some penetanting oil into it and hopefully the valve wasn't stuck enough to be hit and bend by the piston
 

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Discussion Starter · #9 ·
Good call on the title-

The friend I got it from has had it since new so no worries about previous owners. He could not find the title but gave me a bill of sale. In my state (CT) bikes this old need no title to register. I will give a call to the state DMV before putting any $$ into it just to be safe....
 

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leethal said:
Welcome to hondatwins and congrats on the free bike man!

One things for sure...those carbs are gonna need a good clean :?

kirkn said:
Also, the 360's have a crank where both pistons rise and fall together, so at top- and bottom-dead-center, there's going to be some resistance as both pistons change direction together.
Kirk, the 360's have a 180 degree crank.....one up, one down ;)
Y'know, for years I've thought the 360's had a 360-degree crank. I didn't believe you and had to go look it up in the service manual. Sigh. Here I've been spoutin' it wrong all this time... :oops: :oops:
 

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kirkn said:
Also, the 360's have a crank where both pistons rise and fall together, so at top- and bottom-dead-center, there's going to be some resistance as both pistons change direction together. And there's always the changing resistance as the various valve springs compress and release as you rotate the crank.

Kirk

The CB/CJ/CL360 is a 180 degree crank from what little knowledge I have of it..


GB :mrgreen:
 

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Discussion Starter · #13 ·
So a dumb question...

Can I pull the valve cover and see the valve stems and maybe look for a stuck valve without pulling the head?
 

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First, I'd run a compression test....
Then, afterwards, that would be the quickest way to do it, but you won't be able to see the problem if the "bend' is very slight, or right at the valve button weld joint except by measuring the closed stem lengths...... I'd pull the head and run the acetone test....But that's just me.......
 

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Discussion Starter · #15 ·
Another question,,, I decided to just put in some gas and see what happens. On one of the carbs gas comes poring out the nipple like thing on the bottom of the float bowl.

Should their be a hose on these or are they some kind of bowl vent?
Do you think my one float might be stuck or a problem with the needle?

Another question- Since my kick starter shaft os broken I have to push start. I would like to check for spark but this is not easy when pushing to turn it over. Any suggestions??

Thanks
 

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clean/ rebuild the carbs....
Fix the kicker, it's not that hard, and will allow you to check/clean other engine areas....
 

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They are floatbowl overflows. Connect a couple of 12" hoses to them and route them to the road, if you dont they may just piss over your engine. Do what steve said...pull the carbs and clean them. I think your float valve is shot or maybe just incorrect float height. But go though them anyways for peace of mind. Good luck :cool:
 

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Definitely clean the carbs. i cleaned my 350 carbs when i first got her, there was some funky stuff in those bowls.

Id check for spark before you do anything else. IMO.
Pull a plug out one at a time, ground it to the engine, turn the ign on, and rotate the engine via the magneto like youve been doing. Look for a fat blue spark.


Any bike thats free, is awesome. best of luck man
sincerely
-Dan Walsh
from beautiful south jersey
 
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