74' CB360 Backfires but won't start

huck_finn

huck_finn

Been Around the Block
I posted over in electrical and worked through everything that might be cause my non-start from an electrics point of view.

I am kick start only
Rebuilt the carbs, new diaphragms on both and new seals on the bowls (jets were in good condition)
Float on carbs are set to 20 mm (I posted 19 on my other post, but it 20)
Fuel is in the bowls
Main jets are 100's
Get fouling on the plugs
Timing/Valve Height are correct
No air filters on the bike right now - will have stock filters pretty soon

The backfire that I get comes from both the left and the right, but never at the same time. One kick is comes from the right, the next few it might come from the left.

I just can't get the thing to start. Any help is appreciated.
 
interceptor said:
Does the 360 have the cam for the points that can be installed 180 degrees wrong like on the 350?
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Yup. Exactly what I was thinking. Other option is if the ignition coils were removed and put on the wrong side.
 
interceptor said:
Does the 360 have the cam for the points that can be installed 180 degrees wrong like on the 350?
Click to expand...

I don't follow - is it the cam that is installed improperly or the points?
 
huck_finn said:
I don't follow - is it the cam that is installed improperly or the points?
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It's the cam on the advancer, not the camshaft.

If you took the advancer apart or took the ignition coils off the bike, there could be issues with getting it 180° out.
 
Sonreir™ said:
Yup. Exactly what I was thinking. Other option is if the ignition coils were removed and put on the wrong side.
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It shouldn't be the coils - I haven't touched them, and it was running (albeit on one cylinder) before I began to tear it down. If it fires up when I switch the leads, what does that tell me? Is the advancer in there backwards somehow?

I did pull the advancer off when installing the new cam chain guide and tensionor - is it possible to install the advancer backwards?
 
huck_finn said:
I did pull the advancer off when installing the new cam chain guide and tensionor - is it possible to install the advancer backwards?
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Not usually. If you took the advancer apart, then yes. Otherwise probably not.

Have you verified timing by using a light?
 
Sonreir™ said:
Not usually. If you took the advancer apart, then yes. Otherwise probably not.

Have you verified timing by using a light?
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I used a test light to check timing - and the advancer wasn't taken apart. I will swap the leads over when I get home after work and see what happens.
 
huck_finn said:
It shouldn't be the coils - I haven't touched them, and it was running (albeit on one cylinder) before I began to tear it down. If it fires up when I switch the leads, what does that tell me? Is the advancer in there backwards somehow?

I did pull the advancer off when installing the new cam chain guide and tensionor - is it possible to install the advancer backwards?
Click to expand...
I don't think you can install the advancer 180 out, just the advancer cam. If I remember correctly on the 350, when you test the points with a light, the little tit on the end of the cam should be pointing straight up.
 
Figured it out - thanks for everyone that got me to take a look at my advancer, because I was going nuts. It just wasn't seated onto the post on the cam. As soon as I got it seated, set my timing again - it roared back to life...at least for a little while. Idled at full choke for about 45 seconds, then I had to adjust the choke to keep it going...then it died, and I haven't been able to get it to idle since.

I will post a new thread...or do some research before trying to solve this one.
 
Glad you found the issue :) No idle may be clogged jets? Some one on here said it only takes 5-7 days for jets to get clogged with this high ethanol fuel we have these days. Good luck.
 
Make sure there's enough gas in it. I just had this exact issue on my 750; turned out to be not engfyel in the tank. Sometimes it's the little, simple things
 
Cookie said:
Make sure there's enough gas in it. I just had this exact issue on my 750; turned out to be not engfyel in the tank. Sometimes it's the little, simple things
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It could be fuel - but I put some clear fuel lines on it - so I can see the fuel in the lines. And I will double check my timing, just in case there is something going on - not sure if there could be something that knocks it out of time - but everything is tightened down and buttoned up.
 
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