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Author Topic: It has a hard time starting, and when it finally starts it dies  (Read 3034 times)

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Offline leesfer

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #50 on: January 09, 2014, 07:12:32 PM »
Quote from: cheftuskey121 on January 09, 2014, 06:27:22 PM
you're using the "ultimate" coils with pamco right? I wouldnt think the coil could only fire one side...but put in new spark plug wire. if the problem persists, swap the NGK plug to see if the problem follows that plug. or you could do reverse order. in short, test each component for failure

Yeah, I am using the ultimate coils

It's 100% not the plugs, I'll change the wires and see.

If the wires were bad, wouldn't they not show the correct ohms though?
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Offline jonda500

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #51 on: January 09, 2014, 07:20:42 PM »
"I changed all the spark plugs and when I put it all back together I switched the #2 and #3 plug caps. I started it up and now #2 isn't firing instead of #3..."

In my mind this indicates clearly that the fault lies in the plug cap.
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Offline leesfer

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #52 on: January 09, 2014, 07:23:44 PM »
I would have to agree with you, if the coil can't be at fault and the plugs are not, it must be the wires
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Offline leesfer

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #53 on: January 10, 2014, 05:59:35 PM »
Holy crap she's alive!

Changed all the wires and now all the cylinders are firing and she is running.

Definitely is going to need to be carb synced now and adjustments but she is running which is awesome

Thanks to everyone that put up with this thread and all the help... I'm sure there will be more by me coming
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Offline seanbarney41

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #54 on: January 10, 2014, 06:03:46 PM »
good to hear, threads like these are always hard to provide useful help.  Everybody always wants to solve the most complicated problems...but it usually something simple.
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Offline leesfer

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #55 on: January 10, 2014, 06:10:07 PM »
That was a hard one to figure out because I had checked the wires for spark and the plugs as well and everything was sparking properly... I guess it just wasn't enough or intermittent for that one
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Offline cheftuskey121

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #56 on: January 10, 2014, 06:15:11 PM »
glad to hear it. going through the system piece by piece really pays off, even if it is a pain in the @$$ haha. enjoy :)
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Offline LesterPiglet

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #57 on: January 10, 2014, 06:46:24 PM »
It's easy to know after the fact but I changed my wires from the coils down 25+ years ago and have never had a problem with them. Those things just go brittle and can never function as intended.
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Offline mrbreeze

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #58 on: January 10, 2014, 08:05:19 PM »
Quote from: seanbarney41 on January 10, 2014, 06:03:46 PM
good to hear, threads like these are always hard to provide useful help.  Everybody always wants to solve the most complicated problems...but it usually something simple.
Very true! The last problem I had that was giving me fits was the power wire to my 2-3 coil. Not the side that connects at the coil.....the side that comes off of the wiring harness for the coil positve wire. It is one wire that branches off to 2 females.the males each go to a coil (stock bullets). The female to coil 2-3 was a bit loose which caused it to heat up and arc. Tightened and cleaned connection and it was good to go. It wasn't an obvious problem so it took a bit to find it. It is always said on here to check for clean and tight connections and that means you gotta be thorough!!!
« Last Edit: January 10, 2014, 08:07:05 PM by mrbreeze »
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Offline cheftuskey121

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #59 on: January 10, 2014, 08:23:52 PM »
Just don't make the mistake I did and solder the wires to your coils. you run the risk ondesolderin the other side of the tab inside the coil and ruining it. Ask me how I know. Nice $75 mistake.
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Offline leesfer

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #60 on: January 11, 2014, 04:26:02 PM »
Now that I've synced the carbs and have it running pretty well, I have one question... does this sound right?

The valve ticking seems really loud to me, but I have never heard another CB750 in my life to compare it to...

https://www.youtube.com/watch?v=6t77dlNr1-U
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Offline seanbarney41

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #61 on: January 11, 2014, 11:51:13 PM »
absolutely positive it is not an exhaust leak?....pop off all tappet covers and confirm you have tons of oil  to the cam, otherwise you got problems
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Offline leesfer

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #62 on: January 12, 2014, 03:21:47 AM »
Quote from: seanbarney41 on January 11, 2014, 11:51:13 PM
otherwise you got problems

Of course I do, that's my luck with this project

I'll check for leaks and oil tomorrow
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Offline pamcopete

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #63 on: January 12, 2014, 04:42:09 AM »
leesfer,

The clutch on the CB750 also makes a lot of racket. Try tying the clutch lever down with a tie wrap.
« Last Edit: January 12, 2014, 09:44:01 AM by pamcopete »
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Offline leesfer

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Re: It has a hard time starting, and when it finally starts it dies
« Reply #64 on: January 12, 2014, 03:46:18 PM »
It very well may be an exhaust leak. The sound is 100% coming from the head area around cylinder 3
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