Author Topic: Troubleshooting 1977 750F KEI HIN PD Carb Idle Circuit  (Read 5554 times)

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Offline Slayer

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Re: Troubleshooting 1977 750F KEI HIN PD Carb Idle Circuit
« Reply #25 on: July 24, 2009, 08:35:10 AM »
I just read the posts quickly. And didnt see the one thing I would look for. Float level. "Good suction but no fuel except from the accelerator pump" is what the man said. Just my .2 cents

I have adjusted the floats and when I open up the drains they all drain gas. Would you recommend measuring how much drains out on each carb?

Offline bikebitzofvt

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Re: Troubleshooting 1977 750F KEI HIN PD Carb Idle Circuit
« Reply #26 on: July 24, 2009, 09:34:31 AM »

It is possible to assemble the spark advancer 180 out of phase, getting symptoms above.


Not to hijack the thread, but how can one tell if the advancer and points cam are assembled correctly? 
Thanks!

On subject - how many turns out on the pilot screws from lightly seated?  Did you prove the pilot circuit with carb cleaner with those screws out?  They're on the bottom of the carb...
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Offline TwoTired

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Re: Troubleshooting 1977 750F KEI HIN PD Carb Idle Circuit
« Reply #27 on: July 24, 2009, 11:17:48 AM »

It is possible to assemble the spark advancer 180 out of phase, getting symptoms above.


Not to hijack the thread, but how can one tell if the advancer and points cam are assembled correctly? 
Thanks!
1 - the marks you put on each part of the assembly before disassembly, won't line up after reassembly.
2- you will get spark near BDC instead of TDC.  This is why I posted:
 
Remove the # one spark plug and crank the engine over to feel for compression at the spark plug hole.  In other words physically put the piston at TDC.
Then go look at the timing marks under the points plate.
Do the the 1-4 T marks align?
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

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Offline Slayer

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Re: Troubleshooting 1977 750F KEI HIN PD Carb Idle Circuit
« Reply #28 on: July 24, 2009, 02:08:20 PM »

It is possible to assemble the spark advancer 180 out of phase, getting symptoms above.


Not to hijack the thread, but how can one tell if the advancer and points cam are assembled correctly? 
Thanks!

On subject - how many turns out on the pilot screws from lightly seated?  Did you prove the pilot circuit with carb cleaner with those screws out?  They're on the bottom of the carb...

1.75 out. I removed the screw when cleaning and proving.

Last night I only had time to cover up some screw ups. A few days ago I turned the crankshaft with a pair of vice grips and I tore off the 2-3 points  :-[ Yesterday I installed and gapped the new points and I bought the correct size socket for the crank shaft. 23mm I think. I also switched the coil cables according to the true firing order. I was tempted to try starting it but I kinda want to adjust the tappets this weekend first and then give it a shot. I will keep you guys posted  ;D

Offline Slayer

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Re: Troubleshooting 1977 750F KEI HIN PD Carb Idle Circuit
« Reply #29 on: July 25, 2009, 05:13:09 PM »
I finished with the valve and tappet adjust. It was kinda fun not working on electrical or carbs. All intake gaps are .05mm and all exhaust gaps are .08mm. Cylinder #1 had good gap intake and exhaust. Cylinder # 2 intake was a little wide so I narrowed it a hair, exhaust was a little narrow so I opened it up a little. Cylinder #3 had good intake gap and exhaust gap was a bit narrow so I opened it up. Cylinder #4 had no intake gap at all and the exhaust was gaped to .05mm. I double checked that it was at TDC on the correct stroke and it was so I adjusted as necessary.

Next I performed a compression test.
Cylinder 1: 130psi
Cylinder 2: 135psi
Cylinder 3: 130psi
Cylinder 4: 135psi

I did another spark test and I am not getting spark on cylinders 1 and 4. I might have pinched a wire or something but I will get to this next. When it is sparking on time it is time to throw the carbs on and try again.   

Offline Slayer

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Re: Troubleshooting 1977 750F KEI HIN PD Carb Idle Circuit
« Reply #30 on: August 23, 2009, 06:01:39 PM »
I finally fixed the ignition problem and gave it more oil. I tried starting it up with the choke on and a few primed accelerator pumps with the throttle. It fired right up! This is the first time I got this bike to start and I have been working on it for about six months. She sounds like a singing angel haha! Thanks to everyone who has helped me out. I couldn't have done it without you guys  ;D Before I get too misty I did notice something alarming. The crank shaft was a little sloppy until I revved it up. I am thinking loose cam chain. It is not idling very well on its own but I stopped it to make sure I am not furthering any damage. In order to tighten it I have to be idling so should I just do it anyway with a bad idle?