Topic: CB750 still not running (pending).. what's the next step..

[ron.cieri.313]

Even after you replace the main fuse, as soon as you turn the switch it will blow again and you'll still be left wondering wtf.

Are you getting your display lights on (neutral and oil lights)?  Have you checked your battery with a volt meter?...I'm told all old Honda mechanics say "start with the battery"...and then work your way to the starter motor if the battery is good by bypass the solenoid with car batter cables, and see if the starter motor turns.

[oldhondarider]

Even after you replace the main fuse, as soon as you turn the switch it will blow again and you'll still be left wondering wtf.

Are you getting your display lights on (neutral and oil lights)?  Have you checked your battery with a volt meter?...I'm told all old Honda mechanics say "start with the battery"...and then work your way to the starter motor if the battery is good by bypass the solenoid with car batter cables, and see if the starter motor turns.

Are you getting your display lights on (neutral and oil lights)?   yes sir.
Have you checked your battery with a volt meter?.  no sir.. new battery.. have not checked it but I will
and then work your way to the starter motor if the battery is good by bypass the solenoid with car batter cables, and see if the starter motor  starter motor turns..  the engine just doesn't kick.

[oldhondarider]

wait... hold up... I'll go look at the manual first..    Don't want to get blasted for not checking first..lol

 

Should be one of the four in the box.

yup... all have solid filaments.

[ron.cieri.313]

and the starter motor turns over nice and strong...hmmm, doesn't seem like an air flow problem as if its not getting enough, it seems it would start and then choke itself off...so gas or spark.

Did you check your volt reading at the end of the spark plug?

...and if you're good there, have you ruled out plugged jets?...I don't think float level would prevent starting unless the were set so low it was preventing jets from dipping down into the pool of gas.

[oldhondarider]

Did you check your volt reading at the end of the spark plug?
 hmmmmmm good question... I haven't checked the volts at the spark plug.  do I just ground the black lead and then touch the red to the end of the exposed coil wire?  leave the setting on 20v and hit the starter?

and if you're good there, have you ruled out plugged jets
I thought I rulled out plugged jets... I pulled them all, cleaned, nice soak in carb cleaner and a compressed air shot for good measure, new gaskets.   but I could still have something buggered up.  ( didn't pull apart the carb assembly...just the bowl/jets/gaskets...

My guess on float level being off was that after about the 7th time on the starter ... I paused....and saw gas coming out of #4 and then eventually #1.

[TwoTired]

Many standard voltmeters will be damaged with too high a voltage.

Expect a voltage of about 20,000 at the spark plug, and that is a short duration pulse, not a DC level.
Make sure your test equipment can handle the voltage and type of electricity before you just probe about willy-nilly.

Since a good spark can be seen, you don't normally need to actually measure it to make is visible.

[ron.cieri.313]

Go with what Lloyd says...

It would seems it would seem fuel is the problem then...at some point, the fuel flow is not making all the way up into carbs.

What do you think Lloyd, make sure gas is making into the bowls and if so, would seem the carbs need a good cleaning?