NC23 having other ideas on starting...

Forum rules
Please can you post items for sale or wanted in the correct For Sale section. Items / bikes for sale here will be removed without warning. Reasons for this are in the FAQ. Thanks
spritz46
Settled in member
Reactions:
Posts: 31
Joined: Wed Jul 13, 2016 9:16 pm
Bike owned: NC23, SRX long term project
Location: Derby, UK
NC23 having other ideas on starting...

Post by spritz46 » Thu Feb 01, 2018 9:37 pm

So the ‘quick project rebuild’ NC23 I bought I really starting to grind...

Points so far...

Basket case purchase,
K frame, J engine, J ECU and J carbs.

Got all back together, went for test start. Buzzing from solenoid. Fuel leak at carbs.
New seals and floats sorted for carbs but electrics/starting are causing stress.

Noticed the fuel pump wasn’t priming. Shorted it for test and pump works. Replaced pump relay, and again, and again. Works shorted out but not under ignition on with relay in. Starter solenoid makes rapid buzzing type sound still when starter button depressed. New heavy leads and full wiring loom of known good bike (including relays), same result.

Wiring currently goes heavy from battery to starter solenoid, other heavy from there to top post of starter motor.

Negative from front lower starter motor mount point to battery, heavy lead, negative from main loom originally on same mount point/ground point but have also tried earthed to frame with same result.

Starter motor removed and connected direct to battery, spins up but didn’t fully jump out my hand so to speak. Possible problem?

Also bike compression when tried to bump seems high, or certainly it skipped the back wheel rather than dragged engine round on dumping clutch during bump start test. Bump start test was also a fail.

Tried car battery and same buzzing from solenoid.

So, that’s about where I’m at. If anyone has a similar woe or indeed any advise as to which test route to take now to see where my gremlins lie, love to hear any advice. Summer is a looming and being half hour from Donnington means I’m itching to get her up and running before some improvement tweaks in time for summer.

Cheers for any help in advance

Matt

LITTLE=ONE
Site Supporter
Site Supporter
Reactions:
Posts: 119
Joined: Thu May 28, 2009 12:55 am
Bike owned: LOTS
Location: BEHIND THE BACK OF BEYOND
Re: NC23 having other ideas on starting...

Post by LITTLE=ONE » Fri Feb 02, 2018 9:37 am

Hello :grin:

Does the engine turn over ?

It sounds like the engine is sized , back wheel skips when you tried to bulb start it .

Remove the spark plugs , on the right hand engine cover there are two plugs , remove the larger plug and with a 14mm socket try and turn the engine over

Good luck

spritz46
Settled in member
Reactions:
Posts: 31
Joined: Wed Jul 13, 2016 9:16 pm
Bike owned: NC23, SRX long term project
Location: Derby, UK
Re: NC23 having other ideas on starting...

Post by spritz46 » Fri Feb 02, 2018 10:05 am

LITTLE=ONE wrote:Hello :grin:

Does the engine turn over ?

It sounds like the engine is sized , back wheel skips when you tried to bulb start it .

Remove the spark plugs , on the right hand engine cover there are two plugs , remove the larger plug and with a 14mm socket try and turn the engine over

Good luck
Cheers Little=one

No the engine doesn’t turn over on the starter so I was thinking after an unknown period being sat it was probably seized.

Was just hoping I’d missed something.

I can barely turn the engine over by hand if I pop it into second and turn the back wheel by hand so it seems it might be the case.

Anyone any tips for a poss seized engine? Part from the above which will be tried later today.

Cheers again for the reply little=one




Sent from my iPhone using Tapatalk

spritz46
Settled in member
Reactions:
Posts: 31
Joined: Wed Jul 13, 2016 9:16 pm
Bike owned: NC23, SRX long term project
Location: Derby, UK
Re: NC23 having other ideas on starting...

Post by spritz46 » Fri Feb 02, 2018 10:07 am

spritz46 wrote:
LITTLE=ONE wrote:Hello :grin:

Does the engine turn over ?

It sounds like the engine is sized , back wheel skips when you tried to bulb start it .

Remove the spark plugs , on the right hand engine cover there are two plugs , remove the larger plug and with a 14mm socket try and turn the engine over

Good luck
Cheers Little=one

No the engine doesn’t turn over on the starter so I was thinking after an unknown period being sat it was probably seized.

Was just hoping I’d missed something.

I can barely turn the engine over by hand if I pop it into second and turn the back wheel by hand so it seems it might be the case.

Anyone any tips for a poss seized engine? Part from the above which will be tried later today.

Cheers again for the reply little=one




Sent from my iPhone using Tapatalk

Sorry just to mention as well, turning the rear wheel by hand gives a lot of resistance but the plugs were still in on trying so I will update when I have tried plugs out.

Cheers


Sent from my iPhone using Tapatalk

spritz46
Settled in member
Reactions:
Posts: 31
Joined: Wed Jul 13, 2016 9:16 pm
Bike owned: NC23, SRX long term project
Location: Derby, UK
Re: NC23 having other ideas on starting...

Post by spritz46 » Mon Feb 05, 2018 10:13 am

LITTLE=ONE wrote:Hello :grin:

Does the engine turn over ?

It sounds like the engine is sized , back wheel skips when you tried to bulb start it .

Remove the spark plugs , on the right hand engine cover there are two plugs , remove the larger plug and with a 14mm socket try and turn the engine over

Good luck
Well plugs removed, look good apart from a little oil on cylinder number one plug...

Turned the engine over by hand with little resistance, went clockwise with the Crank bolt got just the sound of the engine turning through. Did a fair few revolutions and didn’t really get any easier so presume it’s all good. then tried counterclockwise and got dragging of a chain type sound from near the clutch area .

Is that the norm?

Don’t really know where to go to next with testing. Is it time for plugs back in and try bump/car battery start? I’m still a little puzzled as to why the fuel pump only primed on being shorted... could this be due to no tank being connected and so pressure is the same both sides of the pump?

Any further help will be greatly appreciated folks.

Cheers


Matt

pptom
NWAA Supporter
NWAA Supporter
Reactions:
Posts: 224
Joined: Sun Jul 05, 2009 5:32 pm
Bike owned: Nc23 x 2 and an nc30
Re: NC23 having other ideas on starting...

Post by pptom » Mon Feb 05, 2018 12:44 pm

If you don't have the tank connected the you don't really need the fuel pump, so you can take it out of the equation. I assume you're using a remote fuel tank?, as long as this is high enough fuel will feed under gravity into the carbs.
The fuel pump is only there because the carbs are higher than the Base of the tank.

spritz46
Settled in member
Reactions:
Posts: 31
Joined: Wed Jul 13, 2016 9:16 pm
Bike owned: NC23, SRX long term project
Location: Derby, UK
Re: NC23 having other ideas on starting...

Post by spritz46 » Mon Feb 05, 2018 1:11 pm

pptom wrote:If you don't have the tank connected the you don't really need the fuel pump, so you can take it out of the equation. I assume you're using a remote fuel tank?, as long as this is high enough fuel will feed under gravity into the carbs.
The fuel pump is only there because the carbs are higher than the Base of the tank.
Cheers pptom

It was more wonder as to why it wasn’t priming the pump when the ignition is switched on.

I get the gravity feed for testing idea, will this not reek havoc on the float needles? The nc23 has 2.4 floats not 2.0 which is what other bikes without the pump set up would run. Just don’t want to cause other problems in testing as I’m trying to work through all the gremlins.

Cheers for the advice, muchly appreciated.


Sent from my iPhone using Tapatalk

pptom
NWAA Supporter
NWAA Supporter
Reactions:
Posts: 224
Joined: Sun Jul 05, 2009 5:32 pm
Bike owned: Nc23 x 2 and an nc30
Re: NC23 having other ideas on starting...

Post by pptom » Mon Feb 05, 2018 7:20 pm

I've done it a few times on a couple of nc23's whilst in the building phase, had no issues whatsoever. The pump is very low pressure and fuel flow is still ultimately controlled by the floats which should always win.
Thinking about it, I do the gravity feed / pump bypass all the time, just done a couple of Dakar style bikes which have vacuum operated pumps, done all the running this way, including carb setup / tuning until the builds were finished and on the road. You've almost got to forget that it's pump fed, pretty sure that you could completely remove it as long as you don't let the fuel level get too far down in your tank. It's only to assist fuel flow, not to pressurise it.
Not sure on the priming issue sorry, to be honest I can't remember if it primes automatically or just when the starter is activated / engine is turning over.

pptom
NWAA Supporter
NWAA Supporter
Reactions:
Posts: 224
Joined: Sun Jul 05, 2009 5:32 pm
Bike owned: Nc23 x 2 and an nc30
Re: NC23 having other ideas on starting...

Post by pptom » Mon Feb 05, 2018 7:30 pm

Try leaving the starter motor connected to the engine and connect the good car battery straight across it to see if it turns the engine ok, plugs out of course, no need to have the ignition on, in fact leave it off to be safe. This should bypass all of the electrics and rule out the starter or any other mechanical issues. Personally I'd fire a bit of oil down the bores first as it's been so long since it was span up quickly.

spritz46
Settled in member
Reactions:
Posts: 31
Joined: Wed Jul 13, 2016 9:16 pm
Bike owned: NC23, SRX long term project
Location: Derby, UK
Re: NC23 having other ideas on starting...

Post by spritz46 » Mon Feb 05, 2018 9:18 pm

pptom wrote:Try leaving the starter motor connected to the engine and connect the good car battery straight across it to see if it turns the engine ok, plugs out of course, no need to have the ignition on, in fact leave it off to be safe. This should bypass all of the electrics and rule out the starter or any other mechanical issues. Personally I'd fire a bit of oil down the bores first as it's been so long since it was span up quickly.
Yeah good point that, cheers pptom. I’ll try get it firing on the starter direct and see where we go from there. Presuming all is well then I guess it’s plugs back in and full starter system trial again to see if it’s helped loosen things up. Just feels though with the engine spinning freely as it seems that the issue has yet to be found. Will report back when I get chance to do some work.

The fuel pump id like to keep in play just to keep that aspect standard however I do have a set of 2.0 needles and seats so if I get to the point of eliminating it fully then I guess I can always change over to them.

Cheers again for all the advice.




Sent from my iPhone using Tapatalk


Post Reply

Return to “CBR - General”