Hettie wont start on the button !!

[Nurse Julie]

 
Hi Chaps
Went to take the CB400/4 out today and for the first time ever, she would not start on the button. She has not been standing as have taken her out 3 times this week and she started fine with the kick start today. On the button it sounded like the solenoid was clicking, but then no noise at all from solenoid. Took her out for a ride hoping battery would charge but nothing. Definitely charging as lights go brighter when revving.
Battery charged to 15A on meter (off the bike), dropped to 13.7A after 3 hours. Have tried another new battery and tried 3 other solenoids, still nothing, had starter motor out which was turning freely on the button but then that stopped turning also. Tried keying the solenoid between the terminals and there were sparks. So, it appears battery has enough amps to start bike, unless 13.7A is not enough, power is getting from battery to solenoid and power is getting from solenoid to starter motor. What's happening and what do I try next ?
Ta in advance
Julie xx

[hairygit]

Think you're getting volts and amps mixed up young girly. Can trigger do a drop test on the battery for you ( that does NOT mean dropping it on the floor!) as it may have a cell that dies under starting load.

[stevush]

Maybe dodgy contacts on the button ? try a bit of contact cleaner in the switch.
I'd remove the starter and earth it somewhere then hit the button to ensure that its spinning OK when disengaged from the engine, if not then trace wiring back to the switch, if it is then it isn't engaging correctly

Steve

[Nurse Julie]

Think you're getting volts and amps mixed up young girly. Can trigger do a drop test on the battery for you ( that does NOT mean dropping it on the floor!) as it may have a cell that dies under starting load.

Yes,sorry, I always get them muddled up Hairy. Graham builds engines, he admits he hates electrics. How does he do a drop test?

[hairygit]

If he doesn't do electrics he almost certainly won't have a drop tester. Take the battery to any tyre/exhaust/car battery place and they will do it for you (hoping to sell you a new overpriced battery!) and if it checks out okay, you need to start checking the battery cables and connections (cables can break inside the insulation from years of vibration), still give enough power to sort low consumption items like ign system, indicators etc. But before any of that, with the engine not running, put your headlight on, and watch it carefully for one minute, if it dims noticeably, your battery is f##ked!

[Nurse Julie]

OK, I will try the headlamp. Also forgot to mention that with the original battery connected there wasn't even enough power to make the indicators flash. And no, Graham does not do electrics or at least the diagnostics in any shape or form. Unless it's cutting valves seats or honing bores or measuring bits in SOHC engines, forget it !!!

[Bryanj]

As a very quick down and dirty test using jump leads from a car battery(car NOT running) put the leads on the battery then the neg free end to a good bit of frame and touch the pos free end to the lead of the solenoid that goes to starter---if engine turns starter is OK so fault lies with solenoid or wiring to same, report back and i will give you more tests

[Nurse Julie]

Ok Bryan. I will report back tomorrow. I can't do anything until I find the jump leads, still in a packing box somewhere I expect !!

[Nurse Julie]

Hi Chaps.
Carried out the diagnostics as suggested by you all and it's all pointing to a knackered battery. With my extremely limited knowledge of Automotive electrics, I still can't get the gist of why a battery showing between 13.7 and 15 volts on the meter will not start the bike but she's as dead as a Dodo. All the terminals from battery through to starter motor got a good clean as well today, so something positive achieved from it.
Ta for advice xx

[hairygit]

Because you will see a battery is made up of 6 interconnected cells, and by the sound of it 2 have sulphated and died. They will give a good no load reading, but as soon as a load is applied they give up.

[Nurse Julie]

Love it Hairy, electrics in plain English, I understood all of that. Thank you

[K2-K6]

If you've got reasonable voltage reading on the battery and all the terminals are clean and tight then trying to start it gives a capacity \ load test the same as a dedicated test rig. Granted it doesn't give you a readout but slow or no start tells you its a fail anyway.

Another neat test they do on cars is to measure with a voltmeter from the alternator case to the battery earth terminal (yep I know they are both earth) but you should get a reading of less that 0.12volts (120mlvs) if it's higher than this then the earth leads and connects need looking at. Basically what you are reading is the inefficiency in your earth circuit as if the level is too high it's because the earth is tracking back through your meter rather than going where it should through the vehicle's earth system.

[AshimotoK0]

Sounds like slightly sulphated battery. When lead-acid battery becomes discharged, white lead sulphate can form on the plates, which is insoluble and causes internal resistance and this prevents the battery providing the high current demanded by the starter. Lead acid and Lithium ion battery don't like 'deep discharge'. That's why lithium ion power tools suddenly just stop ...because they are protected from 'deep discharge'

Did you try jump starting from a car battery?


Make yourself a nice cup of that tea you made me    and take five minutes to read section 6 of Mr Honda's manual in the link. It's got an excellent section on the technicalities of the electrics. (don't fall in love with the 'twins' though by reading the rest of the manual.

Here:-

https://www.dropbox.com/s/8i51vjqqdvllazj/CB350ShopManual.pdf?dl=0

[Nurse Julie]

Yes Ash, I will read it when I feel life ain't worth living any more and depression has got to the point of no return 
All sorts now anyway. Trig cleaned up all the terminals and fitted a new battery yesterday so starting perfectly now.

[AshimotoK0]

Yes Ash, I will read it when I feel life ain't worth living any more and depression has got to the point of no return 
All sorts now anyway. Trig cleaned up all the terminals and fitted a new battery yesterday so starting perfectly now.

Shame on you  Knowledge is king !