« previous next »
Pages: [1]   Go Down

Author Topic: Starter/Solenoid/Battery Test  (Read 888 times)

0 Members and 1 Guest are viewing this topic.

Offline robdrobd

  • Who? Me?
  • Master
  • *****
  • Posts: 1,519
  • Isn't she a beauty?
Starter/Solenoid/Battery Test
« on: July 10, 2012, 01:31:51 PM »
1975 CB750k - Put a battery in this morning and tried to kick the bike over. It started right up after three kicks. Then I tried to use the start button and just got a loud buzzing from the solenoid. I wondered if something was wrong with the starter and the solenoid was not strong enough to turn it over. I turned the kill switch on and placed a screwdriver across the solenoid posts and the starter engaged and started the bike right up. Does this mean my battery was strong enough to kick the bike over, but not strong enough to turn the starter motor?
Logged

Offline Duanob

  • Bold Timer
  • Old Timer
  • ******
  • Posts: 4,011
  • Gotcha!
Re: Starter/Solenoid/Battery Test
« Reply #1 on: July 10, 2012, 03:27:19 PM »
Starter button is either dirty or malfunctioning. Common problem on these old electronics.
Logged
"Just because you flush a boatload of money down the toilet, doesn't make the toilet worth more",  My Stepfather the Unknown Poet

1974 CB360T
1976 CB550K2 Resurrected
1976 CB550F2 Barn Find
1979 CX500 VG "HONDA-GUZZI"
2007 Moto Guzzi Breva 750ie
2015 BMW F700GS
Another 1976 CB550K Cafe?

  __o
_- \_<,
(*) /' (*)

Online Kevin D

  • Old Timer
  • ******
  • Posts: 2,900
  • SE Michigan
Re: Starter/Solenoid/Battery Test
« Reply #2 on: July 10, 2012, 04:50:38 PM »
Why dont you take the solenoid apart, clean it, and try again?
Logged
71 CB750 K1
104,000 miles
Original Owner
———past———
70 SL100/125/150
70 Candy BlueGreen CB 750 K0
————————————————-
Former Honda parts kid/counter kid/do all
—————————————————————-
Whether you think you can or think you can’t, you’re right
Genius is 99% perspiration, 1% inspiration

Offline rickmancr750

  • Full Member
  • *
  • Posts: 24
  • If it's stuck, force it. If it breaks, it needed r
Re: Starter/Solenoid/Battery Test
« Reply #3 on: July 10, 2012, 05:00:30 PM »
+1 ^

Possibly the battery doesn't have enough charge. When the solenoid engages, the current goes way up and might have pulled so much current away from the solenoid coils it couldn't overcome the spring, and dropped the contact, which gives the battery enough grunt to pull the solenoid back in, which enageges the starter but there isn't enough current in the battery to run the starter and hold the solenoid in.
Round and round and round, dropping in and out. That'll make a buzzing sound.
Logged

bollingball

  • Guest
Re: Starter/Solenoid/Battery Test
« Reply #4 on: July 10, 2012, 05:07:27 PM »
Before taking the sol. apart clean all the connection. If it is clicking then the start button seems to be working. So either the connection are dirty or the sol. is bad.

Ken
Logged

Offline robdrobd

  • Who? Me?
  • Master
  • *****
  • Posts: 1,519
  • Isn't she a beauty?
Starter/Solenoid/Battery Test
« Reply #5 on: July 10, 2012, 05:22:01 PM »
Start button is brand new and working. When you say take apart and clean do you mean just clean the connectors or actually clean the internals somehow?
Logged

Offline TwoTired

  • Really Old Timer ...
  • *******
  • Posts: 21,802
Re: Starter/Solenoid/Battery Test
« Reply #6 on: July 10, 2012, 05:57:04 PM »
The solenoid has two small wires going to it which control activation.

Disconnect them and make jumper wires to reach the battery terminals.  The solenoid must activate cleanly each time a connection is made.  If it buzzes, it needs to be rebuilt or replaced.  If it operates reliably with the jumper wires, then you either have a switch issue or dodgy connection issues with the bike's wiring in the activation circuit.

Logged
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

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline robdrobd

  • Who? Me?
  • Master
  • *****
  • Posts: 1,519
  • Isn't she a beauty?
Starter/Solenoid/Battery Test
« Reply #7 on: July 10, 2012, 06:04:07 PM »
I can't find the rebuild FAQ. Can someone post it?
Logged

Offline Bob Wessner

  • "Carbs Suck!"
  • Really Old Timer ...
  • *******
  • Posts: 10,079
Re: Starter/Solenoid/Battery Test
« Reply #8 on: July 10, 2012, 06:18:35 PM »
Logged
We'll all be someone else's PO some day.

Offline robdrobd

  • Who? Me?
  • Master
  • *****
  • Posts: 1,519
  • Isn't she a beauty?
Starter/Solenoid/Battery Test
« Reply #9 on: July 10, 2012, 08:54:07 PM »
Thanks Bob! I will try that method first.
Logged
Pages: [1]   Go Up
« previous next »