Dead starter motor?

[SimonP]

I posted to the thread: "starter won't crank at intermittent times" yesterday, but my problem is not, I think, the same, so I thought I'd start a new thread.

Original Post: A different (?) no crank problem
I have an intermittent 'no-crank' problem'. I can press the starter and engine will turn and fire. But if it doesn't go, I press the starter again -silence. But the Ammeter goes to full -30 (This suggests to me a major short.) Sometimes it will fix if I turn switches off an on again. Sometimes it starts after a rest. Any ideas?

Today's update - not good.
Had the same symptom, starter went first time, then not. But it has now stayed in the 'not' condition. Judicious rubber mallet hits on starter and solenoid, and powering down/up did not help. My boat has an engine power switch with off, blower, and blower/ignition, and a starter button. Both tested ok. Also continuity between starter button and solenoid contact ok. Pressing starter continues only to produce -30 amps on ammeter, and no cranking - absolute silence. Batteries are good. Evidence is pointing to a shorted starter, I think. Any diagnosis gratefully received. thanks

[Kelly]

SimonP,

Do you have a late or early model A4?

On the late model Delco starter and solenoid, you can bypass the solenoid for testing

by shorting directly between the big battery cable and the "S" terminal on the solenoid- Don Moyer.

This can be done with a screw driver held across the two posts. If the starter turns when you do this (every time) you can effectively remove it from your trouble shooting.

Also, with a late model setup, if you are getting silence when you press on your starter button this would mean that either the solenoid is defective (when activated you should hear a loud, solid click as the starter gear is engaged with the flywheel) or that the solenoid is not receiving 12V.

Hopefully this will help you narrow down your problem. Early model starters work differently so someone else will probably chime in on that issue. Also, I'm stumped with the ammeter activity.

Good luck,
Kelly

[Alain Croteau]

May not be your starter but the condition of your wiring. I had similar intermittent "no cranking" problems with similar ammeter symptoms. When this happened, the starter would sometimes crank if I positioned the battery switch to "both" batteries. If this didn't work, I would then short the starter solenoid with a screwdriver as suggested by Don M. When this problem became a more frequent occurrence, I installed a starter button inside the boat that was connected directly to the starter solenoid and this seemed to work. Once, however, while trying to start from the cockpit, I happened to touch the ignition switch wire and was surprised and concerned at how hot it became. I'm not an electrician but I suspected that as wires aged and corroded, resistance increases considerably inhibiting the flow of electricity. I rewired the engine using Moyer's kit and the problem went away. I retained the inside starter button but it is now used only in the Fall when turning over the engine to run antifreeze through the engine or to do compression checks.

[policecentral]

Old style Prestolite starter with external solenoid. Turn key, click, sometimes start, sometimes click, two or three tries to get engine started. Solution: new solenoid from MM. Starting is now solid, 100%.

Jim

[Kelly]

Jim,

I too had your problem with my late model starter w/ external solenoid: turn key and get "click"- sometimes three or four tries with clicks before getting the starter to run and turn over the engine.

Go here for one solution: http://www.moyermarine.com/forums/showthread.php?t=1913

Kelly

[SimonP]

Kelly and Jim
thanks for your input.

>Do you have a late or early model A4?

not sure, assume early. Serial number 286723, installed mid-late 60's. It has the thermostat dome, and does not have the oil fill tube over the flywheel housing, though its hard to tell, and my engine compartment is tight and the motor has the v-drive, ie mounted backwards. For this reason I also can't confirm if it has a casr or pressed flywheel cover. The carb is alu, but it is a recent replacement (not by me).

I'm attaching a pic, (lilofee atomic4.jpg) You can just see the back of the solenoid under the alternator bracket.

>On the late model Delco starter and solenoid, you can bypass the solenoid >for testing
I'm assuming I can't do this.

>Old style Prestolite starter with external solenoid. Turn key, click, >sometimes start, sometimes click, two or three tries to get engine started. >Solution: new solenoid from MM. Starting is now solid, 100%.

Jim, solenoid is external. On press starter: no click. And amps go -30.

[Kelly]

SimonP,

I'd like to see the front of your engine but from your photo it would seem to be a late model version (Delco distributor, domed thermostat on front of engine, late model oil dipstick...). I'm not sure about the oil fill tube over the reversing gear though. Could this be an add-on to accommodate the rear-facing set-up?

Here's another photo of my engine and the back of the solenoid. I've indicated the two posts to short in order to run the starter while bypassing the solenoid. Judging from your photo, you can do this, too. The top right post to short on your photo has the large battery cable attached to it.

Kelly

[Administrator]

Hi, Simon:

What's the metal cylinder in the lower left portion of your picture, with the turquoise-colored wires running to it and the letters "LASS" ( or something similar on the side)?

Bill

[SimonP]

Bill,
it is one of the many mysteries.... Its a safety device, I think, maybe a fume sensor.The 'lass' is 'Glass'.
The owner/builder of the boat was a german engineer, its incredibly well made with lots of (for the 60s) sophisticated stuff. Died 15 years before I found the boat. His family had helpfully dumped two sheds worth of spares and parts before I found it.


re :
Hi, Simon:

What's the metal cylinder in the lower left portion of your picture, with the turquoise-colored wires running to it and the letters "LASS" ( or something similar on the side)?

Bill

[SimonP]

Kelly
so would I

Electrics are odd. Today, I was all set to remove the starter motor. Wiring tests ok, but I am beginning to suspect an (electrical) fault in the oil pressure sensor, because one terminal wiggles and the other feels like it about shear off from fatigue. I cleaned the contacts and it started up fine. So I think the oil pressure sensor has to go.

[Kelly]

I love that copper exhaust pipe. Your German engineer worked pretty hard to get all that soldering to line up correctly!

Kelly

[SimonP]

Kelly,
its not copper, those are not solder joints, they are welds. Its pretty precise work.
Simon