Starting Issues

[decoupe]

What I thought was a starter issue seems to be more a starting issue. I pulled the starter and had it checked with the result a new solenoid since there was moderate pitting on the contacts but the starter itself was good.

I have a suggestion for easier starter removal/installation - buy the cheapest 17mm socket you can and cut it down to the depth of the bolt head itself (1/4" or so). Finger tight the bolts to install the starter, slip on the socket and then slid in the ratchet extension and you should be able to torque it properly without any problems top or bottom.

Back to starting. Disconnected the trickle charger on a 1 year old battery. Put the starter back in and everything else that was removed. Engaged the battery disconnect switch and turned the key. Ran the fuel pump before ignition to fill the carbs. Everything fired up beautifully.

Turned it off and repeated - absolutely nothing! Zero noise or engage but the dash lights all normal.

Repeated and engaged and turned over very slowly but still started.

Repeated and started perfectly. Very random starting is the new normal.

Check all grounds and connections on both high and low voltage. It's not the starter, solenoid or battery.

Any other thoughts? Guess I don't need the after market broom handle - I'll put it on ebay.

Doug

 

[Malc]

Well it could be two things
Your battery isolation switch or your ignition switch. Both have to cope with a lot of amps when the starter is cranking and if the contacts are beginning to go they can cope with the voltage but not the high amps
Most modern cars have a heavy duty relay between the ignition switch and the starter solenoid to reduce this problem

Here's a trick that might find the problem for you.

1.. make up a good lead long enough to get from the positive battery terminal to the connection on the starter solenoid.
2.. Remove lead to solenoid from wiring harness attach your flying lead
3.. Out of gear, handbrake on
4.. Turn on ignition with the key but do not try and start.
5.. Jump you flying lead to the battery, starter should crank.

Repeat several times. If it starts each time it indicates (to me) that the electrical switch on the end of the ignition key barrel is beginning to fail.

Now, if possible, repeat again but this time use the flying lead to the "downstream" side of your isolation switch.
Note I am assuming this switch cuts off everything including the heavy power lead to the starter motor itself.
If it works every time then that would indicate the isolation switch is ok, if not then closer inspection maybe required.
Malc

 

[decoupe]

Thanks Malc. I'm pretty confident in the battery disconnect switch (new) but will give this a try both ways. First I'll check all the contacts and grounds.

Further refinement of symptoms - seems to be more of an issue when the engine is warmed up the when starting cold. That could be just coincidence.

Also seems to happen the further I get from the garage and tools.

 

[Honolulu]

battery

Older batteries develop what's referred to as "surface charge". They can deliver required starting amps only a very short time, before being so discharged they can barely crank (or not crank at all).

Thus, if your car is in good tune, one or two revs of the motor may be all that's needed to start, and you'd never know the battery is close to dead. Then one day you need three or four cranks, and it either doesn't start or quickly gives symptoms of a nearly dead battery - hence your very slow cranking.

Solution is to load test the battery. Many shops offer this service at no charge, hoping to sell you another. They put a heavy resistor across both terminals and observe the amperage (voltage?) - it should not decrease by a certain amount within so many seconds. I don't have a spec handy and of course it will vary with the stated capacity of each battery.

That said, I suspect you more likely have a bad connection somewhere. After a poor start, or no-start, feel the wires which carry heavy current. If you find one that is unusually hot, it's because high resistance = high heat, and you suspect that connection.

Example: I recently had an intermittent start problem with my K100RS (bike). After much flailing, I was surprised to find that the ground wire from the trans case to battery negative, did not conduct, though the terminal was clean. Turns out that just a little, but just enough, corrosion had built up between the wire strands and the criimped ring terminal, so that most often the starter would not crank. This was particularly frustrating since I had cleaned the ring connector, battery post, and attachment point already. But it wasn't enough! .... YMMV