Thread: Starter motor fun

Apologies in advance for the long post, but thought it was necessary to paint a complete picture.

Had a weird issue with the starter in the County this week.

Been driving it regularly since I got it back on the road a couple of months ago and never had any issues with the starter. Drove it Sunday, then on Monday night I hopped in and just click-click from the solenoid.
Initially I suspected the battery had died, but good bright lights on the dash, 12.4v at the battery terminals, and down to float charging after 15 mins on the charger showed that wasn't the case.

Checked the leads on the battery and both were tight.

Next guess was a dodgy earth lead. I ran a good jumper lead directly from the -ve clamp on the battery to the transfer case. Made no difference - so theoretically no problem with the earth side of the battery.

Checked the +ve lead on the starter motor and it was still tight.

Next I ran a jumper lead directly from the battery and touched it on the solenoid terminal. Only the same click as I got when using the key (so not an issue with voltage drop through the starter relay)

At that point I thought .... Bugger. Must be the motor itself. Probably my soldering from when I replaced the brushes during the conversion - thought they were all good joints but probably the Isuzu's rattled one of them to death.

OK - off with the starter (and the turbo dump pipe to actually get the starter out). On the bench, brush cover off - all looks fine.
Removed the solenoid cover and checked in there - all good - solenoid plunger nice and free and contacts clean etc.
Reassemble and test run using jumper leads from the battery. Works fine.

Hmmmmm.

Refit the starter - retest and all works fine now (and exhaust is surprisingly quiet with the dump pipe still off )

I'm guessing that it was a dodgy connection at either the -ve terminal on the battery, or the +ve on the starter motor as they were the only electrical connections I disconnected to remove the starter.

My lesson learned from two evenings in the dark and cold is that when dealing with these high current connections - what seems tight enough isn't necessarily electrically good enough, and its worthwhile taking the time to remove/clean and refit them before going further with your troubleshooting.
It may save you a lot of time from false diagnosis.

On a positive note, it also reminded me that I need to replace the earth lead on the battery with something a bit more substantial. Its still got the original one from when it was born as a V8 - I reckon my daughter's '94 corolla has the same size
Not sure if the factory Isuzu cables are heavier gauge, but the V8 ones are definitely smaller than the ones on my 300tdi D1.
Something to consider for anyone with a non-factory Isuzu - it would definitely make it easier on the starter with heavier cable.

Steve

Originally Posted by c.h.i.e.f

Auh common problem with mine also usually the fast clicking on and of I find is due to flat battery but this is not the case with yours.... If I turn key and get one click and nothing happens it is due to a dirty contact somewhere or the stater has stoped on a point where there is no electrical circuit through usually caused by a slighty stuck brush...so the method I use (not a fix because you could be there for yonks finding one) is to turn key on and off repetedley until finally it frees itself up and off it goes

Yes - had that on other vehicles. IME usually a sign of badly worn brushes and that the starter is due for overhaul/replacement. If its worn brushes and you persist with it then in some cases the brush can come half out of the holder, cock and destroy the commutator. Makes the repair much more expensive.

Originally Posted by JDNSW

May not be the case in your vehicle, but my experience has been a faulty engine/chassis connection.
John

Thanks John - yes aware of that one.
Mine has a good strap (new during the Isuzu conversion ) from engine to chassis across the LH engine mount. Was one of the first things I checked when it wouldn't start. I'm going to add another one in the original position across the gearbox mount when I do the heavier earth lead to the battery Should have done it when I put the engine/box back in but just never happened.

Steve