Thread: Starter motor issue?

I'm not sure if I have an issue with my starter motor (Lucas - Made in Australia) on 202 Holden motor. First the history:

I had a minor exhaust gasket leak so wanted to remove the extractors to replace the exhaust manifold gasket and the two gaskets at the joint between the two extractor sections and the exhaust collector. Carb removed, inlet manifold removed, extractors unbolted at the head. I moved to underneath and undid the bolts at the collector joints. When I had undone the rear extractor joint the extractor dropped down and shorted out the starter motor positive terminal. Dense smoke then appeared as the 6mm wire between the starter motor terminal and the alternator melted away. I managed to extract myself out from under the car and floundered around with a block of wood in the smoke until the wire was apparently off the metalwork. When the smoke cleared I then rigged the wood up to keep the "hot" wiring off the metal and disconnected the battery. (Wish I'd done that before!!!)

Although the starter motor was working fine before, I wanted to tidy it up while access was so free (just covered in oil and grime) so I removed it. I then rewired all the wiring that was damaged, which wasn't really much. The wire between the alternator and the starter terminal, the windscreen washer pump motor, the ignition wire to the starter solenoid and a couple of wires to the carby (runs dual fuel with LPG/Petrol). All the wiring is now nicely tidied away and wrapped in split flexy conduit zip tied around the perimeter of the engine bay and bulkhead.

I then removed the solenoid and took the starter motor apart. Cleaned everything and put it all back together. Tested the solenoid by connecting from battery negative terminal to the large solenoid terminal that has the earth connection to the chassis and also has the braided strap that disappears into the starter motor. Then touched the lead from the battery positive terminal to the ignition crimp terminal on the solenoid. The solenoid throws out and the drive gear slides along the shaft to the "engaged" end. All seems good.

I then put the starter motor back onto the engine and connected the wiring up and turned the key to start position. The solenoid makes it's nice click as it throws out but the motor itself doesn't turn. The power dead shorts (evidenced by the stereo resetting itself) and the fat cable from the battery to the starter motor gets a little warm!

Can someone suggest what's wrong or what test I could do to test it? I measure 0.4 ohms between the starter motor body shell and the large solenoid terminal with the braided connection to the starter motor. Also 0.4 ohms between the ignition spade connection on the solenoid and the starter motor body shell. That seems reasonable to me as there's supposed to be some coils between those terminals and earth inside the solenoid and starter motor isn't there?

The little gear at the end of the starter motor shaft is quite difficult to turn with my fingers pressing on the teeth while it's in the starter motor end cap housing, but it does rotate smoothly and not that different to when the end cap is removed and only one end of the shaft in a (plain metal) bearing. Seems okay to me, so why doesn't it turn with power applied? Help.

I'd rather not buy another starter motor if it's not the problem. Can someone confirm the wiring connections?

Cheers
John B

I've spent many years fixing Lucas starters of that type as they were fitted to all P76's. The simple faults include the inner terminal of the starter solenoid being tightened without checking the flexible link into the starter body. The rubber grommet in the body isn't very strong so twisting the cable causes it to distort and short out. The other common failure is the insulation of the field coils wears through with repeated movement. Open the starter up and inspect them for flaky binding. Sometimes they short on the through bolts on reassembly. Just remove the pole pieces and re-wrap the field coils with some cotton bias binding tape from a sewing kit. If you can't get the #3 Philips head screws out of the pole pieces just hit them with a medium hammer until they become loose enough to turn. I've had to do this repair on the side of the road, I had the car going again within an hour (with electrical tape instead of binding tape). Also make sure the starter body is exactly engaged in the correct slot in the alloy drive housing.

Finally remember to oil the bushes at each end and perhaps check them for excessive clearance. Worn bearings will cause the rotor to "pole out" on the stator and nearly seize. Then test the starter while its still on the ground or in a bench vice, stand on it to stop it jumping away. It should spin up freely and quickly.