4

I'm rebuilding a competition car based on a 1988 Lancia Delta HF and believe I have an issue with the starter motor. After fitting a fresh battery and ensuring that the kill-switch is on, 12.4 volts is measured between the +ve input pin of the solenoid and the ground strap bolted to the bellhousing / starter motor securing bolt.

Applying a +ve 12 volt feed to the exciter pin yields nothing at all. There is not even the usual "CLICK!" associated with solenoid operation. I've tried tapping the body of the unit with a hammer which has done nothing. For my next step I was thinking about pulling the starter from the car and bench testing it. However, I wondered if there was anything else I can try? I have considered using something fairly heady duty to bridge the posts on the solenoid. Is this a bad idea?

Also, if the fault lies with the solenoid, is it possible to strip it down and rebuild it or is it simply a case of replacement? The start motor is a Magnetti Marelli unit. The car is running a significantly stripped back non-standard wiring loom but the starter circuit is fairly straight forward.

Edit 1: Updated information

I've tried bridging the two terminals on the solenoid with a jump cable connected between the starter earthing point and the battery -ve terminal. This yielded nothing, not even a spark at the terminals.

I've also tried attaching a +ve jumper cable directly to the starter motors +ve input terminal and still nothing.

I suspect I have no alternative but to unbolt the start from the bell housing and strip it on the bench.

  • 2
    Following your original test, I would bridge the posts on the solenoid, just like you said. It will give quick indication as to whether the starter motor will run. – HandyHowie Jul 24 '18 at 11:40
  • I thought of doing this with a hefty flat blade screw driver. Hopefully something will happen. At the moment it's a steaming pile of disappointment. – Steve Matthews Jul 24 '18 at 11:52
  • 1
    You can test as @HandyHowie stated. If that works, you're golden. If that doesn't work, your next step is to bench test it. Take it off of the car, apply battery +ve to the main stud of the solenoid and ground (earth) the starter casing directly to the battery -ve. Then jump the main terminal on the solenoid to the starting terminal, which should give you an immediate reaction. If the starter doesn't jump, put the +ve lead directly on the starter motor power lead. This will tell you if it's the starter motor or the solenoid. – Pᴀᴜʟsᴛᴇʀ2 Jul 24 '18 at 17:00
  • Just replace the starter or Have it rebuilt. If you have power and ground and nothing's happening, then it's the starter. Solenoid, depending on starter, could be changed separately, but there's no real way of telling for sure it's not a stuck stator, and the starter probably has other issues anyway. – John Lord Jul 24 '18 at 17:59
  • 1
    Quick note: you can pretty easily weld your screwdriver between the posts if you're not careful, or if you leave it in contact with the starter for too long. (Ask how I know.) – 3Dave Jul 26 '18 at 14:11
2

I would suggest that you should make sure that the solenoid has a decent earth or ground - especially as you say there is no click.

Given that you say you are re-building this car, have you just painted all the inner surfaces of the engine bay? If so, then the solenoid may not be contacting metal for an earth.

You can test this by putting a cable between the case of the soleniod and the battery earth...

If the solenoid is integral with the starter motor, then the initial "pull-in" current gets to earth via the armature for what is called 'low power indexing" ie it causes the armature to rotate as it engages the teeth with the flywheel teeth. So, are the brushes making proper contact?

  • That's a good suggestion. I may run a jumper cable directly to the battery -ve terminal as the current earth strap, whilst the multi-meter indicates continuity, is routed terribly and may be pinched somewhere. I bought the car recently and was assured it did start so all I'm doing at the moment is trying to verify that. The disappointment in the workshop last night was palpable. – Steve Matthews Jul 24 '18 at 9:16
  • 2
    If there is 12v across the solenoid and starter motor bolt, then it surely cant be a earthing problem. If there was you would expect a voltage drop, or even 0v if the strap was not connected. – HandyHowie Jul 24 '18 at 10:03

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.