Turns over without turning ign key

PostPost by: gazzamuffin » Mon Apr 13, 2015 9:14 pm

Hi all,

I need some guidance

My ?lan has been working fine and I went to start it the other day tried and failed.
When I turn the ign off the engine continued to turn over slowly.

I ended up disconnecting the battery to stop it.

Every time I re connect it continues to turn over.

What can cause this?

Thanks
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PostPost by: 512BB » Mon Apr 13, 2015 10:06 pm

Wye I Gazza,

I had that exact problem 30 odd years ago. It turned out to be a fault in the control box, RB340. After replacing with a new one, all was sweatness and light.

Good luck with it.

Leslie
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PostPost by: john.p.clegg » Tue Apr 14, 2015 5:15 am

Sticking starter solenoid?

John :wink:
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PostPost by: Andy8421 » Tue Apr 14, 2015 6:24 am

john.p.clegg wrote:Sticking starter solenoid?

John :wink:


Could well be. As the contacts in the solenoid (really a high current relay) corrode and decay over time, the active contact area gets smaller. This leads to local heating, which can cause the contacts to weld and stay closed. If this is the problem, a sharp tap may release the contacts - however the problem is likely to re occur. I wouldn't bother trying to clean the contacts as the solenoids are 'sealed for life', a new one is the best way to go.
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PostPost by: 512BB » Tue Apr 14, 2015 7:29 am

When the control box in my car went awol, one of the contacts on a bobin stuck closed, or open, whatever. This allowed current to flow back from the battery, direct to the dynamo, which turned it into an electric motor, that kept trying to turn the engine over.

I shall be very surprised if this is not your problem Gazza.

Leslie

PS. When you say you disconnected the battery, I take it you mean you just opperated your battery isolator switch ????
PPS. Still marvel at the free kick goal you scored against the gooners in the FA Cup semi final, a few years ago.
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PostPost by: Andy8421 » Tue Apr 14, 2015 7:56 am

Leslie,

I have never seen that before.

I don't doubt your story, I have worked on old cars that had a dual purpose 'dynastarter', I am just surprised that a standard dynamo would be able to generate enough torque to turn the engine over.

Andy.
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PostPost by: Chancer » Tue Apr 14, 2015 8:21 am

Sounds a reasonable explanation to me, an inertia starter needs to accelerate very fast to engage, the only way that it can turn an engine slowly is to have turned it faster initially and then the battery discharging.

You would hear the starter engage in any case, dynamo sounds much more likely.

Editted, after carefully reading the first posting it could be that the solenoid contacts have stuck (not uncommon) and that the starter bendix is also stuck.
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PostPost by: 512BB » Tue Apr 14, 2015 9:56 am

Andy wrote: I have never seen that before

Well there you go Andy, you learn something every day, as I do, or try to !

However, I think you are reading something into my post that I did NOT say.

What happened, was that the dynamo TRIED to turn the engine over. I observed the dynamo pulley rotating, and in turn, was moving the fan belt, but the engine was not turning over, as even 25 years ago or so, when I was just a boy :lol: it was a well known fact that you kept the fan belt loose, to avoid the dreaded failed water pump. What was also noted, if my memory serves me, was the smell of burning !!!!!!! and much frantic frigging about in the boot, to undo a battery lead. So once again, I emplore ALL Lotus owners to FIT A BATTERY CUT OUT SWITCH in the boot.

So you were correct in one way Andy. I doubt too, the ability of the dynamo as an electric motor, to spin over a twin cam motor in good order. If it can, I suggest that the motor is nacked, with very low compressions.

It will be interesting to see what the outcome of this thread is. Get a move on Gazza, and stay off the bottle :lol:

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PostPost by: types26/36 » Tue May 12, 2015 10:48 am

Hi Gazza,
Just been reading your thread and was wondering if you had solved the problem, my guess would have been the solenoid but did you get a resolution?
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