Engine doesnt stop when ignition ‘off’

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937carrera
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Re: Engine doesnt stop when ignition ‘off’

Post by 937carrera »

That's the standard low pressure oil switch, F22 in current track 29.

On the assumption that your '86 van has a late engine with the DOPS oil pressure system there should be a "relay 43" which controls when the oil pressure warning light comes on in the dash.

Ignition on, engine off the red LED should be illuminated.

Is there a second switch on the rear ?
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

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itchyfeet
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Re: Engine doesnt stop when ignition ‘off’

Post by itchyfeet »

itchyfeet wrote:Seen this before.
there are two circuits to the engine
one is ignition live the other is thermoswitched.
mix them up and you get this


The answer was staring you in the face 10 days ago.

“The truth knocks on the door and you say, "Go away, I'm looking for the truth," and so it goes away. Puzzling.”

― Robert M. Pirsig, Zen and the Art of Motorcycle Maintenance: An Inquiry Into Values
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937carrera
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Re: Engine doesnt stop when ignition ‘off’

Post by 937carrera »

To be fair, there was more than one issue to solve, and the PO seems to have been very inventive in his deployment of electrical repairs. Your photos were an undoubted help in solving this.

Do you agree with my explanation of what was actually happening ?

To the OP, I see you said there is a second oil pressure switch, so you do have a DOPS van. Is there a wire onto the switch, or is there a brown wire with a spade on, going to earth somewhere near the dizzy ?
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

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itchyfeet
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Re: Engine doesnt stop when ignition ‘off’

Post by itchyfeet »

937carrera wrote: Do you agree with my explanation of what was actually happening ?

I'm sorry I'm not following the tread, 10 days ago I was on holiday when I made that comment and so I was not likely to get into solving the problem and it looked like you were doing just fine without me :lol:
1988 DG WBX LPG Tin Top
1989 DJ digijet WBX Holdsworth Villa 3 Pop Top
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937carrera
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Re: Engine doesnt stop when ignition ‘off’

Post by 937carrera »

Yeah, your holiday post explained the absence from board postings, this was my conclusion

937carrera wrote:Hmm, I have been head scratching a bit, let me have a go

I think one of the connectors on the wire from terminal 30 on the intake manifold relay was connected to the connector for N1 (choke) or N3 (by pass air valve)

Consequently, once ignition was made live, the relay engaged and the battery live from the alternator became connected to N1 or N3, each of which normally receives power from terminal 15 on the coil. The current flowed to the coil, providing voltage to the other connections on terminal 15 of the coil, which in turn connects to F35 thermoswitch and thus to the coil part of the solenoid part of the relay, keeping it permanently engaged even when ignition was off.

As suspected, itchy was pointing in the right direction all along (as no doubt did his pictures) , I'm delighted you got it sorted in the end.

Looks like another bodge on the oil pressure switches is about to rear its head. Based on what we've seen so far I'll be surprised if the wire to the rear switch isn't earthed....... and we know what'll be next :roll:
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

100leelee
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Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

Will check the wiring of the switches at the weekend....
Who knows what joys await..... :lol:

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