Rover v8 misfire/tacho flicker

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V8dax2017
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Rover v8 misfire/tacho flicker

Post by V8dax2017 » Sun Apr 15, 2018 12:10 pm

Afternoon all, took my Dax rush out yesterday for the first time since engine removal and install, first half hour was perfect however after that I seemed to develop a misfire on all cylinders while at the same time it would loose power to the tacho, it did this a few times then would run perfectly for a couple of mins then back to this so I'm guessing it's a loose connection somewhere, it's running a carb so can't be a lot. Whatever it is it's where tacho and ignition are linked as both went at the same second. Any ideas where to look first or any tests that can be done to rule out various components.

Thanks Sam



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Re: Rover v8 misfire/tacho flicker

Post by DaveEFI » Sun Apr 15, 2018 2:31 pm

If you have the DLM dizzy with the amp on the side, the amp is the first suspect. When I had that dizzy, used to carry a spare amp.
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Re: Rover v8 misfire/tacho flicker

Post by JP. » Mon Apr 16, 2018 4:08 pm

Points dizzy?? check gap of the breaker points.
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Re: Rover v8 misfire/tacho flicker

Post by ChrisJC » Mon Apr 16, 2018 5:27 pm

Either the supply to Coil positive, or the link between Coil Positive and the amplifier, or the amplifier itself.

I would get a 12V bulb and a couple of long wires. I'd connect one side to Coil Positive and the other to earth and place the bulb inside the car.
The bulb should remain on all the time the engine is running. If it goes out or flickers, you've got a supply problem.
If it does remain on, and the wiring looks OK between Coil Negative and Amplifier, then change the amplifier.

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V8dax2017
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Re: Rover v8 misfire/tacho flicker

Post by V8dax2017 » Mon Apr 16, 2018 7:48 pm

Thanks for replies, it's running a msd blaster 2 coil and msd digital ignition so not sure if it has an amplifier? The distributor has the hall sensor type sensor in it. The bulb idea will still work though I'm guessing.

Thanks again

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Re: Rover v8 misfire/tacho flicker

Post by DaveEFI » Tue Apr 17, 2018 8:47 am

Dunno MSD. Is there fault finding guide for it?
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Re: Rover v8 misfire/tacho flicker

Post by JP. » Tue Apr 17, 2018 3:09 pm

Couldn't get my MSD6AL working properly on a Lucas Hall type distributor ending up with the early points type dizzy for a while. Finaly I bought the MSD Pro Billet dizzy which runs perfect for years now.
'73 Ford Capri. 3.5 RV8, Magnacharger 110 Supercharger, Merlin F85 Heads, Water/Methanol Injected
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Re: Rover v8 misfire/tacho flicker

Post by DaveEFI » Tue Apr 17, 2018 3:30 pm

Don't think any Lucas dizzy had a hall sensor. Tbe DLM has a VR sensor.
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Re: Rover v8 misfire/tacho flicker

Post by V8dax2017 » Sat Apr 21, 2018 6:43 am

All sorted turned out Msd coil was not playing game.
Thanks for inputs

Sam

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Re: Rover v8 misfire/tacho flicker

Post by scudderfish » Sat Apr 21, 2018 9:22 am

Back when my engine had a dizzy, I had numerous problems with coils and ignition amps. It was all caused by the regulator on the alternator being shot and putting out up to 17v. Give it a quick check.

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