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Help v8 trouble

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Give us some background.

Was the 90 originally a V8? I.e. have you fitted the coil and associated wiring from the 3.9? My thoughts are along the lines of; if your old v8 had points, you would not have the ignition amplifier wired to the coil.

Do you have a feed to the coil which is live with the ignition AND while cranking?

Have you changed the rotor arm since the engine was last run? You must hold down the centre shaft when you pull the arm off.

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When I go the 90 it had a 3.5 carbs in it removed that replaced with a 3.9 and box even got the full loom to go with the engine

When I crank have live feed to coil and live when not cranked

I took the brand new dizzy off the old engine as I only just fitted that before I changed over (electronic dizzy)

I followed the Haynes manual done all the tests that it says

I'm gonna get a new coil tomorrow just to eliminate that

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Ok well without teaching you to suck eggs. You have a live feed to the coil, and on the same connector, a wire to one side of the ignition amplifier. Then the negative to the ignition amp and the wire to the fuel injection ecu to tell it that it's sparking.

If you have all that and have no sparks at all there must be a component failure. Is the king lead ok?

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Place a voltmeter to both terminals of the coil with the ignition on in the engine run position, you should get 12v (slightly more).... No voltmeter... Get a 12v lamp... Any lamp (not headlight or spot though ;) )

Lamp would illuminate (when connected to a ground too)

(Best idea is solder some wires to the lamp of use crocodile clips)

Turn the engine over and on one side of the coil (try both..) The lamp should flicker (voltmeter bounce..)

That proves the amplifier is working

Next take the ht lead off the centre pin of the distributor (the one that comes from the coil..) And try to find something like a bolt you can stick in the end of it (or better a spark plug), get someone to turn over the engine... Do not touch the bolt or sparkplug! If you must hold the lead keep fingers away from end you do not want to become the earth path

You should get spark... If so your coil should be fine (should be a strong spark able to travel a fair distance... Say 10mm 3/8 1cm

Now get a pluglead and try the same thing with the coil ht lead reinserted into the distributor

All being well at this point I'd suggest it's distributor timing. Or have you got the cap on the right way in the notch

If not well its the rotor arm (highest possibility or cap.. Less so..(librel does of wd40 can sometimes help to get you home..)

Hope it helps, sorry don't know what tools or what you may or may not have tried or know...


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quick update

it runs sounds lovley :)

so I went back up unit with a list of checks and worked through them slowly checking everything out

blow me hold staring me in the face was the problem i hadn't earthed the coil so quickly bolted to bulkhead she fired up

im happy now finally see light in end of the tunnel

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