engine on trolley no spark at plugs

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glee
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engine on trolley no spark at plugs

Post by glee »

Hello
I have a 1098 on a trolley after reconditioning it. It did start well and ran for a bit. Now I have a good spark at the points and not at the plugs. I have swapped dizzy and leads and rotor arm from van that works fine and still the same problem. Any suggestion would be appreciated.
Many Thanks
simmitc
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Re: engine on trolley no spark at plugs

Post by simmitc »

You should not have a good spark at the points :-?
I would normally agree with the old adage that it's never the coil, but if you have swapped the entire dizzy and leads for a known working unit then that really does leave only the coil. Before swapping anything else, remove the king lead from the dizzy cap and wedge the free end close to the block. Crank the engine. Is there a good spark there? If yes, then it has to be the rotor arm or the cap; if no then it is the coil or the king lead.
glee
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Re: engine on trolley no spark at plugs

Post by glee »

Thanks for the response.
It’s definitely not the coil as I tested that on the van and it started perfectly.
What do you mean by not having a good spark at the points?
Easy G
simmitc
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Re: engine on trolley no spark at plugs

Post by simmitc »

The points should open and close with only a minimal spark. Excessive sparking erodes the surfaces of the points. The condenser is fitted to reduce the sparking.

Have you tested with the king lead? Are the other HT leads fitted in the correct order?
oliver90owner
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Re: engine on trolley no spark at plugs

Post by oliver90owner »

What exactly do you mean by dizzy? I’m thinking you mean only the distributor cap, not the complete distributor.
JOWETTJAVELIN
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Re: engine on trolley no spark at plugs

Post by JOWETTJAVELIN »

As the engine is on a trolley, I would check the earth return to the battery. If you are using an ordinary jump lead with croc clip end, this may not be enough for HT current, especially if the engine is painted. So check the battery to engine connections especially for a good earth contact.
simmitc
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Re: engine on trolley no spark at plugs

Post by simmitc »

It's a good point about whether you really did swap the entire dizzy, but assuming that you did (as it's what you said you did) then did you set the timing correctly? That won't affect whether you get a spark, but could prevent the engine starting.
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