Engine missfire

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vee12jag
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Engine missfire

Post by vee12jag »

Hey guys, I hope you can help. I have just finished a full restoration of a 56 series 2 with the original rebuilt 803. The carb, dissy, generator and all other auxiliaries have been rebuilt or replaced.
The engine runs like a top but misfires when hot, under load. I have replaced all the HT leads and caps, checked the timing and point gap and adjusted the fuel mixture. I have even changed a new condenser for and old one which seemed to improve the situation somewhat but not completely.
Any ideas guys?
Thanks
Mark
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bmcecosse
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Re: Engine missfire

Post by bmcecosse »

Probably in sufficient fuel flow - or maybe valve bounce ! :D
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liammonty
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Re: Engine missfire

Post by liammonty »

Check the coil. A likely culprit, particularly if you've also replaced the coil with a new one.
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bmcecosse
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Re: Engine missfire

Post by bmcecosse »

Coils either work - or they don't.....Since this is at high revs only, poor fuel flow is most likely.
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liammonty
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Re: Engine missfire

Post by liammonty »

bmcecosse wrote:Coils either work - or they don't.....Since this is at high revs only, poor fuel flow is most likely.
PLEASE Roy, let's not get into this again. I'm tired of going over it! Sometimes, coils will begin to fail when they get hot, and then work seemingly normally when they cool down. I have had this happen with 2 coils, and I have seen several other people tell you tales of the same happening. In all cases, the symptoms were cured by replacement of the coil alone. We are trying to help vee12jag get his car up and running again, so I think it's only fair to consider all possibilities. And even if it's unlikely, the coil is indeed one of those possibilities. I don't think it mentions high revs, just being hot and when under load.
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oliver90owner
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Re: Engine missfire

Post by oliver90owner »

As a few other possibiities/questions.

Change the plugs? Is it one pot or all? Possible manifold leak? Sticking valve?
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vee12jag
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Re: Engine missfire

Post by vee12jag »

Thanks for the suggestions. I have indeed installed a new coil (screw in terminal type) from ESM. May try another. Don't believe it is a fuel problem.
Here's hoping I make it to Catton Park tomorrow. Look me up please if you're there. My car is a black 2 door. KBW 653.
Thanks
Mark
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liammonty
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Re: Engine missfire

Post by liammonty »

Good luck, and enjoy it!
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