chim 400 with new leads wont start

[kelvinwannell]

My Chimaera 400 serp, it was running with leads that melted, so a new set of leads installed (Magnacore 10mm), starts when cold and seems to tickover ok, with a good spark, once warm it will not start and appears to have a weak/intermittent spark and just floods. Any help appreciated.

Car has new coil. new alt, new MAF, cap and rota fairly new and worked before. Can cheap leads break down when warm???

[gamefreaks]

Did you change all of the parts at the same time? Theres been lots of reports here if new parts being a bit crap.

If so, i'd put the old parts (except the leads) back on and see if that resolves it.

Then swap in the new parts one at a time.

[kelvinwannell]

No, it was working ok, then replaced the melted leads, nothing else and problem started.

[Belle427]

Double check you have them all on the right order at the distributor.
Magnecor are not that bad in my experience but are not well regarded here.

[mk1fan]

Have you put them on in the right order?

Did you check all the alloy end caps of the sparkplugs where tight before fitting the new leads?

Did you put the distributor cap on the right way round?

I serviced my Golf Driver once and got the leads mixed up when putting them back on

[kelvinwannell]

dizy cap remained on, leads changed one at a time, so all are correct.

The problem seems to be when warmed up, the leads...or something is failing.

[Belle427]

Hard to see it being the leads, sadly it’s a process of elimination now.
Putting working old parts back on is the easiest way if you still had them, I’d start at the coil personally if it seems to run ok cold.
You could buy a set of cheap and cheerful Range Rover leads of you do suspect them.
Are the extenders still in place?

Edited by Belle427 on Tuesday 11th October 06:45

[KKson]

I had a brand new set of HT leads break down on me within days. Insulation failed where the king lead touched the rocker cover. Breakdown only occoured when engine warmed up. I ran the car at night, in the dark and the short was very obvious due to clearly visible sparks. The quality of new products these days is very poor. I've had ignition modules, dissy, coil and HT leads all fail in less than 7 weeks. My symptoms were exactly the same as yours.

Edited by KKson on Tuesday 11th October 07:09

[sixor8]

Are you still using the plug extenders? I had a misfire and discovered one of mine had failed (went open cct). It was an original, not one of the dodgy new stock.

If you are using them, IME cylinders one and two can have the leads go straight onto the plug without an overheating issue, but I've retained them on cylinders 3 - 8.

[kelvinwannell]

I do not use extenders, good set of heat socks are much better, been using them for five years. I will check in the dark tonight, that may be a good shout thankyou. Thanks for the help guys.

[Classic Chim]

Or maybe Ignition amp. Same as with coils they tend to fail when hot.
What caused your leads to melt.
If you are not using the metal extenders cheap socks protect the caps fairly well.

[mk1fan]

By chance is the longest old HT lead still useable?

If it is, try swapping out the new with the old one by one - check the alloy nipple on top of the spark plug is tight at the same time. Help to identify any poor leads.

I had a set of Magnacore on my Bora and the terminals weren't crimped onto the cables. Worth checking the connections between terminals / boots and the cables. Again a simple check.

Edited by mk1fan on Tuesday 11th October 11:00

[kelvinwannell]

I have a strobe extender, which flashes very bright and very uniform when cold, flashes intermittent and less bright when hot.

[GreenV8S]

The old leads may have been resistive. The Magnecore ones won't be. I wouldn't expect that to prevent it running but it might be revealing a weakness in one of the other HT components when hot. Does the problem go away when you cool the coil down? A bag of frozen peas wrapped around it is a good way to do that quickly.

[WOO5IE]

Ignition amp
Can typically fail when hot. It was my extenders that we’re failing.
Temp sensor on top of block helps control mixture.
Change thing one st a time as it gets very confusing.