Dodgy dissy cap.

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C.J.
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Dodgy dissy cap.

Post by C.J. »

Young Miss C.J.'s 'MoMo' broke down yesterday afternoon, causing mayhem on a very busy A41 into Chester.

I was 25 miles away so wasn't in a position to initially physically help her, but advised to try and re-start or 'bunny hop' it onto the pavement on the starter.

She rang back 10 mins. later to say she'd actually managed to get it going, and limped at 10mph into nearby Chester Zoo car park.

I rang the AA when I eventually got to her as it was indeed running very roughly, and in no way was going to be driven home.

Plugs and points checked, he turned his attention to the dissy cap, ignition leads and rotor arm, and suspected one of them.
Compression was fine which was my initial fear.

Only running on 2 cylinders, so dissy cap now the main suspect.....but.this was replaced only in January, and does indeed look new.
Magnifying glass didn't reveal any cracks however, so the mystery continued, and was duly towed home.

This morning, I found in a box of bits that came with the car, what looks like the original dissy cap, old and grubby, with matching equally grubby looking leads with original brass plug attachements! :o

Fired up, and perfect!! :o

Since been talking to a mechanic today that has a keen interest in old cars, and he tells me that plenty of dodgy poor quality spurious parts are now flooding the country, including distributor caps.

Anyone else had similar problems?
bmcecosse
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Re: Dodgy dissy cap.

Post by bmcecosse »

Yes - common problem - use good old parts where possible. Still - worth cleaning that cap thoroughly and trying it again - with the old rotor arm. Most ignition problems are reported to be rotor arm root cause.
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mike.perry
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Re: Dodgy dissy cap.

Post by mike.perry »

I have seen one side valve dizzy cap with all the Lucas markings which is a loose fit and wobbles around on the dizzy.
The identifying feature is that you have to remove the central carbon brush and spring to get to the coil HT lead clamp screw
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C.J.
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Re: Dodgy dissy cap.

Post by C.J. »

bmcecosse wrote:Yes - common problem - use good old parts where possible. Still - worth cleaning that cap thoroughly and trying it again - with the old rotor arm. Most ignition problems are reported to be rotor arm root cause.

The suspected dodgy one is still like new. Only done 500 miles with it, and was fitted by the previous owner in January.

Tried both the new and old rotor arms, but made no difference tbh.

Any other way of seeking out and finding a crack in the 'new dissy casing before I ceremoniously bin it?
I'm intrigued as to just how something so new can actually fail so seemingly completely.
bmcecosse
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Re: Dodgy dissy cap.

Post by bmcecosse »

That's the idea of the cleaning....so you can see if there is any surface tracking. Sure it's not just a loose HT lead ?
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C.J.
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Re: Dodgy dissy cap.

Post by C.J. »

bmcecosse wrote:That's the idea of the cleaning....so you can see if there is any surface tracking. Sure it's not just a loose HT lead ?

Nah. Checked all of them as did the AA man.
2 and 4 were out which virtually eliminated it being a dodgy or loose lead, I mean, why would 2 leads just randomly and suddenly become loose?

He suggested letting it run tough in the dark to allow the arcing to be visible.

Anyway, so glad I joined the AA now, as getting the car back home was going to prove to be quite tricky without them
Never thought I' was ever going to use them after all these years of paying
bmcecosse
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Re: Dodgy dissy cap.

Post by bmcecosse »

Does your Classic insurance not include Roadside and Recovery? All the 'good' ones do!
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C.J.
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Re: Dodgy dissy cap.

Post by C.J. »

bmcecosse wrote:Does your Classic insurance not include Roadside and Recovery? All the 'good' ones do!

Oh yes, but her (Miss C.J.) breakdown cover is for the car, not the person which would have meant her staying with the car.

She had a very important appointment to attend (the pub :roll: )for a leaving do, so muggins here had to sit with his 'personal cover for any car' in the Zoo car park for 2 hours in the freezing cold wind whilst she enjoyed herself. :evil:
bmcecosse
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Re: Dodgy dissy cap.

Post by bmcecosse »

If you had the spares in the boot - you could just have fixed it.....
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C.J.
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Re: Dodgy dissy cap.

Post by C.J. »

bmcecosse wrote:If you had the spares in the boot - you could just have fixed it.....
Indeed, but I didn't, so I couldn't.

Didn't even suspect the dissy cap at that point, with it being that realtively new and untampered with.
I thought the worst tbh. Dropped valve.
bmcecosse
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Re: Dodgy dissy cap.

Post by bmcecosse »

And if you put the cap back on now, the fault returns?
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dalebrignall
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Re: Dodgy dissy cap.

Post by dalebrignall »

i have been outside getting some red rotor arms to fit there were burs on the inside so they would not go on correctally .got them from a good sauce .just goes to show that you have to check the qualiaty of parts. i have my good old rotor arm on there ,and good old coil ,but i do carry a spare just in case .
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