hmm not really sure what the problem is?.....

If it`s got wires, it`ll be in here.

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hmm not really sure what the problem is?.....

Postby ross.cheeks » 08 Oct 2007, 18:30

had the car set up on the rollers the other week and its been running fine, all of a sudden its being weird, it was driving alrite then it made a funny noise (kind of like a car bouncing off a limiter (duh-duh-duh-duh)) at low-mid rpm then it seems to clear and be ok but the same happens in next gear and so on, whilst its doing it there is just no go/pull in the car at all. im guessing that its something to do with the dizzy or something electrical but tbh i havent got a clue.

anyone know what it mite be?
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Postby Gordo » 09 Oct 2007, 07:34

Does it misfire or just lack power?
When it was "set up", what was done to the vehicle? I'd start looking in the areas touched then, such as if the dizzy wasn't tightened properly and has slipped or if a vacuum line has come adrift, etc.

Do you have a tachometer fitted? If so, an ignition problem is usually indicated by a flickering needle.
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Postby Shoveitpusher » 09 Oct 2007, 07:50

simple systems use simple answers.

check the basics, oil in the dash pot, diaphram intact, all pipes secure, dizzy cap secure and the stuff under it ok. plug leads secure etc. could also be something to do with the needle valve in the carb sticking (i know more about SU carbs than solex)

i would have hoped they suggested removing the vacuum advance and locking off the base plate so you only have weight controlled advance. the reason is in competition the vacuum advance can adjust at the wrong time and blow up the engine.
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Postby ross.cheeks » 13 Nov 2007, 12:13

went home this weekend and had a really good look at the car, 99% sure its nothing to do with the carb now.

checked all the leads and they were all ok except for the one that goesinto the coil, that seemed quite loose and had a bit of movemnt when it was sat in the coil, also checked the point's gap and they seemed a little close.

you cant really notice the problem as much unitl you try to drive it and its under a bit of load, then it just doesnt want to know, seems to be a bit of a miss and just no go in it what so ever.
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Postby Shellysowner » 13 Nov 2007, 18:38

I had this exact problem and it turned out to be a dodgy lead. Have you replaced the king lead?
Doive wrote:I remember last summer being in another Chevette with a quite mad driver, and we were drifting round A class roads at 65mph with the tail sliding progressively on the corners. It was fantastic.

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Postby ross.cheeks » 13 Nov 2007, 18:45

all the leads are new,

is that the one going from the coil to the dizzy, if so that one is the one that seems to be loose on the coil end.
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Postby Shellysowner » 13 Nov 2007, 19:34

Yes, that one.
Doive wrote:I remember last summer being in another Chevette with a quite mad driver, and we were drifting round A class roads at 65mph with the tail sliding progressively on the corners. It was fantastic.

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Postby ross.cheeks » 28 Dec 2007, 17:23

ive changed the king lead and that hasnt made any difference.

when the raid goes away will look at the point gap and the gap on the spark plugs etc
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Postby Doive » 28 Dec 2007, 20:29

Does this tend to happen with the engine warm/cold/hot/temperate? It sounds suspiciously like a spark breaking down. Is it only in the mid range rpm, can you drive through it and the car will start to pull cleanly again? Hmmm. It could be a vacuum advance advancing a bit too much and causing extreme pinking at mid rpms. Or it could be fuelling issues I guess?
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Postby ross.cheeks » 28 Dec 2007, 22:29

well its got worsenow that if was b4, theres just no "pull" in the car at all. n just reving it with out load you can hear it, put it under a bit of load by trying to drive it doesnt wanna pull at al.
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Postby Shoveitpusher » 29 Dec 2007, 19:35

i guess you would notice if it was pushing out a lot of white or blue smoke, but i'd do a compression test just to be sure. if you have a colour tune see if the mixture is ok across the rev range. (it's a simple and useful bit of kit for older cars also not outragously expensive, or at least it used to be)

check the diaphram again, it could be a pinhole getting worse. i'd change it just to be sure. i can't remember what the symptoms of condensor failure are but again i'd change that.

vacuum advances max out at very low rpm and don't do a huge amount, however disconect it and block the tube from the manifold.

it could be the advance weights have seized up. put a strobe lamp on the engine and check you do have advance without the vac advance connected.
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Postby Doive » 29 Dec 2007, 21:31

Can you isolate exactly where the noise is coming from? Front/rear/sides of the engine? If you can hear it when idling under no load then it's unlikely to be pinking. Condensors, in my experience at least, either work properly or fail completely, they tend not to be intermittent. If you can pinpoint more exactly where the noise is coming from I'm sure someone will have a fair stab at it.
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Postby Gordo » 30 Dec 2007, 10:19

Double check the points gap, replace the capacitor/condensor and check for loose/shorting terminals/connections and replace the coil.
Oh, check the filter - if fitted - on the fuel pump, give the fuel line a blow out and check the filter - if fitted - at the needle valve seat.
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Postby 1.8KADETT » 15 Jan 2008, 15:50

Try running the engine with the bonnet open in the dark. The darker the better. If you've a stray spark anywhere it'll be easy to see.

Could be a hairline crack in the dizzy cap earthing out?

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Postby ross.cheeks » 03 Mar 2008, 00:40

heres a video of it running, mite mate it a bit clearer what im trying to explain
Image

havent had chence to have a look at the car as its back home, have bought a single 40 and manifgold and going to get an electroinic ignition kit from aldon which should sort it out.
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