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V8 running rough - help !

Hi all - I've managed to break my V8 again.

Yesterday I fitted new spark plugs and it was going well (apart from an LPG switching problem but that's on another newsgroup) and today I fitted a new radiator. Upon restarting the engine it was obviously running rough and if you put a load on it by pulling away slowly it is quite obviously way down on power and missing - it feels as though two of the spark plug leads are crossed (which they aren't) but that's the best approximation that I can give to how it feels/sounds.

I've checked and rechecked plugs, timing, HT lead routing and that all connections to and from the coil are OK. The problem is also apparent when running on LPG so I've put it down to something electrical rather than fuel.

My reckoning is that I have disturbed something when fitting new rad - I did have the dizzy cap off to get access to clamp bolt for power steering pump and I was faffing around near the front of the coil. Like I said I have looked at all the leads/wires and they all seem fine - can anybody help with where to look next?

Graeme

Reply to
Graeme
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Is it on points? have they closed up? could be a faulty plug, put the old ones back in to try, they can be faulty out of the box. I can't think of anything other than the dizzy at the front of the engine you might have disturbed.

If non of the above try removing plug leads one at a time, to find if it's one cylinder, but i must admit this can be difficult to tell on a V8.

I started mine up one day and left a whole back of HT leads off, and my mate said "do you think it's running a little un-even?" and that was just on 4!

Let us know how you get on.

cheers

Gary

Graeme wrote:

Reply to
Gary Harrison

In message , Gary Harrison writes

A tip I got and modified - clip a timing light to each lead in turn and see if they're all firing regularly. The coil lead will give an overall problem, individual leads will flash (or not flash) erratically if you're not getting an HT feed or crossfire. I found it easier to slap the strobe light against my ear and listen to it firing rather than watching the flashing ... it makes your eyes go funny after a while!

Reply to
AndyG

SNIP>

Vacuum pipes to advance/retard on distributor?

Reply to
Rudolph Hucker

Thanks everybody - it was just me being a d*ckhead. I went back out this morning and tried all the tricks I could think of and the ones mentioned. Still lumpy. Pulled the leads off one at a time and the revs dropped each time - still lumpy.

Then I thought back to my original post 'sounds like two of the leads are swapped over' ??

Yup - pratt here had numbers 6 and 8 transposed on the dizzy, swapped them back and - yes! What a waste of 2-3 hours - must make a note not to fit black HT leads in future as they are hard to see in the dark

Reply to
Graeme

On or around Sat, 16 Aug 2003 20:30:31 +0100, "Graeme" enlightened us thusly:

ooops.

eaisly done on an 8 though - hell, I did it once on a 4...

Reply to
Austin Shackles

i allways had trouble with distributor caps on my v-8 . check inside the cap and clean all the eletrodes with a knife to scrape the oxidisation off them , so that the spark can jump the gap from the rotor arm to the leads .. check that the carbon rod in the centre is making good contact with the rotor arm .

if points ignition , the points can get pitted easily .

the condenser is one thing that may cause it to miss .

make sure the dwell angle is as per manual .

if using say SDI type electronic ignition , i did have one control box go on me , would run ok for first few mins and then start missfiring .

i suggest you check the dizzy cap forst and foremost , i allways kept an old cap that i knew worked ok , in case if times like this .

Reply to
M0bcg

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