buggritnarse.

Just spent about 2 hours of mixed daylight and darkness trying to see why Edward II is running like a bag of s**te, and failed.

current theory is that the distributor is shagged, causing the timing and/or the points gap to arse around enough to put the fire out. I don't think it's fuel, as 1) the carb was pretty clean, and in any case I cleaned it just in case; 2) the symptoms are intermittent (but enough to make it a pain) and 3) when the fire starts again it makes impressive bangs and sheets of flame from the exhaust, which leads me to think that it's the sparks that are missing.

Changing coil and condenser for other ones makes no difference to the fault symptoms. There is quite a lot of play and movement in the distributor, it has to be said, compared to what there should be.

Anyone got a decent series III distributor to sell?

Reply to
Austin Shackles
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Yebbut, you never follow the offers up so I've give up wasting my time. :-)

Martin.

Reply to
Oily

"Austin Shackles" wrote in message news: snipped-for-privacy@4ax.com...

I had lucoid dizzys with bags of play but rarely giving backfires only when chronically mistimed , have you tried putting a timing light on, if the play is really bad you see the timing mark dancing I suppose tracking in the dizzy capor coil nose is a possability, I wouldn't rule out a sticking needle valve either sudden surges of fuel always make for an interesting time Derek

Reply to
Derek

If it's a Lucas dizzy that can be caused by a break in the L.T wire to the points or the earth lead from the points plate to the dizzy body parting company as the vacuum advance moves the points plate around, otherwise condenser, you haven't got *two* bad ones have you?, that could happen.

Martin

Reply to
Oily

Faulty ignition switch?

Reply to
EMB

The intermittent nature of the fault does point to something other than the distributor (condenser excepted). The substitute coil and condenser might also be duff.

Also check the little pigtail lead from the contact breaker base plate to the distributor body.

I like the ignition switch suggestion - it's probably well worn and you're not dangling a large bunch of keys from it are you?

Reply to
Dougal

On or around Wed, 14 Mar 2007 23:24:23 +0000, Dougal enlightened us thusly:

Could be an iffy switch, I suppose - simple to check for, I can hotwire it temporarily. 'snot the original switch though, and seems in solid condition. The keys thing is not relevant as the fault manifests when stationary, and in any case, it hasn't got a heavy bunch on it.

There's a lot of play in the distributor - the top part of the shaft moves around in ways that it shouldn't. I'm wondering if the play causes random shifts in the points gap, and sometimes results in the points not opening.

It's not obviously moved, so the timing is more or less right. I've not put a light on it, mind - but when out the other weekend the fault came and went unpredictably, it'd run fine for a while, then go iffy, then after a bit run OK again.

Earth link from the CB plate to the dizzy body is one thing I didn't check - that could be loose and causing intermittent spark failure.

I'm inclined to put a new dizzy on it anyway - Beamends Richard has 'em for about 50 quid - since the old one looks well past it's sell-by date; if it doesn't cure the problem I'll have to look elsewhere.

Reply to
Austin Shackles

In news: snipped-for-privacy@4ax.com, Austin Shackles wibbled :

My money's on an iffy condensor. Bastards to check, and peanuts to replace.

Reply to
GbH

I wouldn't expect the consequences of this to be random/intermittent. It'd likely run (or not) like a pig all the time. From your description, though, it does sound to be on its way out.

Reply to
Dougal

'scuse me for piping up here, but I know sod all about carburetted engines and points etc, but am learning so just want to soak up a bit of info here. I thought the condenser (i.e. capacitor) was just for draining HT induction on the primary side of the coil, which is a prime cause of pipping on the points. Is there more to it than that, and can one going south cause more problems than sparks in the dizzy? Or am I getting my parts confused?

Reply to
Ian Rawlings

I'm not sure of the mechanism, and I really ought to be, but on the one occasion I had one go it took us forever to isolate it as the fault, symptoms were awfully similar to those described, very iffy firing if at all, then perfect for a while then only missing @ high revs, occassional sheets of flame. etc etc. Usual diagnostics, change everything, no improvement? change everything else.. good? WTF? Change everything back, now one bit at a time, fault replication only when whole dizzy swapped back, swap out bits of dizzy 1 AT a time, points OK, pigtail OK, rotor arm OK, cam OK, Bob weights, springs OK, Anything left? Condenser? they never go wrong! BTD swap, sweet as a nut!

Reply to
GbH

I was asked this the other day and had to look it up. See "Ignition Theory" about half way down the page.

formatting link

Reply to
kev

Nice page, thanks. I'll save that one off for reading with a mug of cocoa and my slippers.

Reply to
Ian Rawlings

On or around Thu, 15 Mar 2007 12:07:51 +0000, Ian Rawlings enlightened us thusly:

It does do that. I think it also suppresses the voltage spike when the points *close* and transfers the energy to the opening point.

as may be, iffy condensers can and do produce a startling range of faults and it might well be that which is wrong here, although it's giving the same problems with 2 different condensers, one of which was taken from a V8 points dizzy and was working IIRC on that.

I'm somewhat inclined to put a new dizzy on it, seeing as they don't cost much - if I go through and replace the points, condenser and rotor arm in this one, all of which look like they could do with it, it's still an old, shagged unit, and I'll spend no doubt about 10 quid in parts anyway.

Reply to
Austin Shackles

condensors are little buggers. If it goes it can leave you stranded. I spent hours sitting in my car on the side of the road after it would die unexpectedly and the condensor was the last bit of the whole system that i replced and the one that fixed it!

Reply to
Tom Woods

On the pinz I had some badly pitted points so suspected the condenser was shot, but from the sound of it, if it was, the truck wouldn't be running so sweetly. That's a relief as the bosch dizz on the truck apparently doesn't make the condenser easy to change, but I might have mis-heard.

Reply to
Ian Rawlings

On or around Thu, 15 Mar 2007 21:39:25 +0000, Tom Woods enlightened us thusly:

yeah, BTDT. it's not that common to get identical faults from 2, though. And something about this one says to me that it's a mechanical looseness somewhere causing erratic interruption of sparks.

new dizzy will eliminate a lot of guesswork in one go, and it was on the to-do list anyway for being old and shagged, just a bit further down the list hitherto. If it's still iffy afterwards, at least I'll know the dizzy is in decent nick.

Reply to
Austin Shackles

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