Multi-spark spark plugs

[Hamish]

Hi folks,
Could do with some advice/guidance on this one :roll:
My VX has recently started 'mis-behaving' at low throttle settings. The carb has been taken apart (by me) several times and every component cleaned throughly. The first couple of times there was some crap in the system which I flushed out, and the fuel tank is getting replaced soon as it's rotten as hell :evil: But I do know it can't be blocked jets that's causing this roughness and occasional backfire 8O when it's cold. Now I've racked my brains for a solution (took all of 5 minutes :wink: ) and all I can come up with is changing the plugs as almost everything else is new.
I seem to remember reading somewhere that the 'multi-tip' plugs (I'm sure there's a correct term for such plugs but it eludes me at present :? ) are very good and give an improved spark, it's the only thing I can think that I can change easily.....
Any feedback appreciated :!:

I remember now :oops: 'Tips' :?: its electrode ah well, knew the old grey cells wouldn't let me down in the end :!:

[peter_coupe]

Hamish

I bought Bosch Super 4 few weeks ago, and I went back to standard Denso plug.

Bosch where really getting dirty, I had to clean them twice a week.
They just did not fire because of dirt accumulated on them, while Denso work even with all deposit.

Maybe Bosch don't like twin carbs, duno.

Peter

[chrisc]

Both of mine are living on new ngk v-groove single electrode plugs, and both have run fine using them - subtle ref to my no start post there! on the one i use daily no probs at all.

[andybeta]

there's a reference to plugs in Viva Lancia this month, don't think it's for Betas but talks about the number of electrodes/earthings in different brands and which provide better performance.

Andybeta

[andybeta]

For all those who delight in the VX engine, has anyone realised the similarites between it and modern turbo diesel engines - low revs and a lot of torque mean effortless driving. The Alfa 147 multijet turbo diesel engine delivers around 140bhp and 225lbs of torque and must be similar, if not more powerful, than the VX engine, certainly more economical!! Unfortunately it's not available in the UK. The Italians, head in the sand as usual...........Alfas web site is so prentious.......check it out.

Could Lancia follow the likes of Alfa, VW or Seat. All have pretty quick turbo diesels now and the engine similar in characteristics to a Lancia Volumex. Sacriledge.............

Andybeta

[Hamish]

Thanks for replies one and all :wink:
I'll 'get around to doing something' :oops: in the near future... currently it runs... so thats OK by me :!: The current 'bad behaviour' the car's exhibiting when cold and during 'stop start motoring' may be fuel related, rather than carb or spark as I still haven't fitted the new tank :roll: and the old one is a tad knackered....
What bugs me is that I can't attribute it's current behaviour to one thing (then I could sort it). I'm going to try one of my spare carbs and see if it works any better - it shouldn't as the one on the car is brand new, seriously clean and should be the dogs danglies :x
The joys of Lancia motoring :wink:

Interestingly enough - in response to Andybetas' diesel comments - I've just tried a Fiat 2.4JTD Marea Weekend (possible replacement for Mario) and was deeply impressed by the engines abilities although handling wasn't up to what I expected of a car 'three generations' beyond my old VW GL5 Passat estate. Perhaps I'll have to try something else :?:

[andybeta]

The Volumex characteristics are hard to beat when on song. The overall package of impecable handling, effortless long legged engine and sackfulls of style. It's indeed a labour of love.

Andybeta

[Hamish]

The Volumex characteristics are hard to beat when on song. Andybeta

That's what's bugging me :roll: the car is fine 'on song' or when well warmed up but when cold there can be a nasty backfire 8O and for the life of me I can't see why it should be doing this :!:
It's really beginning to annoy me intensely :x
I'm going to try new plugs and take the carb apart one more time to see if I can sort it.... I'm beginning to suspect the problem is more likely to be carb rather than spark related :( despite the fact the carb is new....
Runs like an absolute bomb at speed, just low revs it's misbehaving. The out and out bar steward :wink:

[andybeta]

Isn't there an enrichening device when the engine is cold or advance when the engine is at low revs? The VX induction system had so many devices to keep it runnung smoothly for all engine demands that these all need to be functioning. Sounds a bit technical. Might the mixture be the problem from what you describe ie carb?

Andybeta

[Will]

Hamish, did you check the thermal vacuum switch that activates the vacuum servo valve on the carb/intake manifold heater circuit?
I got my volumex in about 800 parts, and it took me three days to figure out how that little bastard worked- mine had been plugged where it was supposed to be a little intake filter and be able to draw atmospheric air to kill the vacuum signal to the vacuum servo.
Sneaky little bugger that setup is, and we know what happens with a cold intake manifold if the SC rotors aren't warmed up yet.
-Will

[Hamish]

I suspect Will is right.... I refuse to believe it's the carb, that swine has been on and off the car more times than a bad jockey running in the national :evil:
I'm off work on holiday in four days time :P so will have the dizzy off then... it simply cannot be anything else.
Right now I'm off to knock my head against a brick wall :roll: