Lancia Motor Club

Model Technical and Interest => Aprilia, Ardennes and Ardea => Topic started by: welleyes on 21 October, 2016, 08:19:14 AM

Title: Firing order again
Post by: welleyes on 21 October, 2016, 08:19:14 AM
It seems that the Tallack brothers are unusually obtuse; we are still confused by the plug numbering and the firing order. Briefly, we have a cap numbered 1-3-4-2. The books confirm that firing order. The books also refer to the front offside plug as number 1 and the front nearside as number 2. Ben's way of numbering is to take the front plug (front nearside) as No. 1 and the front offside as No. 2. 

3 and 4 have the same positions whichever 'system' one follows, but 1 and 2 are reversed. Which is correct? It seems to be implied that the car will run with the 'incorrect' positions but not as well as it should. To which plug should be No. 1 lead from the cap be attached?

Stuart and Andy

Title: Re: Firing order again
Post by: JohnMillham on 21 October, 2016, 09:28:26 AM
It should be obvious if the firing order is correct or wrong. An engine can't run properly if the firing order is wrong. The book is correct, as Lancia nearly always numbered the cylinders so that the firing order is 1234. The distributor rotor goes round clockwise, seen from the top - and the cylinders are numbered 1234 anti-clockwise, with the second cylinder from the front ( i.e. the front offside one) being number 1. Simples!
Regards, John

Title: Re: Firing order again
Post by: welleyes on 21 October, 2016, 02:16:59 PM
We don't surrender our family obtuseness that readily, John. Our plugs are connected to give a firing order of 1-2-3-4 using the Lancia plug numbering. Articles on maintaining the Lancia give the firing order as 1-3-4-2. The confusion, I can see now, is because the British articles on maintenance and service ignored the Italian plug numbering eccentricity and assumed that the mechanic would see the front plug as number one. Thus, the Italian firing order of 1-2-3-4 becomes the British one of 1-3-4-2 which is in such data as the Motor Trader Service Sheet. Unfortunately some of the servicing data over the years copies the British service sheets but uses the Italian illustrations showing the plug numbering. Just to confuse things, our cap is labelled 1-3-4-2.

Thanks, John.

Stuart (and pp Andy)

Title: Re: Firing order again
Post by: brian on 22 October, 2016, 04:12:44 PM
I totally sympathise as I had this problem early this year and ended up so confused that I asked a professional in and it took him over an hour to sort. I now have a laminated notice attached to a wire in the engine bay which details the order of cylinders from the front, the Lancia number thereof and the number on the distributor cap they connect to on my S1 Aprilia that would be working if the differential was replaced. I will attach to a reply tomorrow!!!

Title: Re: Firing order again
Post by: brian on 24 October, 2016, 06:43:33 PM
Herewith the laminated chart I keep in the engine bay jic!

PS Unsure why it is called Winter87(2)!!!!

Title: Re: Firing order again
Post by: GG on 25 October, 2016, 12:34:21 AM

Title: Re: Firing order again
Post by: chriswgawne on 25 October, 2016, 05:59:16 AM
Memo to self:
Must do something like that for Aurelias as there is potential for similar confusion.
Brilliant Brian.

Title: Re: Firing order again
Post by: davidwheeler on 25 October, 2016, 04:28:49 PM
In my early Aprilia days, before I made some plug connectors, my Aprilia used to run around on 2 cylinders or so and I would hardly notice in Town!  The engine was smooth enough but just a tad feeble.