Spring service and spark plugs

[HBG]

Hi folks.

I'm gathering the various bits required for a service and seem to have two spark plug options. Your thoughts please.

Currently in the car are BPR7ES which are a conventional looking plug. I have some more of these new.

I also have a new set of BUR6ET which have three curved conductors rather than the usual one.

The car runs fine with the plugs that are in now.

So what would you use? What do the 6 and 7 mean? Do you set the gap of new plugs or just put them in? How do you set the gap of the three pronged plugs?

Thanks.

[Scott]

A BP7ES is the standard recommendation for a 1.3.

B = 14mm thread
P = projecting insulator
7 = heat rating
E = 19mm thread reach
S = standard electrode

The extra R against your current use plugs means there's an inbuilt resistor (to suppress ignition inteference).

Your alternative BUR6ET plug doesn't seem right  Whilst a three pronged electrode is just to attempt to even a spark and prolong spark plug life (the T) ... it is the U and 6 that seem at odds with your current plugs.
I think the U indicates an inductive resistor type which would involve a different ignition setup and the 6 means the plug runs hotter than the 7 (which could cause preignition).

I'm not putting myself forward as an ignition specialist however and I'd be interested in other members' input. And given my Fulvia is due a Spring service too!

[lancialulu]

My advice stick to BP7ES. If plug fouling is occurring try going up to BP6ES. Some folk use the iridium equivalent but I have not seen any benefit and they are significantly more expensive. I have heard of Chinese copies of common ngk plugs circulating on ebay etc. so be careful of where purchasing.

[chriswgawne]

I have always used BP6ES plugs on our various Fulvias and Aurelias without any problems. That is not to say that this is correct - its just what I have used on many cars over the last 50 or so years.
If BP7ES  is better, how would this manifest itself I wonder?

[lancialulu]

NGK part finder says BP7ES for 1.3Fulvia. This is equivalent to champion N7Y.  BP6ES = Champion   BP6ES/N9Y are a hotter plug and risk preignition (and piston damage) at continuous high revs.

[Mark Webb]

I like multi electrode plugs, I did have some Lodge HL's many  years ago in my 1.3 coupe, purchased by a friend who ran a motor shop in Margate. The usual 2HL as used in Alfa Twin cams seemed a bit too cool and fouled up. He came back from Italy with his Fulvia loaded down with just about every option of Lodge available in the early 80's. Being a patriotic Italian he wanted to promote them, but everyone turned their nose up and bought Champion and NGK anyway! They are probably difficult to get now. I do run Bosch super 4  marked W56 on the (new spare) packet but WR78 on the metal body and r6 on the insulator( why confuse us? ) in the 1.3 Zagato. Have done for years with no issues. Multipoint plugs only actually arc at one electrode, but the outer seemed to shield the insulator from incoming oil from worn guide seals on an older engine and prevented fouling due to build up on the insulator. It just harmlessly built up on the outer electrode, not a great engineering solution but got over the problem at the time! They do seem to last forever though and seem less prone to fouling. The NGK iridium plugs in my 1.6 did seem a bit prone to detination and required a bit less ignition advance so, whilst I am happy with them they do seem a bit hotter than the D8EA's (maybe the fine tip is a 'hot spot'), so handle Iridium's with care!

[Edjsunfulvia]

I was sold these by Omnicron -see photo below . I have just found BP7ES at £2.65 on line. I paid £6.92 for each of Omnicrons. Fitted them two months ago but took out today.

I had them out today as my (new from Omnicron) leads were coming off. The reason the leads were coming off was because the plugs came without the little post on top, and I did not realise that these were required, dimwit. Fortunately a local classic dealer let me have some posts to screw on.

Question 1)
I thought these are shockingly dirty. Sympomatic of something?
Question 2)
Are these plugs supposed to be superior to BP97ES as def more expensive.
Question 3)
Can anyone confirm the firing order of the cylinders, just in case I put the leads back incorrectly. I obvs took great care to mark them before removing. Strangely car not running well since I put the posts on and cleaned the plugs. If you look at the photo of the Marelli distributor below, left to right, I think the order is 1-3-4-2.

Thoughts welcome, thanks chaps.

[Edjsunfulvia]

I was sold these by Omnicron:

just realised mine are the BUR6ET referenced by HBG above. Bet he knows to put the little caps on!

[HBG]

Thanks folks. I did spot the little caps were missing on the new ones so moved them over....easily missed though.

Interesting how dirty your plugs are Edjsunfulvia. I'm going to pop mine out this week and have a look. I think it's 6000 kilometres since I fitted them new and have noticed recently that the car is a bit lumpy at low revs though I have driven in town quite a lot recently which may be the culprit.

[lancialulu]

On a fulvia engine it is only fair to do a "plug chop" (remove plugs to see colour) after  a fast run with engine hot....

[HBG]

Just changed my plugs as part of a weeks long spring service....see pic.

[nistri]

It would be helpful to rebalance the carbs to ensure homogeneous plug light colour.

[Spider2]

Unless I am missing somethng but why are people changing their plugs annually? With modern petrol, especially Esso 99+ genuine brand plugs should last
20,000 miles. By all means pull them and give them a clean. If they are dirty then the new ones will get just as dirty.
Unless of course you are all doing 20,000 miles a year. Just make sure that genuine NGK BP7ES are fitted and not chinese copies.

[HBG]

Andrea, how often would you be checking carb balance? Mine were done about 6000 kilometers ago.

I agree regarding cleaning plugs. It's easy to fall into the modern way of replacement rather than refurb. I'll clean those that came out ready for next time.

The plugs on my bike are scheduled for replacement at 32k miles. Pretty sure they've not been out in the 31k miles it's done so far!

[nistri]

I check carb balance once a year unless they have been moved for other jobs. They are often misaligned especially after driving over road bumps, potholes etc. Even leaning on the air filter box is enough to upset the balance especially when the hidden support bar is missing or disconnected.

With modern fuel injection and rather lean mixtures, sparkplugs can last for a very long time. The story with multiple carbs is quite different and in the case of Fulvias many are overfuelled, thus needing plug replacement more often. Plus the potential harm from engine oil. It is also important to check the electrode gap (0.60 mm) that is not the one set at the factory.