Correct spark plugs for 1992/93 B200F?

[Stephen Edwin]

I'm prompted to check the correct spark plugs for my 1993 240 SE with the 2 litre B200F engine because instead of the part number specified by the owner's handbook both a Volvo dealer and Partsforvolvo, supply part number 272464, but the notes on the packet say they are suitable for the 200 up to 87 not mentioning the B200F. Those package notes do specify as suitable for the 300 from 85 onwards including with the B200F engine. On those plugs it is stamped 1367529.

It seems to me:

The owners manual specifies spark plugs for the 1992/93 240 B200F as: "Volvo part number 270747-9 (Bosch WR6DC or equivalent)".

But Volvo offer part number 272464 now and the Bosch WR7DC+ is specified in various charts and online.

Those updated part numbers might be an improvement but might be a compromise. Or re the Volvo part 272464 it might be incorrect given what is printed on the packet.

The Bosch WR6DC and + version is not recognised as existing by the Bosch plug selector site. But the WR6DC+ can be obtained still. The + can't be that significant? The WR6DC+ is probably closest to the original specification and I am inclined to buy those plugs.

I know that I worry too much about some stuff. I would appreciate any information, advice et cetera please.

Thanks.

[wooble]

NGK BPR6ES. In my experience the car likes NGK plugs better than the Bosch equivalent.

The number in the code is the temperature rating of the plug, i.e. the temperature the plug runs at. NGK and Bosch ranges don't align, however, with NGK plugs higher numbers = colder plugs, with Bosch higher numbers = hotter plugs. An NGK 6 is about halfway between a Bosch 6 and 7, maybe that's why the engine likes them better.

You can read the plugs to see if they're running hot, cold or just right (subject to the engine being in good health otherwise) - light grey-coloured deposits indicate optimum temp, heavy dark grey or black indicate too cold and a nearly depositless, glazed appearance indicates too hot. The plug that's optimum for your engine can also depend on the kind of driving you do - an engine used for long trips, high-speed driving or anything else that gets the engine good and hot would prefer a slightly colder plug to keep from overheating the plugs, and a car used for short trips or pootling about town would want a hotter plug to prevent fouling.

The + is just Bosch's designation for their latest version of plain copper plugs. I'm sure there's some marketing guff behind it, but it's still a plain copper-core plug you want. Don't fall for any upselling on multi-electrode, platinum, iridium plugs etc. They have their places, but it's just a waste of money in a redblock .

[Stephen Edwin]

Thanks yet again wooble.

And the proof of the pudding is ... the NGK BP6ES which were installed when the car was last serviced for me, are running light brown / grey. Kushtie.

I hadn't thought of just applying the old plug colour and condition test.

I guessed the multi electrode plugs et cetera must be "law of diminishing returns", useful in a highly tuned engine perhaps ...

I used to need N9Y






I'm curious about the WR6DC+ and the Volvo part numbers .... and we know what curiosity did! LOL

[wooble]

Eh, they have their places. Multi-electrode and rare metal plugs can deliver improved spark performance and/or longer plug life with an engine / ignition system designed to use them - the redblock is just a fairly agricultural design and won't make much use of them.

To be honest, Bosch plugs aren't BAD either - NGK are just my personal preference in my cars. Volvo plugs are just rebadged Bosch ones, if I remember correctly my owners manuals have specified both Bosch part numbers for different engine / year combinations. Denso are alright too, but I don't know the Denso part number off by heart.

[Stephen Edwin]

As a wrinkle, the Volvo dealer has found spark plugs part number 270746 which is marked on the packet as for the 200/700/900 from 1990 onwards with B200F engine ... that's my car. The packet is marked RESISTOR in gold letters.

I see NGK recommend resistor plugs if for example a car has any electronic engine management et cetera. I understand that the B200F does have electronic management. NGK advice re resistor spark plugs.
Apparently then the resistor plugs can avoid misfires and idling problems. I am becoming tempted to try the Volvo 270746 plugs.

[wooble]

NGK BPR6ES and Bosch WR6/7DC are both resistor plugs. The 'R in the part number designates them as such.

[Stephen Edwin]

Ah yes! Me was getting confuddled again. The plugs I have taken out are BP6ES .... so no R.

Anyway, as well as having your recommendation re BPR6ES, I think I've also got now the correct part number for Volvo plugs for future reference. 270746.

Thanks as always for all the advice.