7 replies to this topic

[mycoolmini04]

hi everyone,

i have a 1275 with a maniflow exhaust system (twin dtm backbox).
basically i have just changed the spark plugs which are the bp6es plugs, and since changing the old plugs for new
ones the car has been really spluttery but once i accelerate its fine just seems to be on tickover.
also the old plugs indicate the mixture is fine.

if i put the old plugs back in it seems fine again.i did think it was maybe a faulty plug so i tested them one by one with the old plugs so i
no its not that.

looking at the old plugs that were in the car look like they have a slightly bigger gap. but why would this be if theyre all BP6ES plugs?



another thing, i jacked my car up and noticed black oil coming from my drive shaft, i no its not engine oil due to it being black.
am i right in thinking the drive shaft has its own oil and has leaked from jacking the car up?




cheers
oli

[dklawson]

You didn't just take the new plugs out of the box and put them straight in your engine did you? With all the multitude of cars in the world it isn't possible for a plug manufacturer to make versions of each plug pre-gapped for each car model. You need to set the gap on new plugs prior to installation.

Check and set the gaps on all the new plugs and re-install them. If the problem persists, change one plug at a time (swapping in one (and only one) of the old plugs) until you've isolated which new plug is causing the problem.

[Sprocket]

Wasnt rh Designer an injection engine? Maybe not, im getting a picture in my head of a white mini with lovely lady in a tennis outfit, MMM. Nope, Edit, that was the advantage, isnt the designer also termed the Mary Quant? LOL and its not injection.

If it is injection, im afraid the plugs are the wrong ones, you need the BPR6ES. This has an internal resistor to surpress electrical interference. It can cause all sorts of problems with the injection system if not your neighbours TV, They wont be happy when theres snow on the screen during Coranation Street.

However im sure that the plugs should be the Resistor type even if its carb.

Plug gap should be set to 0.8mm

Edited by Mini Sprocket, 28 June 2007 - 08:15 PM.

[dklawson]

I believe from the first post (4th paragraph) you can assume all 8 plugs (new and old) are BP6ES. So, if it was running well on old plugs of one type, why isn't it happy with new plugs of the same type?

[mycoolmini04]

ok cheers,
no its not an injection its a carb.
i just opened the gaps up the same as the old ones roughly seen as i can't find my feeler gauges so used something else to estimate the gap.
i went for a drive and its alot better but the acceleration takes slightly longer to kick in, anyone know why this is?
maybe the gap is slightly to big now.


cheers
oli

[Sprocket]

I believe from the first post (4th paragraph) you can assume all 8 plugs (new and old) are BP6ES. So, if it was running well on old plugs of one type, why isn't it happy with new plugs of the same type?

Thats fair enough and i do realise that.

LOL, i can just see his neighbours wondering whats going on with the fuzz on the telly as well as all the house alarms going off as he drives down the street, lol, thats an extreme case example though. Ihave managed the later myself with the Ol' CB with the 100watt amp switched on, ahem but thats a differnt thing altogether

You really need to find your thickness guages and set them correctly. make sure the nipples are screwed on tight and the plug leads are pushed home correctly

[taffy1967]

My Mini has a carburettor, but because it has electronic ignition it requires BPR6ES Spark Plugs (if using the NGK type, which are great) like Mini Sprocket said.

[dklawson]

I can't comment about what is or isn't required when you have fuel injection.

However, on a car with carb(s), the rule of thumb is:
If you use resistor-type high-tension leads, you use "regular" spark plugs.
If you use solid core or low-resistance wires, you use resistor plugs.

In general you want the resistance from the dizzy cap end of the leads to the tip of the spark plug to stay below 10k Ohms. (10k is actually high... most run closer to 5k).