Jump to content

Recommended Posts

Hi Folks,

in early June my 4A was having fun - running slow in 2nd and then putting the power down. It would cough and splutter but then pick up and run well at higher revs.

 

I changed the NKG BP6HS for new ones and normal life was restored.

 

Through this week I was having the same coughing fits, probably done about 3000 miles plus, so today I changed the plugs for new ones and all is working well again.

 

Is there a problem with these plugs - 2 months / 3000 miles isn't much life for a plug.

 

They were Ebay plugs

 

Todays new ones are from Moss.

 

Are there better plugs?

 

Roger

Link to post
Share on other sites

Are you sure it is the plugs, or could another part of the ignition be a little marginal and showing up first as the plugs naturally wear / degrade

with use?

 

Do you have one of the very high voltage coils that might not be doing the plugs any favours and leading to the early death of the plugs?

 

https://www.scc-racing.com/racing-blog/warning-non-genuine-spark-plugs

 

 

Alan

Edited by barkerwilliams
Link to post
Share on other sites

Hi Alan,

I used a very complicated substitution of distributors (standard 25D and NEW ebay) and the fault persisted.

I used a new dizzy cap - same fault.

Old/Ancient leads everything was bad

New leads - same as the originals + new plugs and the fault was gone.

 

OK - tomorrow I will fit the old leads + the new plugs and see what happens.

 

However in early June I simply swapped the plugs for new and all was good for two months.

 

Roger

Link to post
Share on other sites

Hi Roger,

 

Could it be a faulty plug cap/lead, disturbed during the plug change, working OK for a while?

 

Cheers

Graeme

Link to post
Share on other sites

I strongly suspect fake plugs Roger. If you google you can find tips to differentiate these from the pukka jobs. I adopted NGK when recommended by SAH so you can tell how long ago that was. I have used nothing else since and never had a faulty plug, either BP6HS or BP7HS work for me so maybe I need a BP6.5HS.

 

Tim

Link to post
Share on other sites

I bought a set of NGK plugs from Ebay:

 

https://www.ebay.co.uk/itm/s2-4x-NGK-SPARK-PLUGS-Part-Number-BP5HS-Stock-4111-New-Genuine-NGK-SPARKPLUGS/173251147134?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

 

Very cheap, have just checked the plugs themselves, & also the boxes, & everything checks out as genuine (according to the video in post No. 2 above)

 

Working OK so far.

 

Bob.

Link to post
Share on other sites

I bought a set of NGK plugs from Ebay:

 

https://www.ebay.co.uk/itm/s2-4x-NGK-SPARK-PLUGS-Part-Number-BP5HS-Stock-4111-New-Genuine-NGK-SPARKPLUGS/173251147134?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

 

Very cheap, have just checked the plugs themselves, & also the boxes, & everything checks out as genuine (according to the video in post No. 2 above)

 

Working OK so far.

 

Bob.

I get mine usually from Euro Car Parts via EBay & they all seem to check out OK, having checked on YouTube for the fakes.

Link to post
Share on other sites

Hi Roger, back in the day when I was running a Kawasaki 1200 drag bike I had sponsorship from NGK in the form of a box of about 200 plugs, at the time my bike was running twin 40 Webber's and although it ran correct from 50000-11000 rpm it had a tendency to foul plugs whist warming up. I found that the resistance of the new plugs varied by quite a bit and the ones which worked the best were those with the lowest resistance. I would be surprised if all 4 plugs were duff so what I would suggest us change plug number 1 check resistance of old and new. If it runs no better put old plug back and change plug number 2 and so on. It only takes one dodgy plug to make it run like a pig.

I've been using NGK in my 4A purchased from TR shop each year at the International and never had any problems with them.

Two good plugs removed at last service show a reading on my multimeter of 0.48 with the ohms set at 20M. I would think that if the reading was 0.3-0.5 then ok but much higher and could be a problem.

Link to post
Share on other sites

Hello again Roger

Very interesting information regarding fake NGK spark plugs above. I use NGK BP7HS in the 4A. It used to run on (diesel) after switching off the ignition. The cooler running BP7HS rather than BP6HS solved the problem. The engine in mine is standard but the BP7HS plugs seem to work better with supermarket fuel.

 

Also I wasn't the only one a couple of years ago to fill up at the Morrisons in Brecon at the Welsh weekend and have the car overheating, coughing and spluttering on the way home. Fresh petrol cured that one.

 

I have a set of Motorcraft AE22C that are supposed to be equivalent to BP7HS or Champion L82YC or L81YC but haven't fitted those as yet.

 

Keith

Link to post
Share on other sites

Roger I have always used this company for spark plugs and never had any problems either with NGK or NKG :D

 

www.gsparkplug.com/catalogsearch/result/?q=NA12

 

Paul

Link to post
Share on other sites

There are an awful lot of fake NGK`s around mostly Ebay purchases but FWIW if you get a new NGK (even a real one) wet by flooding or running rich it will fail, they dont like getting wet. Once they have been run for a while then they will stand wetting no problem, this has been a known problem for years. Try Nippon Denso as they are a good plug.

Stuart.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

Please familiarise yourself with our Terms and Conditions. By using this site, you agree to the following: Terms of Use.