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All Plugs Oil Fouled - looking for suggestions

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tapkaJohnD Avatar
tapkaJohnD John Davies
Lancaster, Lancashire, UK   GBR
So the Italian tune-up, and some new plugs, did the trick?

Meraviglioso! Avanti! Godetevi la vostra auto!


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Uberxy Avatar
Uberxy Steve Fox
Va, Charlottesville, USA   USA

Good luck with your TR. Often these cars suffer nothing more than previous owner neglect.

When I drove my current purchase home a few years ago, the car was very slow to accelerate. Yes, these are low horsepower cars, but my memory of owning one 40 years ago was of a much sportier car.

Got home and found 3 problems with the throttle linkage which prevented the throttles from opening more than halfway. All easily fixed, and suddenly I had the performance I remembered.

Have fun!

73 TR6
86 930

Edited 1 time(s). Last edit at 2019-02-08 06:50 AM by Uberxy.

tirebiter Jeff Garber
Dighton, MA, USA   USA
That much soot from only one step colder in the heat range ? It's seems a little unlikely but if the plugs keep coming out new and clean looking then that is what matters. At least they didn't soot up again immediately which is a good sign.

Apparently the carbs are not the only things that can cause incomplete combustion ... imagine that.

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poolboy Avatar
poolboy Ken D
Sandy Hook, MS, USA   USA
In reply to # 1594999 by POW Sounds encouraging Christian. Forget about it for a while and check the plugs in couple of hundred miles. Exercise is good. - Pete

Yes, I would not jump to conclusions and pop the champagne just because new spark plugs haven't run enough miles yet to develop color.....

ZS carb repairs

dsixnero Avatar
dsixnero Dan Colanero
Westville, NJ, USA   USA
Chris, the bp6es are the correct heat range for our cars. Those fouled plugs may have been caused by too many cold starts without a good run on the road. This often happens when trying to tune or solve problems with our cars. I have tried the 5's and 7's always come back to the 6's. New plugs always feel good, good fuel, good spark,good timing, get out on the road and run at a good temperature. Dan

poolboy Avatar
poolboy Ken D
Sandy Hook, MS, USA   USA
300 to 500 miles on NEW plugs, something like this:

ZS carb repairs

Edited 1 time(s). Last edit at 2019-02-09 09:13 AM by poolboy.

November 2017 001.JPG    38.1 KB
November 2017 001.JPG

barry s Avatar
barry s Silver Member Barry Stoll
Alexandria, VA, USA   USA
1972 MG MGB GT
1974 MG MGB
1976 Triumph TR6
1980 MG MGB
The BP5ES crosses with Champion 12NY. The BP6ES crosses with Champion N9Y. The hotter NGK plug compares most closely with the correct Champion for a TR6.

I need to now state (having just looked) the Driver's Handbook (repro in Bentley) confirms N12Y, however, parenthetically it also states N9Y for '73 thru '76. That being the case I'll stick with the hotter plug.

Edited 1 time(s). Last edit at 2019-02-09 09:27 AM by barry s.

poolboy Avatar
poolboy Ken D
Sandy Hook, MS, USA   USA
5's or 6's ....12's or 9's...a lot depends on how and where you drive.. as well as the engine state of tune and condition.
And about reading plugs....
I get feedback from folks who's carbs I've rebuilt and baseline adjusted..That's good, for even though I've determined baseline from what works on my engine and on the test engine when I had it, I like to get confirmation from others.
Sooty plugs with those rebuilt carbs invariably are from ignition timing errors...people who don't understand what's written in Haynes about "static" "ATDC", "BTDC" or whatever.. or those who do but still ignore or miss the point made in the actual text written in Haynes about "the recommended settings only 'nominal' ones".
I'll skip my Vacuum Gauge technique sermon this morning..

ZS carb repairs

Edited 1 time(s). Last edit at 2019-02-09 09:47 AM by poolboy.

POW Peter Wirth
HEBRON, NH - New Hampshire, USA   USA

Spark plug condition charts have always been intriguing to me. For the most part I was always pleased to not have any of the grossest examples in my engine. In the early '70's I was driving from Mass. to Colo., My '70 6 had about 91,000 hard miles on it and was going through 1qt. every 400 miles or so. Just one plug was constantly fouling while the others looked ok. On this trip at mostly interstate speeds that one plug built up a crusty hard carbon deposit that completely overwhelmed the plug tip and render the cylinder dead however, the hard mass was always the nicest shade of pre-leadfree gas grey. I ended up cleaning that one plug and adding oil at every gas stop. My point is plug readings obtained by highway running and top speed trials do not really tell the whole truth. That, along with stop and go and average speeds plug readings is more accurate, and to make maters worse, today's lead free and 10% ethanol gas makes for a cleaner looking plug over a wider range on either side of perfect. - Pete

poolboy Avatar
poolboy Ken D
Sandy Hook, MS, USA   USA
FWIW, this is what I send along with my rebuilt carbs.

ZS carb repairs

Rebuilt Carb Instuctions 001.JPG    44.4 KB
Rebuilt Carb Instuctions 001.JPG

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