Does that look like a plug that is running lean?

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neilbardsley
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Does that look like a plug that is running lean?

Post by neilbardsley »

Image

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Re: Does that look like a plug that is running lean?

Post by Nine One One »

Nope……………I would say it is looking good, could be slightly rich, but not lean.
If the base ring has a full turn of color with some spots of heavy dry soot, then jetting is too rich, REGARDLESS, if the porcelain is "BONE-WHITE", jetting is still……………...http://www.wallaceracing.com/plug-reading-lm.html

Don’t forget unleaded fuel does not leave the same deposits and your exhaust pipe no longer gets that nice brown colour any more
http://www.tuningmatters.com/how-tos/be ... r-setting/
Last edited by Nine One One on Sun Apr 03, 2016 8:13 pm, edited 1 time in total.
neilbardsley
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Re: Does that look like a plug that is running lean?

Post by neilbardsley »

Yes that is that I thought. There goes my theory that my car is running lean on the main circuit. I had convinced myself that the our denser air over here. Double the humidity in London v LA meant that our cars might need to move up a jet size?

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Re: Does that look like a plug that is running lean?

Post by 911hillclimber »

Never knew that about modern un leaded fuels not leaving a light brown deposit anymore!
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Re: Does that look like a plug that is running lean?

Post by neilbardsley »

Thank you. Now that I've read that site I'm actually thinking that I may be using a plug that is a little too cold but I think maybe I need to look at more plugs.
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Re: Does that look like a plug that is running lean?

Post by hot66 »

Neil ... You think too much :)

What's the problem with the running ? Why do you think your plugs are wrong?
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Re: Does that look like a plug that is running lean?

Post by KS »

The only accurate way to read a plug is to run (drive) the car at wide-open throttle then, with the throttle still open, kill the ignition and coast to a halt. THEN take out a plug and read it. Any amount of idling will give a false reading.
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neilbardsley
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Re: Does that look like a plug that is running lean?

Post by neilbardsley »

That is what I tried to do. Save for 2 seconds to get the car into neutral.
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Re: Does that look like a plug that is running lean?

Post by mycar »

hot66 wrote:
What's the problem with the running ? Why do you think your plugs are wrong?
I'm interested too. What's up with the engine Neil ?
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Re: Does that look like a plug that is running lean?

Post by neilbardsley »

Car is running very nicely but when pushed above 3500 rpm the temperature gauge moves higher a bit too quickly. I've almost ruled out everything else that I think it has to be the gauge

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Re: Does that look like a plug that is running lean?

Post by neilbardsley »

However I wondered if it was running a little lean

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Re: Does that look like a plug that is running lean?

Post by mycar »

So you're tootling along, minding you own business, engine all nicely warmed up, keeping it below 3500 revs...

Where's the needle on the temp guage now ?

Then, all of a sudden you notice the time and remember you're late for your appointment at the hairdressers, you put your foot down and the rev counter nudges 3500 revs ....4000 revs... 4100 revs !

Where's the temp needle now ?
neilbardsley
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Re: Does that look like a plug that is running lean?

Post by neilbardsley »

mycar wrote:So you're tootling along, minding you own business, engine all nicely warmed up, keeping it below 3500 revs...

Where's the needle on the temp guage now ?

Then, all of a sudden you notice the time and remember you're late for your appointment at the hairdressers, you put your foot down and the rev counter nudges 3500 revs ....4000 revs... 4100 revs !

Where's the temp needle now ?
First things first the rpm gauge is under running because at 80 it claims that I'm at 3100rpm so I have to adjust in my head! If I'm at about real 3.5k then I'm in the 180/190 range. Then if I push on I'm in the 210/220 range. The other bit to note is that the send is new I did a basic calibration of the two sender and I recommend this was was reading about 30F lower then my previous one. Which was perhaps reading high so previously, with the old sender, when I push on it moved towards 240. However, the engine never showed any signs of over heating.

I've exchanged emails with the original owner and he said it alway ran a little hot but he never had any trouble with it over heating even in some very hot conditions in Southern CA. He also added that on the last engine change the tach was changed from a mech to electric but never calibrated.
“A REMINDER. I would be grateful if those members who have borrowed bits from me in emergencies (e.g starter motor, oil cooler, etc) would return them and/or contact me”. – Chris Turner RIP
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Re: Does that look like a plug that is running lean?

Post by mycar »

Is all the tinware on this engine present and correct ?
neilbardsley
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Re: Does that look like a plug that is running lean?

Post by neilbardsley »

mycar wrote:Is all the tinware on this engine present and correct ?
Yes. I even have a panel between the oil pump and exhaust. Which many 356s are missing.

I should add that the moment I show down again the oil temp drops. This car is an industrial engine with the larger oil pump. I have good oil pressure throughout the range : 60psi.
“A REMINDER. I would be grateful if those members who have borrowed bits from me in emergencies (e.g starter motor, oil cooler, etc) would return them and/or contact me”. – Chris Turner RIP
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