Loss of Power, Stall After Bumps

[sparko]

I use Shell Rotella T6 synthetic 5W-40 diesel engine oil and add 2oz of Techron to the gas tank at every oil change. Is it possible these are creating high temperatures that are eroding the Iridium plugs?

No.
please send all your worn out iridium plugs to me. thank you.

[Vision]

Yes the plug needed to be replaced.

[Ruffus]

Would be interesting to see such a plug. If possible take a pic and post it please.
I'm using iridium plugs since years on several vehicles and didn't have such a problem.
Oily yes, but was caused by carb (too rich). Never had an eroded middle electrode. (pls see pics)
These plugs are from one of my GUZZIS taken out after ca. 20.000 kms.
As you can see the right one ran a little bit hotter, having this little specks of baken fuel on it..
Seen on the other pic, there was no eroding in this case.

[jeeves]

Yes the plug needed to be replaced.

Interesting.
Do you have a picture of one of them?
Iridium plug tips never deteriorate, the ground electrode wears out, but that takes a lot of km.

[Stig / Major Tom]

As for adding a fuel additive to the tank every fill up , maybe give some thought to using only a top tier fuel.
Fuels labeled at the pump as Top Tier have all the cleaning and protection additives necessary for any modern engine. TT fuels cost no more than other fuels.
Give a read to TT fuels....and who recommends them.

One less thing to worry about 🙂

Stig

[Iahawk]

Stig, you got me thinking about the top tier fuels so I did a local search...interesting that only the Conoco and Phillips 66 stations are on the list (and they are few and far between, but Cosco is on the list). Most of our available gas is at convenience store chains (Casey's, Kum & Go, Kwik Star).

Looks like top tier fuels must meet a minimum level of deposit control additives and must not contain organo metallic additives that can harm emissions equipment.

The retailer pays a fee to the marketing group to be able to display the Top Tier logo. What bothers me is that the non 'top tier' fuels may be just as good, containing the same level of additives but they haven't paid the marketing fee or had the testing done to get the approval?

Similar to some oil companies and approvals on engine oil..if you don't pay for the certification you don't get it...but you may be just as good...hmmmmm...

I do wonder about the fuel quality in much of the world where these scoots are sold in much larger numbers than in the tiny US market.

I guess with top tier you know they've passed the test..with the others you hope they have but don't know.

[Vision]

It's hard taking good pictures of the plug.

[Ruffus]

Interesting to see, seems like eaten off this electrodes upper tip. Saw this on standart plugs but until now, not on iridiums.

My hypothesis would be that, somebody tried to tap the clearance, demaged this tip and compustion did the rest.

Iridium has a melting point of above 2200°C, such temperatures are never reached in a motor.
Cannot think right now of something else as a cause.
Fuel and additives also might not cause that.

[Vision]

Thanks. I have no reason to think the plug was physically damaged since this life expectancy is normal for plugs in my scoot.

[Stig / Major Tom]

Stig, you got me thinking about the top tier fuels so I did a local search...interesting that only the Conoco and Phillips 66 stations are on the list (and they are few and far between, but Cosco is on the list). Most of our available gas is at convenience store chains (Casey's, Kum & Go, Kwik Star).

Looks like top tier fuels must meet a minimum level of deposit control additives and must not contain organo metallic additives that can harm emissions equipment.

The retailer pays a fee to the marketing group to be able to display the Top Tier logo. What bothers me is that the non 'top tier' fuels may be just as good, containing the same level of additives but they haven't paid the marketing fee or had the testing done to get the approval?

Similar to some oil companies and approvals on engine oil..if you don't pay for the certification you don't get it...but you may be just as good...hmmmmm...

I do wonder about the fuel quality in much of the world where these scoots are sold in much larger numbers than in the tiny US market.

I guess with top tier you know they've passed the test..with the others you hope they have but don't know.

Shell, Sunoco, Mobil around my town. Lots of them. Have yet to find a reason not to use TT fuels. Price is the same. Others not bothering to be certified is not my concern 🙂
I use the Shell Super 93 in everything but the cars.
Turns my mower into a hovercraft!
Stig

might have made up some of this....
Nasty looking plug!
Too much additives....or really lousy gas?

[Vision]

Nasty looking plug!
Too much additives....or really lousy gas?

I only use Shell 93 and the Techron a few times a year.

[Stig / Major Tom]

I only use Shell 93 and the Techron a few times a year.

With the Shell , you'll not need any additives.
Wrong heat-range spark plug?....because it sure seems like something strange is going on to do this routinely to your plugs.
Stig

[Vision]

Wrong heat-range spark plug?....because it sure seems like something strange is going on to do this routinely to your plugs.
Stig

I don't think so, it's the NGK (7544) CR7HIX Iridium IX Spark Plug.

[Vision]

Maybe it's the Shell Rotella T6 synthetic 5W-40 diesel engine oil.

[Ruffus]

One spark of suspicion came in my mind:
Little bit farfetched but...

-all sparkplugs with an "R" in its code have an built in resistor of 5 ohm, be it iridium or other
- if you have a sparkplug cap which has also a built in resistor of 5 ohm, resistance cumulates to 10 ohm and might show such a picture

Maybe we do have an electric engineer within here, who could go into this theory to say possible or nonsense?
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