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-   -   Lead in spark plugs! (https://vansairforce.net/community/showthread.php?t=43363)

Dayton Murdock 05-12-2009 10:13 AM

Lead in spark plugs!
 
Hi All
Last night I removed the lower plugs to find lead nodules in my plugs!
What is the cause of this and how do I change this condition?
Running P-Mags with NGK plugs
EGT?s around 1280F
CHT?s 300F ish

mahlon_r 05-12-2009 10:39 AM

You could try running the engine up to 1200 or 1500 rpm for a minute or so, right before shutdown. That should get the core temperature of the plug above the temp that the lead will harden and thus hopefully keep the plug cleaner and make the lead clunkers a thing of the past.
Good Luck,
Mahlon
"The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at your own risk."

tc1234c 05-12-2009 11:30 AM

Not to be alarmed
 
I do lean my engine and keep it lean until shut down. Yet I always find lead in my lower plugs. This is the tool I use to clean up plugs during oil change time:

http://www.aircraftspruce.com/catalo...theleadout.php

frankh 05-12-2009 11:39 AM

Dayton
 
Mogas is the way to go my friend..I know your carbed but have you tried cruising LOP?...As long as you have the correct instrumentation you might be able to do it..You'll save fuel and its kinder on your engine too.

Of course most carbs won't allow running LOP but some apparently will.

Frank

Mike S 05-12-2009 01:34 PM

Quote:

Originally Posted by tc1234c (Post 325547)
I do lean my engine and keep it lean until shot down.

I sure do hope you meant "shut down":eek:

DeltaRomeo 05-12-2009 02:06 PM

Normal
 
It's common, Dayton. No worries, Mon.

Find a buddy who is a dentist and get him to give you a couple of those pointy things they scrap your teeth with. During oil changes remove the lower plugs and clean.

I've been doing this as part of oil changes for 7 years now. Leaning while taxiing helps reduce it, but you will get them.

b,
dr

frankh 05-12-2009 04:02 PM

Hang on
 
Dayton your as cheap as me!...Gee for $5 for the bottom set of plugs just chuck 'em...:)

Frank

David Clifford 05-12-2009 04:44 PM

I have lead build up on the bottom plugs on my 0-235 L2C. I tried the high rpm shutdown method per Lyc, and just recently started adding the TCP fuel additive that is supposed to help. Well, after running through three tanks of fuel with the additive, I started to get hard starting and rough running. I pulled the plugs today and found the bottoms again built up with lead. Cleaned and rotated and she is running fine again. Doesn't look like the additive is doing anything.:confused:

tc1234c 05-12-2009 05:14 PM

Quote:

Originally Posted by Mike S (Post 325565)
I sure do hope you meant "shut down":eek:

Sure hope so:D

Dmadd 05-12-2009 08:39 PM

Auto gas with Marvel mystery oil mixed in will cure that. Put about half av gas half mo gas, but mix the marvel in the whole lot. (2 oz per five gallons.)
Engine will idle smoother too.

DM


Quote:

Originally Posted by David Clifford (Post 325599)
I have lead build up on the bottom plugs on my 0-235 L2C. I tried the high rpm shutdown method per Lyc, and just recently started adding the TCP fuel additive that is supposed to help. Well, after running through three tanks of fuel with the additive, I started to get hard starting and rough running. I pulled the plugs today and found the bottoms again built up with lead. Cleaned and rotated and she is running fine again. Doesn't look like the additive is doing anything.:confused:



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