Too much lead

Tom-D

Taxi to Parking
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Tom-D
I added some pictures of a cylinder with a stuck valve caused by too much lead..

http://www.whidbey.com/fairchild-nc19143/id7.htm

Any questions send me PM from here..

Feel free to re-use photos for examples why to lean the mixture..

also feel free to repost this at the red board.
 
Is it still snug in the guide? We had an O300D years ago that was too loose on one and would 'collect' carbon etc and stick... til replaced!
 
Is this engine a good candidate for an oil aditive such as MMO? I used some of that on my 145,000 mile Cherokee (Jeep not Piper) and ti solved a sticky valve problem. Perhaps ot could not be used in this engine to prevent a recurence?? :dunno:
 
NC19143 said:
I added some pictures of a cylinder with a stuck valve caused by too much lead..

http://www.whidbey.com/fairchild-nc19143/id7.htm

interesting pix.

is it truly lead (tetra ethyl lead) or carbon buildup? isn't lead usually grey looking? this appears black and sooty. this would lead me to suspect carbon buildup from blowby.

i'm no expert here, just wondering out loud for my own information. :dunno:

looking forward to your response!

blue skies,
 
This is why Franklin 150 engines don't like lead. We use auto fuel or carry TCP when we go 'out of town'.
 
trombair said:
interesting pix.

is it truly lead (tetra ethyl lead) or carbon buildup? isn't lead usually grey looking? this appears black and sooty. this would lead me to suspect carbon buildup from blowby.

i'm no expert here, just wondering out loud for my own information. :dunno:

looking forward to your response!

blue skies,

Usually "Blow By" is considered combustion pressure excaping past the rings and blowing by the piston into the crankcase.

Lead deposits are always mixed with carbon by-products caused by burning a hydrocarbon.
 
Thanks for the pics. Looks like you did a great job getting that engine looking like new again. Yes I agree that leaning is VERY important. I have gone over deakin's index many times and I feel he knows what he types.

I'm wondering with the J3 if a pilot in a cold part of the country should run the engine in the "red area"...lets say 75%+ power and 25 degrees rich of peak just to put as much heat as possible in the engine?
 
It takes me about 15-30 minutes to pull a cylinder and clean and polish the valve and guide, and put it back. remember this engine sticks right out where you can get at it.

This is a C-65-12 with 6 to 1 compression. it just won't make the heat required to activate the bromide lead scavenging additive.

We'll be doing auto gas this summer, and then this owner goes back to the Sand box for another year.

And then it gets pickled again. this time I'll do the pickleing and it won't have a stuck valve going back into service.
 
Iceman said:
I have gone over deakin's index many times and I feel he knows what he types.

Take Deakin with a grain of salt, he's not even an A&P, and he doesn't have any money invested in your aircraft.
 
NC19143 said:
Take Deakin with a grain of salt, he's not even an A&P, and he doesn't have any money invested in your aircraft.

Unless he happens to be a partner, no A&P has any money invested in your plane. Any GA pilot who doesn't read Deakin and use him as one (of many) source on which to make an informed opinion on engine operation is missing a great opportunity to learn.
 
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