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Gone in a Flash!
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If you were looking at a set of used Inconel valves, how can you identify that they are really Inconel and not some other cheap material? I'm looking at buying a used set of BBC aluminum heads from a guy that says that the valves have been upgraded. How much of a difference is there between Inconel and plain stainless?-This is for a 600HP N/A lake cruiser.
 

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If there are no ID numbers at all, you can run a strong magnet up the stem and the magnatizm will become increasingly greater. It is nice to have a standard high quality SS valve at the same time for reference.
 

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Interesting story......

The guy who did my motor is really sharp and actually has some of his people working inside Delphi Corp who are the fuel cell people for GM.

He also has a customer who has LARGE Caterpillar engines producing electricity from methane gas at land fills. Lot's of big azz engines and they make a profit of $75 per hr each. 50-75 engines running at a couple different land fills. The engines keep breaking the head of the valves off and my guy re-does the cylinders and heads (separate stand alone cyls) and the valves keep breaking. Cat swears they are inconel valves and is charging the inconel price for them.

My machinist bought a valve from Cat and had it edm'd (electrically machined so no foreign metal was left from usual tooling) and as he said it, the people who told him what the make up was.....out of 100% they can tell each percent. It wasn't inconel...........

Inconel valves were made by a high end valve company and problem solved.

Jim
 

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Interesting story......

The guy who did my motor is really sharp and actually has some of his people working inside Delphi Corp who are the fuel cell people for GM.

He also has a customer who has LARGE Caterpillar engines producing electricity from methane gas at land fills. Lot's of big azz engines and they make a profit of $75 per hr each. 50-75 engines running at a couple different land fills. The engines keep breaking the head of the valves off and my guy re-does the cylinders and heads (separate stand alone cyls) and the valves keep breaking. Cat swears they are inconel valves and is charging the inconel price for them.

My machinist bought a valve from Cat and had it edm'd (electrically machined so no foreign metal was left from usual tooling) and as he said it, the people who told him what the make up was.....out of 100% they can tell each percent. It wasn't inconel...........

Inconel valves where made by a high end valve company and problem solved.

Jim

Sounds like misrepresentation on Cat's side. I can only imagine the entire cost associated with all the damage caused by this?????



Darrell.
 

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Inconel should be non magnetic at room temp. Depending on the type of inconel it could become magnetic if say dropped in liquid nitrogen. This might help.

http://www.specialmetals.com/index.php
But a stainless valve is not necessarily a inconel valve???
Isn't inconel a step above Stainless?

And yes, a big time misrepresentation by Cat.
I was surprised that the land fill guy with his money didn't sue Cat.

I think (?) he said these were turbo V-16 engines and dropped valves around 1,000 hrs. They run 24 hrs a day, boosted and are not shut off. Not an easy life.

Side story.....
Friend of mine had a twin engine plane that was turbocharged.
We flew from upstate NY to the Fla keys.
He ran it at full boost and then dialed the mixture lean until the exhaust side of the turbos GLOWED red. As a mechanic, I looked at them through vents/flaps the whole way down to Fla and back up thinking...... those damn things are bright red on the outside and must be white hot on the inside...........How the fukk does metal survive like that????

Jim
 
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