Author Topic: Pros and cons of sodium filled valves  (Read 2610 times)

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gregaba

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Pros and cons of sodium filled valves
« on: January 19, 2022, 01:48:01 PM »
I finished lapping in my valves and was moving my head when a valve dropped hit the floor and broke.
I then found out it is one of the sodium filled ones.
I have allready replaced 4 of them with Ferrea valves and was wondering if I should keep the other ones I have or replace them.
Thanks
Greg

gt350hr

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Re: Pros and cons of sodium filled valves
« Reply #1 on: January 19, 2022, 02:04:31 PM »
   Do NOT run the OEM sodium filled exhaust valves for the exact reason you just experienced. They break!

gregaba

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Re: Pros and cons of sodium filled valves
« Reply #2 on: January 19, 2022, 02:07:49 PM »
Thanks
That is what I was thinking.
Greg

TomP

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Re: Pros and cons of sodium filled valves
« Reply #3 on: January 19, 2022, 04:47:25 PM »
Seems like sodium corrodes the valve from the inside out. I had the same thing, one rolled off the table at a swap meet and broke. I have six more if you are really brave and want to run them!

gt350hr

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Re: Pros and cons of sodium filled valves
« Reply #4 on: January 19, 2022, 06:45:23 PM »
   The intakes are hollow too but not sodium filled. They don't like to hit pistons for sure.

MeanGene

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Re: Pros and cons of sodium filled valves
« Reply #5 on: January 19, 2022, 10:46:55 PM »
My 11th grade Chemistry teacher thought he would give us a practical demonstration of how reactive sodium was in contact with water- even water vapor in the air. We had one of those old eastern brick schools, 11ft ceilings with the tall windows. They had built a single floor addition behind the second floor lab, so the roof was about the height of the lab floor. He had a big chunk of sodium in a jar of oil in the back, he brings it out and cuts off a chunk the size of a quarter and says watch this. I had rained the day before, so there was a big puddle on the cafeteria roof. He tossed the chunk into the puddle, and BOOM! Shook all the windows, then lots of screaming, and a half-dozen cafeteria ladies running out the back door and across the lawn- including the principal's wife. Principal's office was about 3 doors down the hall, and the principal, who had been a tank commander in WWII, made the distance in about 45 seconds. Teach had to go to the principal's office!  :-[

oldiron.fe

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Re: Pros and cons of sodium filled valves
« Reply #6 on: January 20, 2022, 12:43:04 AM »
                                                                                                                                                              you have found the reason that hi-rise esp. and tunnel port heads were made harder to find -- many valve heads stuck in pistons  then broke lots of stuff @ 6000/7000 rpm in the 60s&early 70s                       new hollow stem-no sodium more accurate manufacture better metals----like 50 year old rods still break stuff---old over stressed parts will cause you problems sooner/later                hi-rise stuff was  drag raced to death at high rpms and dropped a lot of the valves !!!     john -oldiron                       
66' Fairlanes 427 (08/26/67- present)
66/67' Fairlanes
70' Mustang Fastback
66' Dually

Falcon67

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Re: Pros and cons of sodium filled valves
« Reply #7 on: January 20, 2022, 09:55:05 AM »
My 11th grade Chemistry teacher thought he would give us a practical demonstration of how reactive sodium was in contact with water- even water vapor in the air. We had one of those old eastern brick schools, 11ft ceilings with the tall windows. They had built a single floor addition behind the second floor lab, so the roof was about the height of the lab floor. He had a big chunk of sodium in a jar of oil in the back, he brings it out and cuts off a chunk the size of a quarter and says watch this. I had rained the day before, so there was a big puddle on the cafeteria roof. He tossed the chunk into the puddle, and BOOM! Shook all the windows, then lots of screaming, and a half-dozen cafeteria ladies running out the back door and across the lawn- including the principal's wife. Principal's office was about 3 doors down the hall, and the principal, who had been a tank commander in WWII, made the distance in about 45 seconds. Teach had to go to the principal's office!  :-[

Lab grade Potassium does about the same thing.  Ask me how I know about both, and how much fun it was to scare the sheets out of everybody in the school pool.   8)  Re: "Tim the Enchanter" LOL

>Seems like sodium corrodes the valve from the inside out.
It's highly corrosive.  Sodium/salt mixtures are being experimented with in sodium cooled fast nuclear reactors.  Lots of pros and cons to using it. 

"A disadvantage of sodium is its chemical reactivity, which requires special precautions to prevent and suppress fires. If sodium comes into contact with water it reacts to produce sodium hydroxide and hydrogen, and the hydrogen burns in contact with air. This was the case at the Monju Nuclear Power Plant in a 1995 accident. In addition, neutron capture causes it to become radioactive; albeit with a half-life of only 15 hours."

Bottom line on valves - I'd not run stock anything unless it was a bone stock low RPM deal.  Which I never do LOL.  I'd replace all the valves with modern one piece parts.
« Last Edit: January 20, 2022, 10:03:11 AM by Falcon67 »

machoneman

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Re: Pros and cons of sodium filled valves
« Reply #8 on: January 20, 2022, 12:26:32 PM »
Many older aircraft engines use the same type of valves. Cooling was a big deal with radial, air-cooled engines. I did read that on overhaul, these prone-to-break valves were replaced with solid stem or hollow stem. 
Bob Maag

GerryP

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Re: Pros and cons of sodium filled valves
« Reply #9 on: January 20, 2022, 01:20:30 PM »
I don't know all the modern day applications for sodium-filled exhaust valves, but it's not that uncommon.  I have a 2008 Saturn Sky Red Line that uses factory sodium exhaust.  I also believe the Corvette Z06 around the same time used sodium exhausts.  Same for the 427 in the Vette and Camaro.  My recollection isn't complete, but they are out there.

wowens

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Re: Pros and cons of sodium filled valves
« Reply #10 on: January 20, 2022, 02:54:42 PM »
Hey oldiron.fe
John,
How can I contact you ?
Woody Owens
Woody

Stangman

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Re: Pros and cons of sodium filled valves
« Reply #11 on: January 20, 2022, 10:18:35 PM »
What years were the valves used. Are you saying that all the old valves were sodium filled. As a for instance I have 63 427 low riser heads with 209 intakes and I believe 165 exhausts were they sodium filled. I still have them in my heads although Im not using those heads now. They probably only have 10000 miles on them. Although some spirited miles at that.

cammerfe

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Re: Pros and cons of sodium filled valves
« Reply #12 on: January 20, 2022, 11:09:58 PM »
Low-risers likely not, to my knowledge. Does anyone know more than me about it?

KS

gt350hr

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Re: Pros and cons of sodium filled valves
« Reply #13 on: January 21, 2022, 10:30:46 AM »
   "Production" valves for the low riser / CJ were not hollow or sodium filled . The only 2.09x1.66 valves that were are the C8AX valves which were originally done as C6FE valves for the 427 LeMans engines with aluminum heads. They are fully polished and the intakes have a different shape , very noticeable. All of the valves were made by Eaton and have terrible tooling marks on the ID , further complicating their durability.
   Randy
« Last Edit: January 21, 2022, 01:10:36 PM by gt350hr »

Joe-JDC

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Re: Pros and cons of sodium filled valves
« Reply #14 on: January 21, 2022, 11:10:45 AM »
Don't mean to sound like a broken record, but the biggest problem with popping the heads off the sodium filled exhaust valves was the seat pressures.  Ford printed that the seat pressures should set up at 110# for the sodium exhaust valves.  I raced a 427 with sodium exhaust valves and hollow stem intake valves for many years without a single failure.  I set the seat pressure at 110# exhaust, and 130# for the hollow stemmed intake valves.  Went through the lights at 72-7400 rpm nearly every run.  I had a local racer that just had to have my 427, and he offered me enough money that I let it go.  He took the engine to his local machine shop, did a fresh valve job.  The engine broke a valve on start-up, and ruined that cylinder.  He got all hostile with me, and claimed I sold him junk.  I asked him what his seat pressure was on the exhaust valves, and he replied with "Huh"?  They had set it up like a 460 Ford with killer seat pressures on the valve springs.  I explained the problem to him, and he never spoke to me again for over 20 years.  There are some nuances to the FE, and that is one every old timer should remember.  110# for the sodium exhaust valve seat pressure--max.  I would not use them today, since the sodium eats away the interior of the stem over time.   Joe-JDC
Joe-JDC '70GT-500