Stuck valve

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1. It did not seize when I tried it first with just oil ,
and in the first try the valve was heated longer and the head was cold.

I'm surprised this obvious point could be lost on someone who's watched the video several times.
 
Snorton74 said:
1. It did not seize when I tried it first with just oil ,
and in the first try the valve was heated longer and the head was cold.

I'm surprised this obvious point could be lost on someone who's watched the video several times.
Click to expand...

Agreed with Snorton. Also, it may not be the most controlled experiment, but it surely points to quite a bit of valuable information.

Thanks for the video, Jim!
 
comnoz said:
john robert bould said:
Jim .
The valve appeared very hot..that gas flame looked very intence... enough to carbonize most oil. What temp would a inlet valve operate at? considering all the cold wet air passing over it.
Click to expand...

I have no way of knowing the temp in a Norton, but for air cooled racing engines the intake valve head temp is commonly figured to be somewhere between 500F. and 800F. I would figure 400 to 500 for a normal Norton motor since the cylinder head itself commonly sees 400F.

When I tried the test the first time -before I got the camera out -I used an infrared temp gun and measured the intake valve head temp at about 500F. I don't know that this was real accurate. I measured it at the end of the first try with straight oil. I really didn't trust the temp gun for this so I didn't try to measure it any more. Jim
Click to expand...

An old master metalsmith like you surely have used these before, but for others, it bears repeating. Much easier to use on some things, and more accurate when it comes to shiny things like chrome header pipes, etc. "Tempsticks" http://www.tempil.com/products/tempstik-test-kits/
 
I'm not a metallurgist, but I've used a lot of these:

Broken link removed

Sorry, concours. Didn't mean to step on you. You didn't have a link when I posted.
 
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Iim,
Your oil/Stp mix is more than 25%, look at the cup, you start with approx 1/4, then its 3/4's with the STP added?
 
john robert bould said:
Iim,
Your oil/Stp mix is more than 25%, look at the cup, you start with approx 1/4, then its 3/4's with the STP added?
Click to expand...

The first time I did the test -before I pulled out the camera -I measured 4 oz. oil and 1 oz. STP.
To keep the video short I didn't bother to measure the amounts but it was still pretty close to 4 to 1.
The results of the first test were the same as when I did it with the camera.

It is true the test was not very well controlled. It was just a quick test and was only done to satisfy my own curiosity.

It did convince me enough to specify nothing but engine oil on the valve stems on the heads I build from now on. Jim
 
Ok.
We can all see the "Test" and sure enough the valve is free to start with,then when applied with the "Mix" it starts to stick.
Which we all conclude it's the added STP to the oil,
When these tests are done, "WE" all react to what we see in differant ways..because of the result ,
I personal think the "test" is not a true reflection...Because of one main fact...in a real engine the valve is on its seat for a lot more time than your test, thus it will give up more heat through valve/ seat contact..your tourch heated valve hardly sat on the seat . Do you agree?
As Chris as already stated the head was cold and the valve was extreamly hot..this never happens in real engine conditions.
Many members on this forum have proberly use in the past STP and considered the past use to have given good results, when added to the correct percentage's.
I am not concerned by the test, but as an Engineer [well i think i am :lol: ] these Tests will allways raise a question or two..but i thank you Jim for a mind provoking vidieo .
I have a head but alas no STP otherwise i would attempt this myself. Again Thank you .
 
re-Consider Jim's torch on the valve as similar to the fast heating of the exhaust valve on initial cold engine start up. Ain't much oil flow through guides as the intake has oil seal to keep it out and the exht guide never feels the intake suction as its closed then so only sees pressure out the guide on exht valve opening. STP engine honey don't consist of hi quality ingredients but mainly thickened by heat prone polymers. I use 30 wt hi detergent oil on first start up as oil is cold and I want it to flow everywhere soon as it can on cold engine clearances.
 
Here is apiece of an article I was reading about oils, ref Jim's test on stuck valve.
Stuck valve


Too many polymers is a bad thing on your valves .this article was written in 2003
 
john robert bould said:
How do these "polymers" get onto the inlet valves,when seals are fitted?
Click to expand...

Some oil will obviously get by the seal or the valve would fail from lack of lube. In my case the STP/oil mix was used for prelube as the head was assembled. It siezed in less than 5 miles.
So 2 new valves and one new guide all fitted at the same clearance as before but lubed with engine oil only and the bike is running very happily. Jim
 
I am really enjoying this post. Now for the trivia question for the day.
What does STP stand for?
 
Scientifically Treated Petroleum, and still made available EBAY! More info Google it.


boz said:
I am really enjoying this post. Now for the trivia question for the day.
What does STP stand for?
Click to expand...
 
boz said:
I am really enjoying this post. Now for the trivia question for the day.
What does STP stand for?
Click to expand...


Standard Temperature Pressure

Stone Temple Pilots
 
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