I dropped a valve last month at Watkins Glen. Now my schedule for a new engine has been accelerated. Its always important to know how your engine was built. Just a few pics. The cylinder wall was also broken.
Mark
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Another pic.
Perhaps someone can chime in here, but I thought the joining line for the stem to the valve head was closer to the valve than what is showing in this photo?
Larry
Larry
That may be a secondary break after the valve and stem dropped into the cylinder.
Mark - Is this the only break, or do you also have a piece of stem somewhere, besides the piece still in the retainer?
"Inquiring minds want to know"
Mark - Is this the only break, or do you also have a piece of stem somewhere, besides the piece still in the retainer?
"Inquiring minds want to know"
The stem is still in the head.
I had been planning on rebuilding it for some time, and now I get my chance. There is always a need for more speed.
Mark
I had been planning on rebuilding it for some time, and now I get my chance. There is always a need for more speed.
Mark
quote:That may be a secondary break after the valve and stem dropped into the cylinder.
Okay, then you are surmising this valve ...did not...break at the weld line, but instead lost a keeper at the top of the stem, fell down into the chamber and was broken as a result?
To see if that is the case, then we need to see the top portion of the stem.
Larry
The keeper is still on the valve stem. I was at 5600 rpm when it happened.
Mark
Mark
quote:The keeper is still on the valve stem.
Okay, I am still confused.
It did not lose a keeper and drop into the cylinder, and I really think the break point is NOT at the weld line.
Anyone going to jump in here and explain this to me?
Larry
Mark,
What year is the engine (I see it's open chamber)? How many miles? Has it ever been apart?
Your valve head appears to have a shorter neck than the one from my '71 (see pic below).
John
Pic of the original exhaust valve from my '71 after 106k miles. This is the first time that the cylinder heads have been off.
What year is the engine (I see it's open chamber)? How many miles? Has it ever been apart?
Your valve head appears to have a shorter neck than the one from my '71 (see pic below).
John
Pic of the original exhaust valve from my '71 after 106k miles. This is the first time that the cylinder heads have been off.
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Its a '73 with about 40K on it. Is has been apart prior to my purchase. I tried to get some build info from the seller and engine builder but no such luck. This event has always been on my mind. My valve has a soother taper that the one you show.
My new engine will have HD valves.
Mark
My new engine will have HD valves.
Mark
quote:My new engine will have HD valves.
Just make sure they are true, one-piece stainless steel pieces.
Larry
The new ones are are definately one piece severe duty SS valves.
Mark
Mark
quote:My valve has a soother taper that the one you show.
Mine is eroded from all the miles on it and was probably smoother when it was new.
John