When Things Go Wrong!!!

[c.o.]

Just the messenger... this is a thread brought to you by Slojo.....

This exhaust valve head fell of at a traffic light while idling. The valve appears to have a black hard coat stem and a part number stamped on the stem by the keeper groove as an identifier the number is 56012. Does anyone know who the manufacture is?

joe

[c.o.]

Whoops..... I neglected to mention that we're talking about a '48 EL.... and that busted valve in the top of the piston is a horrific shot!!!!

[Jerry Wieland]

Actually for dropping a valve that is relatively minor damage. It probably just locked the engine up. At RPM it is a totally different story. It never is good but the head is repairable and the cylinder looks undamaged.

Looks like the engine was burning oil or running rich. One valve wasn't seating very good.

I cannot help ID the valve but Rowe is a big producer of valve hardware.

Jerry

[Tom Lovejoy]

My brother in laws Sportster did that at speed, 30 years ago. It's still in his shed, he has not fixed it yet.

[Slojo]

I bought the bike about ten years ago and the motor already had been rebuilt . It has a Jim's main shaft sticking out with his name laser etched on the end. Although it ran well I never liked the sound of the motor, (to much top end noise) and figured eventfully it would come out for a rebuild and conversation to hydraulic lifters. The valve guides are Rowe but the valve has not been identified yet.

joe

[exeric]

I'll be following this thread with great interest as I have to do the heads on my '48 motor. Is there a consensus on who makes the best valves, guides, and springs?

[Slojo]

I have not experienced spring failure using stock springs. These are not Indy motors. The material fatigue with this valve must have been a faulty manufacturing process. Either the friction weld or the subsequent heat treat, I believe the heat treat machine/process is at fault. Typically these problems are caught during manufacturing and this valve probably slipped by Q.C.

Heat treating valves is most likely accomplished by an induction heat treat process. "Basically", a valve stem is inserted into a coil and a high frequency charge of electricity is pushed through the coil for a few seconds exciting the molecular structure of the valve stem to a point where the metal lights up from friction (Atoms bouncing of each other) within the make up of the metal followed by a quenching process.

I am not a qualified metallurgist !

joe

[Robert Luland]

Heat treating valves is most likely accomplished by an induction heat treat process. "Basically", a valve stem is inserted into a coil and a high frequency charge of electricity is pushed through the coil for a few seconds exciting the molecular structure of the valve stem to a point where the metal lights up from friction (Atoms bouncing of each other) within the make up of the metal followed by a quenching process.

Joe, that is pure sex to a motor head!

[T. Cotten]

I am haveing trouble viewing the pics Folks,
so please set me straight:

You blame the valve?

....Cotten

[mcarver]

At least that valve head didn't pass into the lower end..... that would have made a noise. Was it the valve that failed or did the valve spring fail and drop the valve onto the piston which then broke the head off the stem?