Engine knock

[57 Ford Kustom]

Ecode, the wire melted right at the plug, so hot the when I went to pull the wire it slipped right off the crimp. Like I said, the plug was almost white it is so hot in that cylinder. Pulled a couple others and they were normal. It is in the cylinder that is knocking, so I don't think it's the piston, rod, or wrist pin. I think that I may have a bad exhaust valve or it isn't seating fully. I may be wrong, that is why I'm fishing for advise, or direction. Day's like this really make me miss my Dad. Tim

[Ecode70D]

Tim
     Just for fun, you can take a compression test.  Don't forget to keep the throttle plate open when you do it.  That could put the exhaust valve question to rest.
      The good thing is that this site is loaded with experts with many many years of experience.       Over the years just about every conceivable problem has occurred and was dealt with.
       Hang in there...   I'm certain that someone on this site will give you the answer.
     Jay
         
   

[57 Ford Kustom]

Encode, I went out and cranked the engine to check the valve movement, it worked like the others exempt, occasionally the exhaust valve would not return fully, I am guessing that would be a valve guild issue ? Maybe the valve doesn't seat all the time. I only say this because my wife had a Taurus that actually burnt the end right off the spark plug, it turned out to be a chipped exhaust valve. Just reaching at this point. Tim

[BWhitmore]

A burned exhaust valve will not cause a knock, unless you have a bent valve/bent push rod or damaged rocker arm.  You may want to simply replace the bad spark plug and the burned spark plug wire and see what happens.  Also there is a difference between an engine knock and a mis-fire.  If you still suspect that you have a burned exhaust valve it is recommended that you do a cylinder leak down test.  This test involves bringing the piston to top dead center with both valves closed and injecting air into the cylinder through the spark plug hole.  If you have a burned or leaking exhaust valve you will hear air coming through the exhaust pipe.  If you hear air coming through the carburetor then you have a leaky intake valve. 

[57 Ford Kustom]

I have determined that the valve isn't seating, I am not sure if it is a bent valve or sticking valve. If I turn the engine over the exhaust valve sticks open briefly giving the appearance that the rocker arm is jumping on the close stroke. That may be why the knocking noise is louder up in the intake rather then in the bottom end. Maybe wishful thinking, but for now I'll roll it in the garage pull the heads, and find a shop to do a valve job on it. Thanks for the input guys! Bill, this is the second set of plug wires in a week.

[57 Ford Kustom]

Well, I found a shop that will do a valve job on my heads this week. 185 dollars plus parts, I will have them drill and tap for 3/8 rocker arm studs also, and get rid of those 5/16 pressed in ones. I'm glad I went ahead and pulled the heads, I found cylinders 6&7 exhaust valves had been leaking by also! Thanks, Tim

[Tom S]

Well, I found a shop that will do a valve job on my heads this week. 185 dollars plus parts ...

Both heads?  (I hope!)

[57 Ford Kustom]

Both heads Tom.

[57 Ford Kustom]

Well, got the report back on my heads. Cylinder 4 had a worn valve guide, he also had to replace 2 rocker arm studs. He said he had to resurface all the exhaust valves because they were pitted. Over all he said they were in good shape for an engine that was 45 yrs old and never been touched prior to this. Still crossing my fingers that I won't have to rebuild the bottom end this summer, time will tell.

[Zapato]

lower end often follows top end, but not always. good luck.

Zap-

[57 Ford Kustom]

Thanks Zap, I guess that getting it right is more important than driving it. After all there are guys on here that haven't driven theirs in years!

[Zapato]

You are absolutely right. Last time I drove a 57 was my last night home before I shipped out to Nam.  Now been gathering stuff for years to build my car and hopefully one of these days I'll start building my current one. You're dealing with minor setbacks and your dad would be proud how your honoring his legacy. And that legacy isn't just that well organized pile of metal but you and your kids are way up on that list.

Zap-

[57 Ford Kustom]

Thanks Zap, sometimes I need to slow down and listen to a voice of reason! Thanks, Tim

[57 Ford Kustom]

You are right Zap, I got the heads back, and the guy at the machine shop told me how to figure out if my lower end needs a rebuild. It does, so out with the engine and on with the rebuild. Is it easier to pull engine and trans or just engine? Tim

[Ecode70D]

/quote]

In my opinion it is easier to pull the engine.  If if is an automatic, don't forget to replace the front seal on the transmission while it is apart.  For a couple of bucks, that's cheap insurance.