The Ford Barn

rjlester · 04-12-2026, 10:53 PM

A few days ago I fired up my 1954 Meteor with an original 255 Flathead (Canada got the flathead one more year). It was parked all winter. I did start it a couple of times over the winter. No issues.

Last night on the way home from town, I slowed for an intersection and I heard a noticeable rattle coming from the engine. I had a sticky valve a couple years ago so I figured this was the same thing. Previous noisy valve went away with some seafoam in the oil and a drive down the road. Now after messing with it today, I'm not so sure. I added seafoam, drove it for about a half hour and it has not gone away.

I did a compression test, and I have compression on all 8 cylinders. They have always been a bit low, but it runs amazingly well, they were all between 75 and 90 with the throttle cracked open a little. If it was a sticky valve, wouldn't I lack compression in one cylinder?

The funny thing is, I have great oil pressure, no different than before. Stock gauge has always worked and I show over 40psi while driving, over 20 idling.

I used a broomstick to my ear and it is definitely coming from the drivers side. You can actually feel the noise (in my hands) holding the broomstick against the lower two head bolts at the bottom of cylinder 7. So, I suspect cylinder 7. The head bolts above the spark plug do not reflect the same amount of noise. Pulling the spark plug wire off all of the plugs while running makes no difference to the sound.

I can see all of the valves opening and closing through the spark plug holes. Sprayed seafoam down all of the valve stems. No change. I suspect a wrist pin. The noise is there at any RPM, just gets louder with more speed. When you come off the throttle it almost seems louder momentarily.

Any ideas? I'm stumped with having good oil pressure. Worried it's a wrist pin.

04-12-2026, 10:53 PM	#1
rjlester Senior Member Join Date: Aug 2022 Posts: 291	My flathead started knocking. A few days ago I fired up my 1954 Meteor with an original 255 Flathead (Canada got the flathead one more year). It was parked all winter. I did start it a couple of times over the winter. No issues. Last night on the way home from town, I slowed for an intersection and I heard a noticeable rattle coming from the engine. I had a sticky valve a couple years ago so I figured this was the same thing. Previous noisy valve went away with some seafoam in the oil and a drive down the road. Now after messing with it today, I'm not so sure. I added seafoam, drove it for about a half hour and it has not gone away. I did a compression test, and I have compression on all 8 cylinders. They have always been a bit low, but it runs amazingly well, they were all between 75 and 90 with the throttle cracked open a little. If it was a sticky valve, wouldn't I lack compression in one cylinder? The funny thing is, I have great oil pressure, no different than before. Stock gauge has always worked and I show over 40psi while driving, over 20 idling. I used a broomstick to my ear and it is definitely coming from the drivers side. You can actually feel the noise (in my hands) holding the broomstick against the lower two head bolts at the bottom of cylinder 7. So, I suspect cylinder 7. The head bolts above the spark plug do not reflect the same amount of noise. Pulling the spark plug wire off all of the plugs while running makes no difference to the sound. I can see all of the valves opening and closing through the spark plug holes. Sprayed seafoam down all of the valve stems. No change. I suspect a wrist pin. The noise is there at any RPM, just gets louder with more speed. When you come off the throttle it almost seems louder momentarily. Any ideas? I'm stumped with having good oil pressure. Worried it's a wrist pin.