Technical Knocking Flathead 6

I am new to flathead engines, and fairly new to carb engines in general. I just bought this 1950 Ford with a flathead 6. Once the car is moving, the knocking seems to die down, but at idle it is very noticeable. I have parts in the mail to do a tune-up, and a carb rebuild kit from MAC's. I know there are fuel issues because it stutters at low speeds, and surges at part throttle. You can even see in the video when the air filter is shaking from the engine stuttering to bad. The biggest clue is the fuel leaking out of the carb, but I know that has nothing to do with the knock. I just changed the oil, and it made it a little quieter but it is still there. There also seems to be a lot of blow-by coming out of the oil fill. Here is a video to show what I'm talking about.

 

Can't really hear a knock, but with blowby it's probably piston slap and/or a pin.

 

Try pulling spark plug wires, one at a time and see if you can change or isolate the tapping sound to a particular cylinder. Could be a number of things. As stated above, piston or pin, fuel pump, tappet noise, timing gear, etc. you might also consider pulling the side covers, where the tappets are located if you don't find the source elsewhere.

Ray

 

I attempted to pull off a spark plug wire and as soon as I touched one I got electrocuted through my gloves. I will wait until I get all the tune-up parts, then start diagnosing from there.

I guess I would call it a tick, rather than a knock.

 

exhaust leak maybe.....

 

After listening to your video I would suspect lifter noise, perhaps from a stuck valve that's letting a lifter bounce. You didn't let it idle, but it sounds like it's missing like it would if you had a valve that wasn't closing. Start with pulling off plug wires one by one as noted in Hnstray's post; use a pliers with insulated handles and don't lean on the fender or lay your arms on any metal when you pull the wire and you should be able to avoid getting zapped. If you find one cylinder that isn't firing pull that plug and check plug condition first, and compression second. You may be able to see the valves through the plug hole to determine if they're closing. That's how we do it on the four bangers.....

 

you're lucky... does NOT sound like a rod knock...

 

Thanks for the pointers, everyone. I will try to look it over in the next few days because I have to get knee surgery on Wednesday and will be off my feet for a little while.

 

How is your oil pressure? That will tell you if your bearings are ok. It sounds like the valves need adjusting and there may be a wrist pin noise in there. Try the valve adjustment first.

On Chrysler flathead sixes you can remove the right wheel and go in thru an access plate in the inner fender. Ford may have something similar. Look for a removable panel in the inner fender.