Carefully check the valve lifter adjustment. The most accurate way to do that is to bring the no. 1 cylinder up on compression then line the timing marks up and check to see if the dist. rotor is on the no. 1 cap contact. Adjust the valves on no. 1 and then turn the cank exactly one turn ( clockwise facing the end of the crank) and adjust the valves on the next cylinder in the firing order and repeat until all are done. This assures the lifters are on the heel of the cam lobes. Did you replace the cam bearings? How much material was removed when he did the deck ? Have the heads ever been planed ? Could be a bad combination. Do the head gasket fire rings protrude over the edge of the cylinder? A broken ring or ring land can make this sound, too. Check for pressure plate to bellhousing clearance. Did you use the correct pressure plate bolts? Flathead timing gears, correctly installed, do not make noise until badly worn. Good luck........... Glenn
Pretty sure mine came from Dennis Carpenter not sure brand was about 2yrs ago when I ordered them I cursed for the last 2 yrs but driving it home all by myself just now threw the country was what it's all about for me.
Some of the more unusual noises I've run across on these engines: Fuel pump knock - usually caused by a badly worn out pushrod bushing or badly worn lever. Fan hub bearings. I don't know if you're running a stock fan assembly but they can raise a racket if worn bad enough. Piston / wrist pin noise can be easily diagnosed by removing and reconnecting plug wires one at a time until you find the one that's noisy. Noise at idle is worth checking this one. Your compression pressures don't sound good. You should have 100 to 110 PSI at cranking speed with all plugs removed and throttle wide open. More that 10 pounds variation between cylinders indicates a problem.
You mentioned that you broke it in on the floor, could you have possibly dented the oil pan thus the crank hitting the dent in the pan and only audible at idle? I also agree that the compression is too low.
No on the floor was just meaning not in the car. I built a stand that held it by the motor mounts and bell housing plus held the radiator so I could do it properly plus run it a good bit over several days to make sure it was good before I put it in the car. Being my first flathead build I was and am extremely nervous
I agree with compression I didn't check it with all plugs out and throttle open I was in a crunch for time due to work and was rushing/Noth really thinking I did it no throttle and one plug at a time all 7 others installed. Wasn't looking for actual compression was really just looking for variations between cylenders. I know I gotta readjust my lifters
Glenn I'm very interested in the fuel pump pushrod bearing theory. I had forgot til you said that (I started building the motor almost 2 years ago when I first took it out then the product snowballed into suspension brakes steering etc basically about $15,000 in parts which is a lot for a guy like me) I actually was going to run a electric fuel pump originally then chose not to I recall trying to remove and replace that bushing but was unsuccessful I got it partially out tho but knocked it back in. It didn't look to damaged but me eyeballing it is definitely a stupid call. Thank you I will take a good look at it when I readjust the lifters weekend after next. (I get my daughter next weekend so won't be working on it)