'64 F-100 292 V8, 4 spd, 3.89 rear end

Had my slick loaded down and driving a good distance on the highway this weekend, doing about 60-65 mph the whole way when I heard a somewhat loud "crack!" and what sounded like a coupe of peices rattling around for a second afterward. The truck still ran fine, but I pulled off at the next exit and when I came to a stop the engine was running really rough (like it had a miss). I shut her down and did a visual check, everything seemed to be in order. I was 100 miles from home and 70 miles from where I had to go, So I said hell with it, fired it back up and kept going. I managed to get her to my destination, although I had to listen to a sickening "slapping" sound from the valvetrain the whole way. Sounded like a real bad exhaust leak, as it only made noise under load. The sound never got worse, even though I had to keep going another 70 miles.

I took the valve covers off and all the rocker arms/push rods were all tight. I cranked the engine over a few times with the coil disconnected and everything is getting oil and moving like it should, all parts were in tact. I fired it up with the covers off and it wasn't making that slapping noise, but still had the miss (sound came back when I put the covers back on). I pulled a few plug wires off and found that the miss is coming from the driver front cylinder, the same one the noise is coming from (not sure which number that one is), although it is still getting spark. I had limited tools with me so I didn't take anything else apart. I had to leave it at my destination this weekend until I can get back down there to fix it. I suspect maybe a lifter is busted or something?? Not sure, but I don't think these are hydraulic lifters are they? Anyone have any ideas what I'm facing here?

Sorry for the length, just wanted to make sure I had all the details in there.

 

The front driver side should be #5 if they are numbered the same as everything else. If you have a compression guage I strongly suggest you take it with you when you go recover her. Look at the spark plug on that cylinder for any mechanical damage. Check the cylinder and those around it for the same psi or within 10% of one another. What RPM does the engine turn at 60-65 MPH?

 

I wish I knew the RPM at that speed - I bet it's pretty high...I'll check the compression and pull the plug when I get back there.

Thanks for the input.

 

No hydraulic lifters in 292's.

Don't forget: You can go over to Green Sales if you need illustrations of the internal engine parts.

Talk to Dave, he's the most experienced guy they have, and knows these engines.

 

UPDATE - I finally got down to retrieve my Slick this past weekend; Pulled the plugs and did a compression test on the first two cylinders - 100 psi each on the dot. Then I looked at the plugs...they are filthy. That's why it's running like crap. The "slapping" sound is just an exhaust leak (I could feel it with my hand). I'm guessing the clunk I heard when this all happened must have been a chunk of dirt or rust coming off. All of this stuff converged at once and made me think I blew something up! Good news is, I think if I replace the valve seals, the plugs won't foul out and she'll run good for a while.