In my Howell TBI install thread (see my sig) I've mentioned a misfire and lifter tick noise a couple times that sounded like the driver side #1 cylinder. Had time tonight to remove the valve cover and found some pretty concerning things.
Exhaust valve is on the left, intake valve on the right. I discovered the intake rocker arm was pretty loose, so I decided to tear things down a bit to figure out why. Exhaust side has no issues from what I could tell:
Both rocker bolts were tight so that wasn't the problem. I took both bolts out and discovered what has to be a lot of black gasket maker on the exhaust rocker bolt threads:
The exhaust rocker bolt hole had a ton of rubbery gunk in it too, so I cleaned it all out. Unfortunately the exhaust side is not the one making all the noise, it's the intake side!:
I also discovered the rocker bridge between the exhaust and intake rockers was bent. The other 3 bridges on that head are all perfectly straight. Not sure what caused that bridge to bend, but I took it apart and hammered it flat again. I wonder if maybe it was assembled already bent and maybe caused increased wear on the intake side to make it so loose.
UPDATE: Based on some of the other bridges I took out, they were bent when the rocker arm bolts were overtorqued. Tapping them straight with a hammer on a flat surface fixed those issues.
The exhaust side on the left here was bolted in properly so the exhaust rocker was straight and made good contact with the top of the valve, but the intake rocker had the bent side of the bridge causing the rocker to angle a bit odd on the top of the valve.
Maybe the movement of the intake lifter, pushrod, and rocker arm somehow caused that bridge to bend? I doubt it, but not ruling anything out.
I've never seen that before. I also noticed what feels like increased wear on the top of the intake valve, but it might just be my imagination.
Could be a bad cam lobe too I suppose, but I find it odd it's just that intake side on the #1 cylinder with that bent bridge. I put everything back together after cleaning, hammering the bridge straight, and inspecting everything again, but that intake rocker is still just as loose.
I also removed both push rods and they're both perfectly identical, straight and unclogged, so that wasn't affected.
Nor does it look like there's any increased wear on the intake rocker arm, either underneath where the pushrod contacts it, nor where the retainer sits in the rocker, nor where the rocker contacts the top of the valve.
Neither the intake bolt, nor the hole had any rubbery crap on it, so not sure what the hell someone did, nor why, on that exhaust side with all the rubbery gunk on it.
I'm now wondering if that rubbery crap just got into the intake lifter and clogged it, or if I have more crap circulating, or if any other rocker bolts have any crap on them.
Odd though, only the exhaust bolt had that rubbery crud and the problem-child intake-side didn't.
I'll run some engine gunk cleaner thru it, change the oil and filter again, and see if maybe it's just the lifter or not.
If not, I'll have to remove the intake and see if the lifter and / or cam lobe are toast.
Anyone care to chime in here with their thoughts?