I'll be honest here, I don't know beans about preload. I'm willing to learn. But before I task my brain have you guys listened to the sound? Would a preload issue make that racket? It sounds really, really loud. Would it come and go (also hear video from previous day... No noise). It comes and goes in the space of a few miles! I know a phone video isn't ideal... But that sound can be heard a half block away.

 

Spring load is different from lifter prelaod. They are independent of each other

Springs load is tested on a bench. With a special tool:



Lifter preload is how much the lifter cup is pushed down when the lifter is off the cam lobe.

 

I emailed you.

My testing so far was to just check each lifter to be sure it is not collapsed, then putting the cylinders at too dead center and observing no wiggle on the push rods. Meaning, I suppose, that what I did was a caveman lifter preload test.

Since the head was swapped (along with everything in it, rockers Springs, etc.) and I didn't have this sound on the other engines or even this one before, I doubt spring load is the issue.

Also, each of the rockers have the rod cups in place and the rods are smooth and straight.

Also for historical purposes, I replaced the rod bearings and did not have rod knock as tested with a screw driver and my ears.

I am beginning to wonder whether I have a bad cam or bent crank. I have looked at all of the rod caps and see no signs that they are hitting. When I replaced the rod bearings, I did note a smooth spot on the bottom of number 7, which makes sense because it was pushing against a very hard obstruction (bolt).

 

Since you are still scratching your head, I'll throw this out there. I went back to listen to the tick again on your video. While listening, my father overhead the tick. Without any knowledge of what type vehicle it was, he instantly commented that it sounds like sparkplug arcing. He seemed sure about it. You might want check that, if you haven't already.

 

I will. Hey. Maybe that explains why it ticks sometimes and then is silent others. If I didn't have it on video I wouldn't believe that it was ever silent.

I'll check that first.

If the weather holds here is the plan this weekend:

Check for spark plug arc. I pray that's it.

Since I have replaced literally everything except the cam and crank I am going to pull the engine. Then, starting with the valve covers, pull everything off of it. Rockers, lifters, pistons, everything until I find a part that is catching or clicking.

If I do all that and still don't have a culprit, I am going to reassemble it using the overhaul manual and some info Acamoto shared with me, with new lifters, gaskets, etc and my last set of bearings. If that doesn't fix it, it can just tick itself to death.

 

The fact that the tick goes away and comes back, I feel, will vindicate the culprit. I just can't think what would do that and I have disassembled and reassembled this and other engines many times. I guess I'm having a mental "engine block".

That caked piston face also still haunts me. I feel it has to do with it, too, but I can't put my finger on it.

 

If it was an arcing plug, wouldn't the noise have stopped when you pulled the plug leads?
On the chance that it IS a plug issue, have you tried changing the plugs on that head?

 

I have; they are two weeks old with maybe 20 miles on them. I have pulled the plug wires individually, but I have always put the plugs right back where they came from.

I'm pessimistic but that's any easy thing to check so it is first on my list.

 

New head gaskets arrived today so no going back now. Redone heads will be ready in the morning.

Misery weekend. Again.

I just started the rover. Smooth as glass no codes. No tick. I idled for about five minutes and there it came. Ugh.

Spark plugs seem to be doing the job and I don't detect anything amiss b when it gets dark I'll take another look. It still sounds like it is coming from inside the engine.

Bastard Rover!!!!!

 

Charlie,

I really admire your persistence on this one. Just have to throw this out there as an outsider looking in... Have you checked EVERYTHING that could be a simple explanation? Since I can't tell direction of sound in your videos... Is there any chance it's something as stupid as:
-something stuck on your serpentine belt/something wrong with a pulley
-any other pulley/spinning part that is less internal than you have been looking
-something wrong with your flywheel or related spinning components?
-broken motor mount???

I always try to step back and start with the simplest possible solution. I realize you are being incredibly thorough, but sometimes the simple things are forgotten. Best of luck!