My '85 MGM, "Maisa"

[sly]

The rattle doesn't sound like lifter tick though. Sounds more like spark knock. I would just double check the timing to make sure it's not moved for some weird reason. If it's still at 10, try backing it down to 2 and see if it clears up. I know some of the truck engines prefer 2 base.

[Arquemann]

I don't think this story will have a happy ending...

I verified timing again and played with it some more, doesn't change the rattle. Also popped open the driver side valve cover, nothing loose under there either.
The engine ran for about ~30 minutes more while I was playing around with it, the rattle might be getting slightly louder, but a faint knocking sound appeared and the engine is shaking alot more while idling.

I'll drop the oil tomorrow, this evening I'll just wallow in foreboding sadness.

[sly]

engine shaking makes me think misfire. Bad plug, plug wire, rotor/cap... definitely something to check.

[gadget73]

The rockers are just tightened until they hit torque. Its not a Chevy, they don't do the turn past the point where it stops clacking thing Fords you have to measure preload, something like 20-60 thousandths of an inch past zero lash, or like 1/2 to 1 1/4 turns past zero lash to the 20 ft-lb or whatever the spec is. If it turns more or less than that, you need different pushrods, or possibly shims depending which direction the problem is. Factory rockers, cam, stock replacement lifters, stock heads, and stock replacment head gaskets I'd expect to all play just fine though

the pushrods are a different length from roller to flat tappet though, I'm just assuming you are using the pushrods fro a roller cam.


kinda sounds valvetrain adjustment related to me.

[Arquemann]

Oil is quite metallic, some glitter set into the bottom of the drain pan, dunno if it's alot or not for first break-in oil.
I cut open the oil filter, no chunks, no flakes and barely even glittery. So most of the shiny bits was mixed in the oil.
Dunno what to think of this.

For my next move I think I'll get another can of oil and go through the rocker adjustment with the engine running. I'll mark the positions of the rocker bolts beforehand.
The factory preload setting procedure is kinda ass to do in the car, besides, it went nicely when I did on the engine stand. What I don't understand is how the lifters being pumped up or not would affect the end result. Surely the lifter would bleed down before the valve opens.

EDIT: Also pulled a few plugs and did a compression test on nr. 2 & 3 (what for having two hands a shit tester) Plugs look mint, barely any variation and compression was around 140 for both. Before the engine started shaking yesterday, it had ran very smooth and the exhaust note has always been very smooth.

Zoom for shinies:

[sly]

The oil looks "normal" to me from what I've seen on first run break-in. Maybe even less shiny than some. I know the initial oil change on my generator looked worse than this. Even the last oil change still had glitter, but I'm also still less than 25 hours on it (barely to 10 hours) after 3 years of maintenance runs and one power outage that lasted a good while (4+ hours). Runs like a top though. So I'm sure you're fine right now.

[gadget73]

lifter bleed-down is unrelated. There is a spring inside, that will keep the lifter at max length and thats all you need for preload.

do not try to set this while running. It does not work. There is no means to keep the bolts from rotating back out, the only way to do this is to set the bolts to correct torque.

If the preload was right when you did it on the stand, its still right.

[Arquemann]

Fine, I guess. Still not quite sure on the adjustment basis on these bolt on rockers, so I'll take your word for it.
As you said, I'm using all original or stock replacement parts on the valvetrain.

I guess I'll remove the timing cover next. If I can't find anything wrong under there, it's engine out. Might pop off the intake before that, maybe.
Too bad I already poured a new can of oil in.

[Arquemann]

Opened the timing cover and intake, nothing seems out of place or broken. All lifters seem fine and none sit too low in the bores or such.
Time to pull the engine! After I pull myself together first...

[friskyfrankie]

Can you not simply drive the car, as is and see how it performs and what the oil looks like after a reasonable period of time?

[sly]

Get the oil pan off and if there's nothing weird, I'd say just shove it back in and drive it a while and see if it quiets down after 500-1000 miles.

[Arquemann]

No, I'm taking out the engine. For fuck's sake I can hear the rattle from across the yard and over the exhaust with my face next to the tailpipe.
Those are not healthy gasoline engine noises and bad noises rarely go away without harm. I'm not driving it like that. It'd be nonsensical to have a "rebuilt" engine make that kind noise and try to play it off as normal.

I am not financially or mentally in the position to grenade a 302 because "maybe the sound will go away". I'm in Finland and here you can't find small blocks in every attic and behind every tree stump.

No. Just no.

[87gtVIC]

That is unfortunate. I do hope you find what is going on. Not ever finding out would drive me crazy.

I had to chuckle at your last comment:

I'm in Finland and here you can't find small blocks in every attic and behind every tree stump.

I have two 5.0s up in a barn lol.

[sly]

Do you have a borescope? If so, scope the tops of the pistons and check the edges to see if there's an impression of the heads that would indicate piston slap. Hopefully you don't have to pull the heads off.

[Arquemann]

Do you have a borescope? If so, scope the tops of the pistons and check the edges to see if there's an impression of the heads that would indicate piston slap. Hopefully you don't have to pull the heads off.

I do have one, but its more of a generic use one, resolution is garbage and it does poorly in low light. But I can say there's still a piston in every hole, no big dents or chunks missing off them and no extra bits laying on top.