My newly rebuilt 225 sounds _almost_ as if it has a knock. It's a hollow tonk, tonk, tonk, tonk that seems almost to move around. It seems too low/hollow to be right for a rod. And sometimes it even changes from tonk, tonk, tonk to tonka, tonka, tonka (at low RPM), which doesn't sound like any rod knock I've ever heard.

Once I was listening back and forth on the passenger side when I found a spot just rear of the alternator where it got quite loud. For a while I thought it was coming from the alternator. . . can't be sure it isn't. But listening from the front I heard nothing.

There are two small spots where I can hear it with the stethoscope. Low front (block) on the drivers side - a spot a couple inches across - and high rear (head) on the passenger side. Despite the low pitch I tried pulling the dip stick. That wasn't it.

Oh, with the stethoscope the alternator does sound a bit like it's full of gravel.

I really hate not knowing what a noise is. Any great suggestions as to where this irritant originates?

Check for proper valve lash and interference with the rocker cover. Mine was making a funny tick/knock, and I wrote it off to being solid lifters (I was used to hydraulics). Turns out a rocker arm was just /barely/ tapping the valve cover.

mine does that when im 3 quarts low on oil! it sounds like a diesel with all that chater and my open exhaust.

Holy Cow!!! Needless abuse!

D/W

_________________

If it ain't broke, fix it!

I'll name that sound in TWO notes!

Wrist pins.

Could also be the fuel pump arm, but I'm laying my bet on wrist pins. Kermit does that, too. The sound is very subtle, it's not pronounced and doesn't get louder (clackety clack) with RPM like a bad rod bearing does. You can run it forever like that, just gives it a bit of personality!

D/W

_________________

If it ain't broke, fix it!

Loosen and take off all the drive belts then run it and listen, if the knock is still there then you've got internal problems, probably a timing chain.

Naw, I wouldn't suspect the timing chain to be associated with a cyclic knocking (although I guess anything's possible). I forgot to ask you, Luthastro, if you replaced the pistons. I do agree about the belts, though. I've heard belts that have sounded as bad as a rod knocking.

D/W

_________________

If it ain't broke, fix it!

Thanks. That's easy enough to check out.

Thanks. It's 1/8 inch above full.

Thanks. As a matter of fact, I haven't detected the sound when it's revved up.

Fuel pump. I thought about that, but I don't understand how that would work. They're always tight against the cam. At least this one and every other one I ever came across are.

Personality? Just what I have been searching for!

Exactly. My cow gets all the oil it wants.

Interesting. New chain and gears, but. . .

Thanks

It's a longshot, but I've seen the torque converter inspection plate warps enough to just touch the flex plate bolts - it then makes a nasty loud knock...

I overlooked the new motor part and agree that it could be the converter bolts or a cracked flexplate if it is an automatic transmission. The noise can easily come from there and if it is a recent install the chances are that is the problem, hope it is a loose bolt but more than likely not. The sound you describe seems to be a stamped metal part getting hit thats why I said timing chain but a new motor should not be make those sounds. I have seen too much thrust clearance on the crankshaft make the same sound, the flywheel bolts hit the belly pan but let's not think those things, bad karma.

Wow. The first 3 words. That's what I'm thinking; I hear nothing at all from inside the car. But haven't got back to checking it. Thrust clearance was on spec.

Thanks