Loud Engine Knocking?

[jayoldschool]

Good vid references. I will say that the rod knock that I have experienced is a deeper tone than that. Would probably have to do with the V configuration and much more block material than the boxer engine in the Subie...

[77CDV]

Well, heck, Dope, November doesn't seem to be your month! Here's hoping things are just sticking a little from the car sitting so much. I'd really hate to see major engine work needed. Let us know what happens.

[DopeStar 156]

It sounds like the rod knock video......

[flux1414]

It sounds like the rod knock video......

That sucks dude, I feel for ya. Sounds like you may get to experience the joy of pulling and rebuilding an engine...

[DopeStar 156]

Well considering I can't drive it anywhere or tow it, I'm kinda screwed here. How hard is it to do something like this?

[jayoldschool]

You can drive it to a garage. It may or may not seize up on the way.

If it were me, I would do the following. Pour in a quart of trans fluid. Run the engine, get it up to temp. If it is a sticking lifter, the trans fluid will free it up. If you have wiped a lobe off the cam, the tick will still be there. If it is rod knock, the noise will be there. Turn the engine off, jack it up, and drain your oil. Carefully examine the oil for metal particles or a "silver-y" sheen. This will be the remains of the soft bearing material. Remove the oil filter and let it drain. Cut it open, and unfold the filter material. Look for metal particles. If you find metal in the oil and/or filter, you have lost a bearing, and the engine will need a tear down. You can pull the pan (have to remove the engine mount bolts and jack up the engine a few inches) and check the rods on the crank. If you have wiped or spun a bearing, the rod will be loose on the crank. Engine must come out, crank must be turned, and new bearings go in.

[DopeStar 156]

[jayoldschool]

That sounds like exhaust leak, not knocking. I know, the audio is bad, and I'm sure it is much easier to tell in person...

[DopeStar 156]

It has that already hahahaha. It'd be awesome if that's all it is but I dunno.

[flux1414]

I agree with Jay, it sounds a lot like exhaust. My '80 was without manifold gaskets and it sounded quite similar. It's tough to really tell with the video though...you may be lucky yet

[Stingroo]

You know what it really reminds me of?

Speed Buggy.

YouTube- speed buggy intro

[jayoldschool]

Dope, engine knock on a cast iron V8 sounds like a 5lb sledghammer hitting a manhole cover. Does that make sense? It is really deep, no echo, low frequency.

[csbuckn]

that almost sounds to fast to be a bearing.

[sven914]

I agree, it sounds too high to be a main bearing. It does sound right to be piston slap, which isn't harmful to the engine, just really annoying. If you hear what sounds like a double tap when you feather the gas, then piston slap is the problem. Also if the noise goes away when the engine warms up, it be a sign of piston slap, because as the metal expands with the heat, the piston fits the bore better.

This is what low end rod knock sounds like on a real engine (be patient it'll eventually start):

http://www.youtube.com/watch?v=FksrdMc3lZU

[DopeStar 156]

So you think I blew a manifold gasket or something? How can I really be sure? I'll change the oil this weekend and let it run for a while and see if it straightens out. God i hope so, I don't have the heart to dump this car.....