seems to be about 9.3Hz or happens 558 times per minute. I forgot to check what the idle was before I got out to look at it because it was louder since the valve cover was off. I stated it again and it went to about 1100RPMS. It looked like the knock was happening every time the cam would make a revolution and I have it on video so I can make sure. It's about the right RPM for it to be a cam problem. I noticed smoke coming from the drain ports on the head, hopefully because I have a blown head gasket and not something more serious.

...or maybe the blown gasket (if that's the case) is making the noise from the air rushing out on the compression stroke and not the exhaust stroke because there should be minimal pressure on the exhaust stroke. I did disconnect the spark and fuel from the suspect cylinder and it did get more quiet, but I also reconnected a vacuum line that came off so I'm not positive.

 

Do a compression test.

 

I probably should, but I don't have a compression tester.

 

You can rent one from AZ or what ever. Or you can pick one up from Harbor Frieght for about $13

 

well I found the problem. A part of the piston broke off and did some damage, but the cylinder walls don't feel scored as far as I can see. that doesn't mean that under the piston there isn't damage which I will hopefully be able to check this weekend if I can pull the oil pan. This would explain the metal particles in the oil. If the walls are good I am going to hone it and replace the piston/rings and just keep going. Of course it looks like the piece that broke off is mostly gone down the exhaust I imagine.



I need to get the head check to see if there was any valve or valve seat damage. It looks like the exhaust valve is sticking out more than normal.

 

Should be fine by honing the cylinder and replacing the piston/rings.

From the pic the lower end of the piston broke out and was slamming into the head. Valves look fine as I can see. You will want to have the head checked anyway to ensure a flat head surface.

Might think about rebuilding it fully and putting in some flat top pistons.

 

That was the plan and I just picked up a cylinder honer. I just have to pull the oil pan to get to the piston to pull it out.

yea it does look like it thrashed sround in there a bit. I'm a little worried because you can see where the piece was actually too big and binded on the top part of the piston and the head. I hope it didn't tweak something, but everything seems ok. Yea the cam is partially opening that exhaust valve, but I want to try and look in it to see if there is any seat damage. I'm not really concerned about the heads being straight because the gasket was seated fine.

I'm just getting another used piston/connecting rod for $55 and I'm just going to get it running again. maybe in like 20k miles or something I'll tear it down and do a full rebuild if it seems like I need it.

Oh I am going to replace teh oil pump while I'm at it seeing how these engines have a problem with it and who knows what happened ebcause exhaust was getting into the block.

 

Well here's some pictures of the aftermath of the piston/bearing halves and the condition of the journal. Can someone who works on cranks (grinds and/or polishes) let me know if that looks good enough to just polish a little and use a new bearing? I've actually sanded it a little with 400grit wetordry sand paper and applied oil to it to help (I assume it does kind of like using lube while honing a bore) and that's where I"m at now. I will take a better picture of the bottom end of the journal seeing how it's so blurry (crappy powershot 110). I'm thinking I might be able to get away with just polishing them because it doesn't look that bad, I didn't hear any grinding internally in the engine, and it would cost more than $400 to pull it out and have it polished or posibly reground. Not to mention I don't want to make this an entire rebuild and something else could be on it's way to s&#$ the bed so unless someone can convince me otherwise, I will just take my time and go over that journal by hand with 400grit (might even go to 320 because it looks like it might need it) sand paper and then move to a finer paper like 1000grit or more.

 

Metaldrgn,

Looks like your links are broken.

 

They are good, server was down. It is usually up during the day and down at night central time.