What killed it? Something in the engine.

[68442]

If you read my other post I was having lean conditions and knock. Hit 5k and the engine lost power etc. Compression test showed #1 40 psi below the others. After the compression test the motor was REALLY knocking. Pulled the head and heres what was in #1. All valves look ok. All spark plug electrodes accounted for. To me it looks like a valve keeper, but those all seem to be there. I assume its rebuild or different motor time. The way it was knocking it couldn't have been this little shard doing that?

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[Jeff99GS]

Looks like detonation

 

[68442]

Yea, that and that little turd there on the piston. I suspect my fuel pump was weak, showed good at idle but must have fallen behind while getting on it. I removed the cams, all valve keepers are there.

 

[soccerplayaz16]

hmmm do you have a wideband?

 

[knochgoon24]

So what do the walls look like?

 

[DeNoZZo]

Just out of curiosity, how many miles are on your motor. I changed the plugs the other day and noticed my pistons were not near as rough looking (140k). Or is that from that piece bouncing around?

 

[Jeff99GS]

I wouldn't be surprised if you accidentally dropped something in the spark plug hole. When you pulled out the plug, the piece probably fell in

It almost looks like a philips screw head in the one picture?

what do the rest of your cylinders look like? Pics?

 

[68442]

Next time its up and running it'll have a wideband on it. The motor had 140k on it, the walls are baby smooth. I have no idea what it is, looks like a valve keeper/lock to me. It must have been in there since I put the head on 400 miles ago. That piston is the only one that looks like that.

 

[soccerplayaz16]

such a shame ### now you have to build it what are your plans? im real suprised it didnt do any damage to the valves....you might want to check them out anyway just to be safe

 

[68442]

I'm just going to yank the motor, the walls are clean and it "appears" the valves/head is ok. Before I pulled the motor its psi was 90 without oil, rest were 140-150. This spring they were all equal. I'll look it all over again later.

It really sounded like a rod knock right before I tore it apart.

 

[Defiant]

Wow, nice one.
No, that's not from knock. You had something floating around in there, and for a pretty long time. And you're saying the head's not effed up? Hard to believe. Check your valve seats, whatever had been there may not have cleared on its first try. And check your exhaust turbine for damage, as well.

 

[68442]

The head is fubar also. I just can't imagine how a stray valve lock got in there. I had the springs all off to replaced the valve seals. I checked everything before I put the head back on, there was nothing in the cylinder. I'm going to check my other 2 heads to see if they are all there.

 

[DSM1G90]

Granted, the cause of the problem has been resolved, yet if there was an object in the cylinder, it would also take out the spark plug as well...you think.

For, I had that happen with a simple four cylinder car I had: didn't know that I dropped a small nut down the carburetor and it went into a cylinder. When I started the motor, I heard rattling and suddenly one cylinder went dead. Pulled the plug and the ground electrode was smashed into the electrode. Took out a magnetic probe out of the toolbox, shoved it into the sparkplug hole and extracted this small nut which looked pretty banged up. Put a new sparkplug in and got on my way...

 

[68442]

I put 400 miles on the car, that might have been in there the whole time. It must have been in the intake system because I vacuumed out the pistons etc before I put the head on.

I checked the other heads, all locks are there. Whatever it is wasn't making the rod knock sound, I'll take the motor apart onces its pulled. Oil was clean when I dropped it.

At least I'm getting better at taking it apart

It'll have a wideband, walbro 190, and dsmlink before it starts again. I'm not going to chance running lean again.

Of course nothing could be done about that object, I'll be a lot more careful when putting it together.

 

[68442]

I was removing the intake from the head and heard something in the intake. 2 more chunks came out of the intake, already beat up looking. Turbo fins look fine. I will have to make sure the whole intake system is clear. I'll take the turbo apart also.