Hello all. New Discovery 2004 owner i recently purchased for $3k, Running really rough with multiple misfires. After doing research, I decided to pull the heads and replace the head gaskets, plugs, wires, coils and O2 sensors. After getting the driver side head off I noticed some damage between 7 & 5. Not sure what could have caused this. I am not looking to pull the whole engine block so I am looking for suggestions. I was thinking maybe JB Weld ExtremeHeat?

 

Is that as deep into the deck of the block as it looks?

 

Yeah it's deep. I'll clean it up tomorrow and see if I can measure the depth.

 

I don't think that block can be saved, I hope I am wrong. I have never tried JB Weld vs combustion chamber pressure.

how did the head look?

 

The head looked fine. Here's a closeup of the damage. Almost looks like it was damaged at the factory. Not sure what could have caused this.

 

Head seems ok. Closer examination indicates the #5 sleeve has slipped. I know most folks would say this thing is done and I need to get a new block but I went ahead and filled in the hole with JB Weld. We'll see how long it lasts!

 

Welcome... I'm new too!

I'm thinking I have the same problem on my parts truck. I need to tear the motor apart in the next couple days and see. From the research I have done. That's not repairable.

What likely happened is the there is a crack between the sleeve and water jacket. When that happens steam gets between the sleeve and casting of engine. Which lubricates the sleeve allowing it to go up and down and the steam shoots upwards, eating into the block and head gasket.

To me it looks like the sleeve is shifted downward about 1/16" of an inch compared to the other liners (hard to tell from the photos). If that's the case the block is likely junk or very pricey to fix. You cant just deck the block and put a top hat kit on it without addressing the leaking block. Otherwise the water vapor will end up in the bottom of the engine instead of the top.