What is cylinder liner protrusion on Y485?

[Bob Rooks]

Yes its Coal fire "Super heated" with 3200 PSI at the throttle valves., 750 MegaWatt units.

Curious if that was classed as SC or USC type plant.

 

[Tim Berframe]

Torque is good. Compression is normal. Pressurized water to 20psi. Copious water vapour in #4. Tore apart and pushed out the swirl chamber splice blocks. Inside #4 was oily carbon with no sign of water. #1 was dry light carbon. Cleaned it up and inspected it carefully. There is no crack or flaw in there. So, that seems to rule out a cracked head - there is nowhere for compression to get to water passage other than through the fire rings on gasket. I am back to pointing at the gasket not sealing.

Liner protrusions are 1.5 thou, the deck is dead flat, the head is flat. The 395 book says protrusion should be 2.75 thou to 5.9 thou. All I can try now is shimming the liners up 3 thou if I can find someone to make them.

 

[Tim Berframe]

Thanks. Good to know there is a backstop if it comes to that. I did search high and low on your website.

 

[Tim Berframe]

try a double gasket, see what happens, I don't see complete sealing on the head to gasket interface.. you did tighten the head bolts to the proper sequence, using the proper torque, right?..

Given how this gasket has metal fire rings crushing on liner protrusion, I dont see how two gaskets could work. First I'll try old school copper sealant and pump up the torque a bit. If that dont hold, ill try two. What is to loose?

I did torque correctly, new dry bolts, thread chased holes, measured depth, etc etc etc

 

[Bob Rooks]

Given how this gasket has metal fire rings crushing on liner protrusion, I dont see how two gaskets could work. First I'll try old school copper sealant and pump up the torque a bit. If that dont hold, ill try two. What is to loose?

I did torque correctly, new dry bolts, thread chased holes, measured depth, etc etc etc

I'm not saying don't do it, it's just that you are would have two soft fire rings together. Plus decreased compression, and these are compression-ignition engines.
It always helps the draw-down to torque in steps (maybe you did that). First step is 1/2 the total torque value in sequence, then full torque in sequence.

 

[Tim Berframe]

I did torque in 3 sequences . Roughly 1/3 at a time

 

[Bob Rooks]

Google cylinder liner shims. You will likely have to compare dimensions. Perkins seems likely.

Engine Liner Shims for Sale | Vander Haag's

 

[Bob Rooks]

Liner protrusions are 1.5 thou, the deck is dead flat, the head is flat. The 395 book says protrusion should be 2.75 thou to 5.9 thou. All I can try now is shimming the liners up 3 thou if I can find someone to make them.

What was the thickness of the fire ring, or did you check that?

 

[radios1]

Google cylinder liner shims. You will likely have to compare dimensions. Perkins seems likely.

Engine Liner Shims for Sale | Vander Haag's

that could do it, I didn't see a good seal on the liner to gasket interface, there was a leak there, the liner shims may be just what's needed..

 

[Bob Rooks]

What Is Liner Projection? What Is Liner Protrusion? What Are Counter Bores? - YouTube