Bob Rooks
Elite Member
Curious if that was classed as SC or USC type plant.
What is cylinder liner protrusion on Y485?
- Thread starter Tim Berframe
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OP
Tim Berframe
Bronze Member
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.
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.
OP
Tim Berframe
Bronze Member
Thanks. Good to know there is a backstop if it comes to that. I did search high and low on your website.
OP
Tim Berframe
Bronze Member
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
Elite Member
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.
OP
Tim Berframe
Bronze Member
I did torque in 3 sequences . Roughly 1/3 at a time
Bob Rooks
Elite Member
Google cylinder liner shims. You will likely have to compare dimensions. Perkins seems likely.
Engine Liner Shims for Sale | Vander Haag's
Engine Liner Shims for Sale | Vander Haag's
Bob Rooks
Elite Member
What was the thickness of the fire ring, or did you check that?
radios1
Elite Member
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
Elite Member
OP
Tim Berframe
Bronze Member
These are the protrusion measurements. I didnt bolt them down - just tapped them down to make sure seated fully. Used a dial indicator and measured each place several times. My dial is 100 thou range so not ideal - .5 thou is best I can read off it. Nothing alarming here though. I would think a gasket could make up 1.5 thou difference?
radios1
Elite Member
you have 3 thousands on #4, though.. how thick is the gasket?.. also, the cylinder liners are NOT even!.. they should all read the same..
Bob Rooks
Elite Member
Still waiting to hear the thickness of the fire ring. To me #4 looks bad. Don't think shims are going to help that. I think you will have to have the block decked. Please review that video I posted.
OP
Tim Berframe
Bronze Member
Yes, I watched that video and dozens more of that guy痴 over a year ago when contemplating the rebuild. This machine has been broken for almost three years now. I fully understand the concept. I have read different tolerances for other engines but have seen none for Yangdong. For example, there is a marine Perkins similar size that says individual liner must be within 1 thou, no two cylinders can稚 be more that 2 thou different and a range of 7 thou. In that example, the head gasket is very forgiving. Others are much more specific and tighter tolerance.
The deck is dead flat. The counter bores will have to be machined and then liners shimmed to get all these measuring the same. Every time I learn something about this machine it makes me sad. Lol
The fire rings are about 60 thou IT did crush all the way around but clearly not uniformly
OP
Tim Berframe
Bronze Member
Well, it has been 4 years since the last post. The machine sat in my yard split apart all this time. The block was sitting at the engine rebuilders for over a year.
I can report that I spent the past two weeks putting it together and it lives.
After the last post, I rigged something to press down on the liners uniformly and bought a better dial gauge. The protrusion measures showed the problem. The cylinder bores were not perpendicular to the deck. All of the liners were tipped so the front edge was higher than the back by 1.5 thou. Protrusion was lower than spec on 1,2,4. 3 was higher than the rest because the counter bore was wrong.
We cut the counter bores to a uniform depth perpendicular to the cylinder bores. Then shaved the deck perpendicular to the bores so that it produced 5 thou protrusion on all liners.
I changed the fuel bowl and fuel line. I had to source and install new copper crush washers under the injectors as they were leaking combustion gasses. I changed dozens of o rings and banjo fitting washers. I disassembled the fuel injection pump to try to fix the internal leaking. Replaced a couple hydraulic lines. Replaced a couple chinese hydraulic fittings and removed and reassembled every hydraulic fitting connection. For the first time ever, I have no wet hydraulic connections. I spent an entire day disassembling and repairing the entire wire harness. It has deteriorated a lot. I repaired at least 25 connections. I also discovered several differences between the wiring diagram and my machine. Anyways, I now have all gauges working except for the battery warning light. It is on all the time. I took apart the brake system and reassembled. I had to remove the brake pedal shaft assembly to free it up. It all works now but the braking power is still too low in my opinion.
It started easy and ran with no smoke. It gave me a scare when the temp guage pinned as soon as the thermostat opened. My laser thermometer showed 90C on the head and 80C at the thermostat. I put in a mechanical temp gauge and it runs cool even in this heat wave.
I ran the back hoe for an hour yesterday and nothing broke and temp didn't go above 180F and oil pressure was good. It runs smooth and steady. I have never once even when brand new been able to start it without glow plugs. Not one of the glow plugs on it works now (ordered but not arrived yet) and it starts easy.
I have a large oil leak at the front cover to resolve and then hopefully, after 7 years, I can do some work with this thing.
I can report that I spent the past two weeks putting it together and it lives.
After the last post, I rigged something to press down on the liners uniformly and bought a better dial gauge. The protrusion measures showed the problem. The cylinder bores were not perpendicular to the deck. All of the liners were tipped so the front edge was higher than the back by 1.5 thou. Protrusion was lower than spec on 1,2,4. 3 was higher than the rest because the counter bore was wrong.
We cut the counter bores to a uniform depth perpendicular to the cylinder bores. Then shaved the deck perpendicular to the bores so that it produced 5 thou protrusion on all liners.
I changed the fuel bowl and fuel line. I had to source and install new copper crush washers under the injectors as they were leaking combustion gasses. I changed dozens of o rings and banjo fitting washers. I disassembled the fuel injection pump to try to fix the internal leaking. Replaced a couple hydraulic lines. Replaced a couple chinese hydraulic fittings and removed and reassembled every hydraulic fitting connection. For the first time ever, I have no wet hydraulic connections. I spent an entire day disassembling and repairing the entire wire harness. It has deteriorated a lot. I repaired at least 25 connections. I also discovered several differences between the wiring diagram and my machine. Anyways, I now have all gauges working except for the battery warning light. It is on all the time. I took apart the brake system and reassembled. I had to remove the brake pedal shaft assembly to free it up. It all works now but the braking power is still too low in my opinion.
It started easy and ran with no smoke. It gave me a scare when the temp guage pinned as soon as the thermostat opened. My laser thermometer showed 90C on the head and 80C at the thermostat. I put in a mechanical temp gauge and it runs cool even in this heat wave.
I ran the back hoe for an hour yesterday and nothing broke and temp didn't go above 180F and oil pressure was good. It runs smooth and steady. I have never once even when brand new been able to start it without glow plugs. Not one of the glow plugs on it works now (ordered but not arrived yet) and it starts easy.
I have a large oil leak at the front cover to resolve and then hopefully, after 7 years, I can do some work with this thing.
