Dry liner removal and installation in a Z750 eng L175????????

[aquaforce]

Ok, need info.

I need to get the liners out of my engine. These are dry liners in this Z750 two cyl. I started out burning four weld lines down the length of the liner trying to shrink it and then just bump it out no luck.
Now I'm affraid that I might have burned through one of the liners in one spot not good.


What advice does anyone have for this task?
Machine shop is out of the question. He says that cutting them out is the way he would go at over $120 per hole I can do that my self for free.

How would you install the new ones? Is there a sealant or something that goes between the block and liner. My shop manual has no info on this

 

[aquaforce]

So............ nobody here has done this I guess.

Today is engine day so I am going to be working at it all day long.

 

[cmh]

Sorry to hear about your liner troubles, First of all they should be pulled out with a tool to do so. The old hillbilly way of arking a liner ( running a cold
bead up the liner wall) usually works, But it should be a cold stringer not hot
like you are welding. This is where problems come in. The block may becomb distorted, (oout of round) resulting in a hard time instaling the new linner, as well as making the linner out of round. A linner a little out of round will wear very quickly, while very much out it will seize up as it comes up to working temp's.

 

[aquaforce]

Sorry to hear about your liner troubles, First of all they should be pulled out with a tool to do so. The old hillbilly way of arking a liner ( running a cold
bead up the liner wall) usually works, But it should be a cold stringer not hot
like you are welding. This is where problems come in. The block may becomb distorted, (oout of round) resulting in a hard time instaling the new linner, as well as making the linner out of round. A linner a little out of round will wear very quickly, while very much out it will seize up as it comes up to working temp's.

Since I'm in the south I guess it would be the red-neck way

Now I'm using a hack saw blade to cut the liner loose. Out of round could be the least of my worries. Water ran out of the bottom of both liners so the parent bore must be cracked.
I'll know pretty soon as this process is slow.

 

[cmh]

Hey no serious heritage damage intended, hillbilly / redneck / backyark engineer ! all the same; Just a bunch of guy's fixin' stuff with a beer close by !

Here is a link to a site that has a block & other stuff for the Z751 for sale if you need it, I got it from someone on this site ? do not remember who ! good luck.
.
http://www.wengers.com/parts/Farm-Tractor-Parts/Kubota/L185/L185/Engine-Diesel/

 

[aquaforce]

Hey no serious heritage damage intended, hillbilly / redneck / backyark engineer ! all the same; Just a bunch of guy's fixin' stuff with a beer close by !
QUOTE]

I have a sense of humor and like to laugh so I was just trying to be funny too.


That link is not working but I see the address so I can search it.
Thanks

 

[aquaforce]

Yes they sure do have my block.

http://www.wengers.com/

There is hope for my tractor now.



Thanks

 

[aquaforce]

I am happy to announce that my fears of burning through the liner with the welder are false.
And my interpretation of coolant leaking behind the liners is wrong.

It is about time I had some good luck

I got the liners out using a sawzall blade. Cut through the liner until it was very thin, then lift an edge beside the cut with a chisel and insert a flat screwdriver and POP, the liner rolled inside and I lifted it out.

My block is in great shape and there are no cracks so now I am ready to start pressing these new liners back in.
I will post some pics in the press.

Now I have to go lower my press bed.

 

[Ob1kubota]

All I can say is you are one tuff dude to take a pair of Vise Grips an a sawzall blade and cut through parent bore cylinder liners.....glade the block is solid. I'm too lazy for this I take it to a machine shop in Birmingham. Looks like you are on your way back now aqua...

 

[aquaforce]

I'm too lazy for this I take it to a machine shop in Birmingham. QUOTE]


I'm to lazy for this too but I am determined to stay on budget this year to finish another project. If I took this to the machine shop my boat would have to wait another year, I can't have that.


These liners are pretty thin and once the surface glaze is broke the cut is just a "steady as she goes" job. I used a brand new blade designed for hard metal so these sharp teeth really helped a lot!

 

[eserv]

The liners are fairly easy to remove on a kubota engine any machine shop would be able to make you a plate. Have you installed the new ones yet........ If kubota sleeves they will need to be bored to size.......guess you could do it with a ridged hone but I think you better go to that machine shop yet!!!!
Ed service

 

[aquaforce]

Don't have the new ones in yet. Had a lot of other things to tend to this week. I should get them in this weekend.

I was looking at the pistons and the liners just out of the box and the piston will not even get close to fitting in the liner. That tells me that it will have to be cut but I will find a shop that is reasonable. $120 per hole is just outrageous. I can have a bbc punched out for less than that and it has 8 holes.

 

[aquaforce]

Well I stiffened up my press bed by using a forklift upright that I cut off. That went under the block. Then I used another forklift piece on top of the liner and started the work.

 

[aquaforce]

My little air compressor can't keep up with my press pump so after getting this far I had to wait for the compressor to catch up.

 

[aquaforce]

I prepped the block by using a dingel hone lightly only to knock off the black build-up that forms between the liner and the block. Then cleaned the bore out with brake clean making sure it was scrubbed well. Next WD-40 coated the bore and liner very liberally.
The liners pressed in very smoothly and I am very happy.


Now the shop that will dyno my 496 will cut the sleeves to fit the pistons and I am ready to load.

 

[aquaforce]

Got the block back from the machine shop today. $180 to bore/hone and skim the deck to true it up. They took .005 off the deck to get it all cleaned up so now I am going to need to clearance the pistons when I get them loaded. The old pistons had an impression of the pre-chamber in the top of them so I wonder about the .008 shims for the head gasket.


I got the head all build back. Lapped in all the valves, put in the injectors and the intake. There are a few more studs to get moved over from the old head but it looks great with all new parts.

More pics coming.

 

[Ob1kubota]

Aqua I don't know if you want to try this or not but I've put modeling clay on top of my piston reliefs before and figured an overrev stress factor of .005 for clearance when I decked my blocks. I adjust the rocker arms to zero and turn her over with every thing torqued down, with the exact head gasket installed then unbolt and measure the thickness of the clay for an idea of valve to piston clearance before putting the fuel to her..... just a thought ...

 

[aquaforce]

Aqua I don't know if you want to try this or not but I've put modeling clay on top of my piston reliefs before and figured an overrev stress factor of .005 for clearance when I decked my blocks. I adjust the rocker arms to zero and turn her over with every thing torqued down, with the exact head gasket installed then unbolt and measure the thickness of the clay for an idea of valve to piston clearance before putting the fuel to her..... just a thought ...

The clay process is one way to clearance them. On this Z750 block the flat top piston rises above the deck very close to .040 or more. I will measure the exact rise after getting the block together.
I didn't know Kubota put that much squeeze to the head. I can see why since the pre-chamber is so large. To get 21:1 compression ratio there can't be any room above this piston.
My Kubota head gasket is .145 and the gasket that came with my head is .185. Since the head is flat and the piston is flat I can do some easy math and find my clearance.
I was reading in my shop manual that Kubota has head shims in .008 increments so that is a good way to make a move without loosing a ton of compression.

 

[aquaforce]

Well the head is completed now. Looks great. I left the neck cover off the front of the head for now because I am checking into having a bung tiged on so I can run a sensor and guage in this engine. There is no way I will operate this thing again if I don't know the engine temp.



Block is bored/honed and decked and looks great. Tomorrow it will get a thourough cleaning for the reload process.


Any other ideas on where I should put the temp sensor???

 

[Ob1kubota]

Man they really decked the block and the heads look good too, this should be a tight rebuild Aqua. Did you resize the rods?