Repairing one cylinder?

[garrettohio]

Can you just repair one cylinder if the other two is 400 and 430 psi.the number one cylinder was like 230 then went 330 after adding oil.i ran the motor with valve cover off and valve train looked to be working ok.its weird because there is no blowbye but cylinder is dead smoking raw fuel.can I hone and rering one cylinder.

 

[loggin]

Can you just repair one cylinder if the other two is 400 and 430 psi.the number one cylinder was like 230 then went 330 after adding oil.i ran the motor with valve cover off and valve train looked to be working ok.its weird because there is no blowbye but cylinder is dead smoking raw fuel.can I hone and rering one cylinder.

You can just repair one cylinder, but it is generally advisable to do the rest while you are in there since there is a fair bit of labor involved in accessing the internals of the engine.

Up to you..

 

[North Idaho Wolfman]

Yes, if there is not such damage that it requires resleeving the cylinder.
Your issue is most likely a broken piston /rings / bent connecting rod.
You can only guess till you open it up.

 

[fried1765]

There is a long history of replacing individual aircraft engine cylinders.

 

[garrettohio]

Yes, if there is not such damage that it requires resleeving the cylinder.
Your issue is most likely a broken piston /rings / bent connecting rod.
You can only guess till you open it up.

The factory Kubota list several different part numbers for pistons.how do I know which piston mine has if I need one?

 

[North Idaho Wolfman]

The factory Kubota list several different part numbers for pistons.how do I know which piston mine has if I need one?

Need the Engine and tractor serial numbers to tell what parts you need.

 

[StephenR]

Could there be a chance that you might have a bad injector that is dumping too much fuel into the cylinder and washing the rings out?

I realize that could be a long shot, but it might be worth moving the injectors around to check it out.

Good luck.

 

[garrettohio]

Could there be a chance that you might have a bad injector that is dumping too much fuel into the cylinder and washing the rings out?

I realize that could be a long shot, but it might be worth moving the injectors around to check it out.

Good luck.

I moved the injectors around.but still number one cylinder isn't firing.

 

[lmichael]

If you're going to go through all the work to tear it down, you've done 90% of it. Why stop there? Do the whole job, do it right and once and you're done

 

[lugbolt]

measure how far down the cylinder all 3 pistons are, when they are at TDC. Obviously one at a time, and record them. Remember, these things are precision machinery so a tape measure isn't accurate enough. A dial or digital caliper can work. Or better yet a depth micrometer. There is a specification for this in the shop manual.

Once that's done, if all 3 are the same or close to the same (close being like .010") then you can proceed to removing the pistons from the cylinders. If one is a lot lower than the other two, that one probably has a bent rod which wouldn't surprise me.

also if it's got 230 psi, it doesn't matter how much fuel it is or isn't getting, it's not gonna run on that cylinder. 230 psi doesn't make enough heat to ignite the fuel. Diesel doesn't really wash a cylinder down like gasoline does. Overfueling generally burns pistons and/or bends rods. Oil in a cylinder during a compression test can do the same thing. If it's low dry, it's low and at that point one of two things needs to happen. Leakdown test and/or teardown.

repairing one cylinder? It can be done so long as the cylinder isn't tapered or oblong'd or cracked or scarred up.

 

[GeoHorn]

There is a long history of replacing individual aircraft engine cylinders.

True… done many of them myself…. but for the benefit of those not familiar…. Aircraft engines typically are designed with separate heads/valve-assemblies instead of “shared” heads/assys…. (in fact, the entire cyl assy is separate from adjacent cyls)….which means that individual cyls and pistons, etc can be serviced without disturbing adjacent ones.

In a typcial mono-bloc engine such as most tractors, vehicles, stationary-engines…the head/valve-assy’s service more than one cylinder and require greater disassembly. If all that disassembly-work is done…would be a good opportunity to renew parts in adjacent cyls. (which is what loggin was implying, I believe.)

This is similar to a clutch-job… If I had to split my tractor to replace a clutch-disc… I”d darn sure replace the pressure-plate, throw-out bearing and pilot bearings while I’m in there… maybe trans oil seal also, etc etc.