Cylinder Liners

[mwood1129]

I am getting ready to rebuild my z750a. I will be installing new cylinder liners. My question. How much material is safe to remove from the liner with a hone? I will need to remove approximately 0.040 “ to fit the new piston. Machine shop rates are crazy high. Just a thought that a hone would do the job.

 

[mcfarmall]

That's a lot of honing!

 

[Pau7220]

Just a thought that a hone would do the job.

Unlikely you’ll be able to remove that much material. Then there’s the issue of making it perfectly cylindrical the way a boring bar would. You need a good seal on the rings to get the compression ratio where you need it to be. If it goes into egg shape or taper you won’t know it until it’s too late. Hones are meant for a final finish, not heavy material removal.

 

[Motion]

Why would new cylinder liners need to be .040 over? Most liner kits come with the correct piston. I think .040 is a lot to take off any cylinder.

 

[lugbolt]

You will be honing for weeks on end if you work 8 hours a day trying to get .040" out of the liners. And that's with a real hone, with 80 grit stones.

kind like honing a knife. If it's somewhat sharp already, a simple hone will renew the edge. But if it's out of whack, you can hone for days and finally get it back to shape, or you can get a real sharpener and re-grind the edge in a matter of 5 minutes, hone, and then you're razor sharp again. Same deal. To get .040 out of a liner, you will need to bore the liner with a boring machine; bore to within .001" and hone to final size and remember temperature will affect your bore size--if you hone, and the liner/block are hot, when it cools back to ambient it'll shrink the bore dia a little.

 

[Yooper]

I once honed .008” on a single cylinder by hand using an 80 grit hone chucked up in a hand drill. Glad it was only one. Pay the price and have it done right. You’re this far along right? If you do it yourself, make sure you check the bore for taper with a dial bore gauge. Easy to hone a bell shape or hourglass shape when doing it by hand

 

[TheOldHokie]

I am getting ready to rebuild my z750a. I will be installing new cylinder liners. My question. How much material is safe to remove from the liner with a hone? I will need to remove approximately 0.040 “ to fit the new piston. Machine shop rates are crazy high. Just a thought that a hone would do the job.

That's a 2 cylinder with 76mm x 83mm bore and stroke? To me crazy expensive for a scant .040 overbore on a little engine like that would be $100. I would think you could get it done for less.

Dan

 

[GreensvilleJay]

I'm with Motion on this...
Was this not a 'kit' ( sleeve,pistion, rings ) ??

if not, get another piston and rings or maybe it's the wrong sleeve ?

something is drastically WRONG for sure !

 

[Pau7220]

something is drastically WRONG for sure !

Nope… That’s the way Kubota does it. Bore to size after press fit (which can actually distort the liner).

 

[Pau7220]

That's a 2 cylinder with 76mm x 83mm bore and stroke? To me crazy expensive for a scant .040 overbore on a little engine like that would be $100. I would think you could get it done for less.

Dan

The machine shop I use here in Scranton had to raise it‘s rates to $120 /hr. It would probably take the better part of an hour just to set it up. Ya’ll need to re-do your math.

 

[Dieseldonato]

Lisle makes a nice hone set up. Many different grits to choose from for roughing to final finish. A bore gauge is a necessity imo. As well as a way to set it up. Doesn't really take long to do 2 cylinders that small. It is kinda expensive to only use once though.
Lisle 15000 Engine Cylinder Hone https://www.amazon.com/dp/B000GKIE4S/ref=cm_sw_r_awdo_JA3156Z208CPQ81Z0F10

Expect to kill a set of 80 grit stone per cylinder. Set up something to flow honing oil while you hone. They can be ran dry but they heat up like crazy. You'll need a pretty stout and slow drill. Stop frequently to check out of round and taper. If an area starts to taper you'll need to dwell in that area for a few extra strokes. Actually this hone is pretty accurate with the mic gauge built in, at least mine is good enough to get it to with in .005" . Then switch to the finer stones. It's not a sunnen but it's pretty good for home and small shop use.

 

[TheOldHokie]

The machine shop I use here in Scranton had to raise it‘s rates to $120 /hr. It would probably take the better part of an hour just to set it up. Ya’ll need to re-do your math.

If you happened to find yourself in the Baltimore area and its cleaned and ready for the table I would do it while you wait and it would not be a C note.

Dan

 

[GreensvilleJay]

crazy....guess they don't want 'farmers' fixing their tractors on the farms........"
As bad as JD in that respect...
Never head of any other doing that.

 

[TheOldHokie]

crazy....guess they don't want 'farmers' fixing their tractors on the farms........"
As bad as JD in that respect...
Never head of any other doing that.

Its standard practice in automotive machine shops. They often buy generic sleeves which are then cut to length and bored to size after installation. Melling has a catalog filled with them.

Dan

 

[Pau7220]

If you happened to find yourself in the Baltimore area and its cleaned and ready for the table I would do it while you wait and it would not be a C note.

Dan

Hoping to not need your services, but if I do you never know what or who may show up on your door step.
P.S., my son drives frozen from PA for one of your largest grocery store chains in MD…. May require thawing when it arrives

 

[North Idaho Wolfman]

I'm with Motion on this...
Was this not a 'kit' ( sleeve,pistion, rings ) ??

if not, get another piston and rings or maybe it's the wrong sleeve ?

something is drastically WRONG for sure !

Kubota sleeve are ALWAYs Over sized on the inside and require to be bored to fit.

 

[mwood1129]

Where I reside there is only one machine shop within 200 miles. They want $800 to install and fit the sleeves . And the I would need to strip block bare. I think I’ll give the honing a shot. What could go wrong right ??

 

[TheOldHokie]

Where I reside there is only one machine shop within 200 miles. They want $800 to install and fit the sleeves . And the I would need to strip block bare. I think I’ll give the honing a shot. What could go wrong right ??

A lot can go wrong.

Dan

 

[North Idaho Wolfman]

Where I reside there is only one machine shop within 200 miles. They want $800 to install and fit the sleeves . And the I would need to strip block bare. I think I’ll give the honing a shot. What could go wrong right ??

Your wasting time and money.
I've got a really high dollar hone and It just doesn't work!

 

[GreensvilleJay]

Generally speaking tractors, gas and diesel are. All the 'kits' for gas tractors are 'matched sets'...NO machining is required. I know the sets for my Buda Diesel are easily 'user installed'.
It sure sounds like that machine shop with an $800 quote is gouging the customer. Ain't no way it'd take 8 full hours to install one sleeve