What Is Engine Block Reboring And Sleeving

Posted in Crank, Oil and Piston | Asked on May 15, 2010

I need to know what the processes actually are and can jus one cylinder be rebored

There are 4 Answers for "What Is Engine Block Reboring And Sleeving"

  1. Pierre B says:

    No all of it has to be redone
    When they rebore your block the pistons over time make grooves in the block from going in the same possition all the time and the port where your piston fits in is called the sleeve

    When you replace pistons the put new sleeves in for the new pistons so everything runs smooth

    When they rebore they make it or take out the rough parts from when the old sleeve was there in place so its bassically filling it down so everything has a smooth finnish and there is no rough parts to it

    And like i said you cant do just one either if its a 4 cylender or 6 and such if you do one you have to do them all because its not logical just to do one

    Hope this comes on handy or you can try to google it aswell

  2. Brad G says:

    You can ‘sleeve one cylinder’ but you must sleeve it to the same size as the other cylinders are bored to!! Boring means to enlarge the cylinders (where the pistons go) to a larger size. Sleeving is done by overboring the cylinder to its maximum size and then istalling a steel ‘sleeve’ to bring it down in size to stock. After you sleeve then you bore again to size the new sleeve to the rest of the motor. All the pistons need to be the same size to keep the compression ratio the same on all cylinders. If one cylinder has higher compression than the others, the engine wont idle smoothly, and at high rpms it wont be balanced properly so it will ruin the bearings in a much shorter time>

  3. worko says:

    unlike the first answer yes you can just have one cylinder sleeve replaced but he is right that u may aswell do them all while you are there.
    engine block reboring is your engine block is machined to a bigger size cylinder.it smooths out the bores and makes them like new.boring a block can only go to a certain size. the bore thickness (wall of the cylinder) needs to be wide enough to accomodate the stresses that an engine produces otherwise it will crack split or do other nasty things.
    sleeving is literally a sleeve slid into your engine block that makes the bore for the piston to travel in and do its thing lol
    hope this helps

  4. Gordon L says:

    An engine cylinder is bored out when it is worn too much that the rings wont seal, or if debris had damaged it, or it is out of round, and has too much taper, meaning the cylinder is not the same exact diameter top to bottom. Some taper is needed, but too much causes problems, like lost compression, or blue smoke from loss of oil control. Once the cylinder is bored, it then needs to be honed, to get a microscopic crosshatch pattern for ring sealing. Typically if one cylinder needs to be bored, then that means new piston, and you dont use a single odd size piston in an engine, all of the cylinders must be the same size. There are standard overbore sizes for an engine such as .030 overbore, called 30 over. you would bore the cylinders say 30 over, and install a set of 30 over pistons. An iron cylinder sleeve is used on an aluminum engine, because the alloy cant take the heat and pressure of combustion, and friction. These are a replaceable part in most engines, but some of the newer lightweight blocks have them cast in when the block is made, and cant be easily replaced. A sleeve can also be used on an iron block, if one cylinder has been too damaged for boring out. This of course requires an experienced machine shop that knows how to do it. Normally though this is only done when the block is rare enough to warrant the machine shop costs. So basically boring a cylinder is the process of making it larger and revealing a new surface for the piston rings to ride on. Sleeving is the process of actually replacing the cylinder with a new one. If an engine has one bad cylinder, and the rest are good, then a sleeve can be installed in the bad one, and the size can be matched to the others so they are all the same size. Hope this helps some

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