honing a motor
AudiWorld Super User
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Can you take a picture of what you're dealing with?
Generally, using a "bottle brush" is easier than an actual hone. I'd like to see how thick the rust in the cylinder is before you start. Are you changing rings or has the engine just sat for awhile and now you're putting it back together. You might be able to get by with WD and steel wool.
New Member
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Re: honing a motor
From a search on the web...
When an engine is rebuilt, the cylinders usually need attention. Wear tends to create taper in the upper part of the cylinder that can reduce ring sealing and increase blowby and oil consumption if not removed. The cylinder may also be out of round, scored or have other damage that requires correcting before a new set of rings will seal properly.
The main objective when refinishing the cylinders is to make the walls as straight as possible (no taper), the bores as round as possible (minimal distortion, which is especially important with today's low tension rings), provide the right amount of crosshatch for good oil retention and ring support, and produce a surface finish that meets the requirements of the rings. This is done by boring and/or honing the cylinders in one or several steps with various types of abrasives (vitrified or diamond).
When an engine is rebuilt, the cylinders usually need attention. Wear tends to create taper in the upper part of the cylinder that can reduce ring sealing and increase blowby and oil consumption if not removed. The cylinder may also be out of round, scored or have other damage that requires correcting before a new set of rings will seal properly.
The main objective when refinishing the cylinders is to make the walls as straight as possible (no taper), the bores as round as possible (minimal distortion, which is especially important with today's low tension rings), provide the right amount of crosshatch for good oil retention and ring support, and produce a surface finish that meets the requirements of the rings. This is done by boring and/or honing the cylinders in one or several steps with various types of abrasives (vitrified or diamond).
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Re: Can you take a picture of what you're dealing with?
the motor has been stitiing apart for a while and is being put back together. no i am not changing the rings. but it seems like i have this much work out for me i might as well. i will take a pic of it and email it to you i dont know who to post pics on the fourm. so gimme you email address. thx again, anthony
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Re: Can you take a picture of what you're dealing with?
Not changing the rings after a hone? Won't get good compression readings as the old rings are worn down to the size of the old bore. Old bore and rings will be slightly smaller than the honed bore. You really really need to get new rings...
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Yes.
If it's really light rust you can probably get by with a Bottle Brush and new rings, rather than using a regular hone or sending it into a machine shop to be put on a Sunn machine or equivalent. Get a pic for us so we can see how bad it is - get a close-up of the cylinder wall, or take the block to a good machine shop and let them be the judge.
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