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MG MGB GT V8 Factory Originals Technical - Cylinder Honing, DIY job?

hi guys. i've just finished stripping my 3.5 sd1 v8 engine down and its ready to be measured, honed and reground where necessary. i just wanted to know, is it possible to hone the cylinders yourself or is it a job best left to the pros? there are various honing kits available but just wanted to know if its better getting it done professionally.

cheers, joe

p.s., ive suddenly felt the urge to carry out as much work as i possibly can now after recieving a quote for some body work. how does £1200 (labour only) per side, to replace the sills. i had to provide the parts myself. im not going to name the workshop but they specialise in classic cars and i thought to be a very good place to get the work done, how wrong i was.
J P Connor

Have a shop do it with a ball aka dingleberry hone of the proper grit to match your rings. I just priced this locally and they want $40 for honing a V8. Just glazebreaking, but best left to someone with experience. Probably cheaper than buying the hone and doing it yourself.

I've read bad things about the hones that use stones.
Glenn

you CAN get away with a QUICK ballhose, just to scuff the Cylinders up, but you really should have a shop do it to make sure the cross-hatch is set properly. if it needs more than a quick scuff than it is definitely work having a shop due it to make sure you don't end up with a taper in the bore.

NEVER use a stone type hone like used for brake calipers, they are not really designed to be used off the sunnen machine and can really wreck things in a hurry.
Larry Embrey

JP, in your best interest this job should be done on a Sunnen Precision Honing machine or similar machine. Due to upper cylinder wear from piston thrust the cylinders will likely to be worn slightly egg shaped or have a worn area in the bore at the top ring area. A flexible hone will only rough up the surface but does nothing for alignment honing. At the bottom of the cylinder the same egg shape wear might have happened to the cylinder on the opposite side as the top of the cylinder because of scuffing of the piston skirt. Again a flexible hone would not be a good choice. The flexible hones are usually used after an rough alignment bore has been done and a proper grit has been chosen just for the type of material used in the new rings.
Dann BCC
Dann Wade

Some things are best left to the experienced and honing is probably one of them.All good points have been made already,I would add that honing with a steady oil supply is desireable.Most shops have some sort of wet honing machine,if not a Sunnen.Even the cheaper ones still use a head that takes Sunnen stones.As mentioned,taper and out of round would not be detected with a ball type hone so this is really the best way to go.A rigid hone will pick up an out of round situation that a bore gauge might not.Just as important as a good hone job is break-in.Light oil on the cylinder walls on assembly,an initial 15-20 minute fast idle for cam break-in,then driven with a load immediately for ring break-in.Idling is to be avoided at all costs.
Dale

thanks guys, sounds like it isnt a DIY job after all! i have been quoted £80 for a light hone for my block and the guy in the shop said it was a "quick dip in each bore to get the glaze off" doesnt sound like he's a pro. i'll hunt around and see if i can find anyone with the professional equipment and they know what they're doing. thanks for the advice.
J P Connor

I'll add that I re-ringed (re-rang, re-rung?) a Chevy 350 a long time ago - did it myself with a Lisle stone hone (didn't know any better) and it ran fine for 60 or 70,000 miles. The block had 77,000 on it before the rebuild. Put it in another car and it's still running - a temporary motor so I can move the car around untill it's replaced.

Another point - many machinists don't recommend using a ridge reamer to help with piston removal. Those things can do a lot of damage.
Glenn

JP,

If you can't find one on your side of the river then try Burton Engineering at Ilford or I can recommend Elmsleigh Engineering at Benfleet in Essex - they do all my machine work.
Chris at Octarine Services

This thread was discussed between 20/08/2004 and 26/08/2004

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