ls1nova

So what's the story here? I've read that GM states not to hone the cylinders when replacing the rings. Is this a common practice?? I have never heard of anyone not honing when re-ringing a motor.

The reason I ask is I'm currently refreshing the bottom end in my 502 mag. It has the metric low tension rings. My plans are to deglaze the cylinders, replace the rings, polish the crank, and replace the bearings. So should I bother deglazing with these low tension rings??

Thanks for the input,
Frank

H2Xmark

I would measure the cylinders for out of round and if they dont have any taper in them then I would call the piston ring company and see what they say about honing,

TylerCrockett

iTrader: (1)

I would hone the cylinders especially if it ran synthetic oil before.

Nova 26

I worked as a line mechanic for 10 years at a Honda auto dealership about 15 years ago.The dealerships rarely rebuild engines or transmissions today, they just replace with a factory rebuilt unit,but back then, we rebuilt engines all the time. We used to get bulletins from Honda with service tips and recommendations, one of these bulletins said Do Not hone Honda engines when rebuilding them.I asked the shop foreman about it and he said you have to hone to "break the glaze" that builds up on the cylinders or the rings won't seat. So I called Honda tech line, and talked to an engineer with Honda R and D and he told me that they sent that bulletin out because honing was unneccesary. With chrome moly rings, they are hard enough that they cut through the glaze almost instantly at start up. He also mentioned that techs were not cleaning blocks properly after honing, leaving some grit in the bores causing a lot of unnecessary damage. I have to say that I rebuilt dozens of engines, never honed, and none smoked or had problems from not honing. As mentioned above, checking for bore trueness is critical. We rebuilt some high mileage engines, over 200,000 miles, and I never saw a ridge in the top of the bore in a Honda engine either.I asked how this was possible and the engineer said that Honda chemically treats the blocks so the bores are very hard. You could always see the original cross hatch even in those 200,000 mile engines.
So does this mean I say don't hone your block? Only if you run Honda engines in your boat.Tyler Crocket has built many marine engines and if I was building an engine for my boat, I would listen to the voice of experience.

Tim@DOA

No disrespect, BUT, there is no such thing as "chrome moly" rings. You have either Chrome, or moly impregnated. Honing creates a proper cylinder wall facing for the type of ring set being used.