Discussion
I think you've completely misunderstood what 227's has meant. I don't for one minute think he's suggesting you hone a bore out .010" to the next oversize. To me it's obvious what he means.
As an aside some engines only have the capacity to oversize the bores to .005" maximum. So, I would imagine that you'd need to find a slightly oversized/graded piston and hone until you get the correct clearance, ie no boring involved.
As an aside some engines only have the capacity to oversize the bores to .005" maximum. So, I would imagine that you'd need to find a slightly oversized/graded piston and hone until you get the correct clearance, ie no boring involved.
HustleRussell said:
Nope
But clued up enough to run a mile if an engine builder told me he was going to ‘get bigger pistons an hone until they fit’
You quite clearly have no idea whatsoever and really shouldn't be taking part in this thread, it's no surprise the OP is confused. Machine shops DO hone blocks to the next piston size up, how on earth do you think they can bore and hone +.2 total diameter?But clued up enough to run a mile if an engine builder told me he was going to ‘get bigger pistons an hone until they fit’
You've never built a bottom end yet preach to the World about how to do it?
This is all getting very silly. The Toyota advice to hone no more than 0.8 thou on diameter is the most bizarre workshop manual advice I've ever seen and contrary to all normal machining practice. The most comprehensive discussion I can recall on honing a few years ago with recommendations on bore finish and honing material allowance was here.
http://www.pistonheads.com/gassing/topic.asp?t=835...
Further links to proper honing practice and suggested material removal allowance here.
http://www.autospeed.com/cms/article.html?&A=1...
I doubt if anything in the current thread can't be answered by a good read of those above.
http://www.pistonheads.com/gassing/topic.asp?t=835...
Further links to proper honing practice and suggested material removal allowance here.
http://www.autospeed.com/cms/article.html?&A=1...
I doubt if anything in the current thread can't be answered by a good read of those above.
HRCM said:
The manual says my bores are 73.400+/-.005 mm. Can anyone advise what is the most I could hone out before needing a rebore? Apologies if it's a stupid question (i.e. Top limit).
Hmmmm. I've never seen a bore size tolerance that was as specified as +/- the same number. It's always x.xx mm -0.00 mm/+y.yy mm.In other words there's a minimum size which is the actual target and then a maximum allowed over that. However your question is not for an OE tolerance. It's what can you get away with. Rusted piston rings usually cause damage about 1 thou deep so 2 thou on diameter to hone it out. If your bores clean up at + 2 thou over the max std spec and you use new rings it won't be the worst thing in the world. Much more than that and you'll be looking at a rebore though.
Mignon said:
This is all getting very silly. The Toyota advice to hone no more than 0.8 thou on diameter is the most bizarre workshop manual advice I've ever seen and contrary to all normal machining practice. The most comprehensive discussion I can recall on honing a few years ago with recommendations on bore finish and honing material allowance was here.
http://www.pistonheads.com/gassing/topic.asp?t=835...
Further links to proper honing practice and suggested material removal allowance here.
http://www.autospeed.com/cms/article.html?&A=1...
I doubt if anything in the current thread can't be answered by a good read of those above.
I think with a lot of those Japanese manuals they dont translate to well we use to get strange quoted figures within factory Honda repair manuals normally electrical values or component test inaccuracy's etc sometimes mechanical too like piston ring placement where the top ring and 2nd ring were back to front http://www.pistonheads.com/gassing/topic.asp?t=835...
Further links to proper honing practice and suggested material removal allowance here.
http://www.autospeed.com/cms/article.html?&A=1...
I doubt if anything in the current thread can't be answered by a good read of those above.
that was one I clearly remember probably no big deal back then we was one of the few dealers who built engines rather than the usual factory short block method etc Dear all,
As promised, I'm posting back now I have more to add. Yes, it has taken me that long. I've been busy with other things as well as this and I always take my time anyway.
I'm happy to say the engine is now back together, back in and running sweetly.
The bores were much better condition than the pictures might have you believe and cleaned up nicely after a very light hone at a machine shop.
I did measure up the cylinders after cleaning up the block and they were within the limits Mignon states above.
The +/- tolerance point you commented on Mignon was my brain fade and not the manufacturer's recommendation.
As promised, I'm posting back now I have more to add. Yes, it has taken me that long. I've been busy with other things as well as this and I always take my time anyway.
I'm happy to say the engine is now back together, back in and running sweetly.
The bores were much better condition than the pictures might have you believe and cleaned up nicely after a very light hone at a machine shop.
I did measure up the cylinders after cleaning up the block and they were within the limits Mignon states above.
The +/- tolerance point you commented on Mignon was my brain fade and not the manufacturer's recommendation.
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