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1978 Piston clearance for STD Bore or .030 Boar

Crap, Sorry, Evinrude 1978 15hp 15804B 2 stroke 2 Cylinder.
I have a new .030 piston set , original OEM parts from 1981 I just received, need to give the info to the guy doing the work, we assumed it's in a manual somewhere, still looking, I was going to bring him the original pistons to get an idea of the current clearance.
 
Doesn't matter if STD or .064 oversize, prime is .003-.005. Say your finished bore is 3.500 you should have .003-.004 piston clearance(piston skirt would be 3.496-3.497)
 
Need to measure the piston diameter at the correct location.----New pistons are tapered.-----Old pistons will be useless to get clearance information.----Why is this motor getting this " rebore " work done.??
 
WOW!! He asks for info and gets great help and then becomes rude when Racerone tries to give him additional help! I gess the majority of folks are appreciative and pleasant. Guess we'll have to be content with helping them.
 
I seen this coming. After I said SOUNDS GOOD. I answered that other part of the question that was a condescending question with plenty of question marks, much like your comment. Not all of us are wandering around clueless waiting for god-like people to help us. I have extensive experience across many areas, built many websites and moderated many forums. Grow Up.
 
I guess when we respond to posts, we have no idea if we're talking to a 13 year old boy who just used his money from mowing lawns all summer to buy a small motor for his rowboat, or if we're talking to an experienced mechanic, or for that matter an accopmlished web designer, so we try to provide all the information we can to help folks. It's free advice and you got more information than you asked for. Not trying to insult you, just trying to help you.
 
The why question is critical. Something led to the cylinder damage, eh. The source of the problem needs to be found, or it could happen again. For instance a motor may be running too lean from a partially plugged main jet. This is not uncommon. We donate our time to help others, the only thing we get out of it....at least me....is self satisfaction from my 57 years of marine experience. Oldsaltydog makes a very important point....most often we have no idea of the experience of those asking questions. The nature of your question was such that anyone could find the answer using the cell phone to call a machine shop, or independent marine repair like myself....or google it up on the internet. Sorry to say it, but you may have built dozens or hundreds of websites, moderated many forums....just like my brother, Frank....but that doesn't give you the right to insult our members. Sorry, Racer....you deserve better than that, and thanks for everything you do. Im still learning after all these years....not only mechanics, but trying to figure out human nature.
 
I am far better at building motocross race bikes, houses, cars and large-scale computer systems than I am at web development. I do appreciate the responses I got back and passed it on to the meticulous mechanic with the right equipment to get the .030 bore done.
Thanks OldSaltyDog , Get over it TimGuy. I'm out.
 
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