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Discussion Starter #1
I finished assembling my 700 engine and started it up. Runs good, but after looking at my manual, I didn't check which way I assembled my pistons. I says to face the arrow on the bottom side of the piston to the exhaust port. I didn't check this. Is there a way to check without taking the heads, and cylinders off? What happens if the pistons are facing the wrong direction?

Thanks
 

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If you take off the pipes you can probably get the piston into a position where you can see the top. Might have to use a small inspection mirror and flashlight. I'm not sure what could happen if it isn't. Maybe the rings will catch on a port and break.
 

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it shouldnt run right if your piston is in backwards,,, I would pull the plugs to look before pulling the pipe. If you still cant see,,, pull the head. better to find out now than while your on the trail.

Better safe than sorry.
 

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Pretty sure Thundercat900 is correct. Ring ends in wrong position will cause engine
damage like you just repaired, due to rings catching something and breaking.

It is pretty easy to see arrows on new pistons using small inspection light thru
the spark plug holes.
 

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Discussion Starter #6
Thanks guys, I will see what I've got and definately turn them around if backwards....hey, I've got a 50/50 shot right......
 

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it shouldnt run right if your piston is in backwards,,, I would pull the plugs to look before pulling the pipe. If you still cant see,,, pull the head. better to find out now than while your on the trail.

Better safe than sorry.[/b]
true, sometimes it messes up the port timing, by leaving one uncovered or covered up at the wrong time.
 

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If the locating pins being loose (and allowing the rings to turn) was a problem, then assembling the pistons wrong way around will be for sure as well. I don't know about the 700 engine. However, on any engine which has basically symmetrical skirts, it will run even when the pistons are turned 180 degrees. What uou can be sure of is that; one, you will almost certainly hook a ring end - they should never pass through any of the ports; and two, if the ring ends end up on the exhaust ports, that in itself will surely cause problems due to heat, and/or carbon issues even in the very unlikely event that the ring ends don't catch first.

Basically, without trying to remember the rule about piston marks, the ring ends should face away from the exhaust side. (And, of course, the rings are marked in the top side near one of the ends.)
 

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Discussion Starter #9
ok, got lucky, removed the heads and both pistons were turned the correct way!! I even removed the exhaust and verified that I could not see the ring split through the exhaust manifold.

thanks
 

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see,,, better safe than sorry!! Glad to hear you dont have a lot of work tied up into putting them back in,,,
 
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