Can anyone tell me the direction the piston sleave goes into the cylender? This is my first nitro engine, I had the head off and the sleave out and want to get it back in correctly. There is a knotch at the top and it looks like it is an alighnment mark. I am working on a K&B 3.5 Outboard engine.

Thanks for you help

Nick

Is there another mark on the engine that willmatch the mar kon the sleeve?

If the engine is used, look for the discoloration of the exhaust port. If it's new, I think exhaust is the higher of the two ports on the sleeve_Bob

There are no marks on the cylinder or head to match it to. There are 5 holes in the sleeve tough. If I knew which one is the exhaust, I could line that up?

Nick

The exhaust will be nearest the top.

I hate to say this, but line up the exhaust port on the sleeve to the exhaust headder. Now, another problem would be lining up the piston... Is there any mark on it? It should fit 1 way properly.

What may be best is to go to http://www.modelengine.com/kbindex.htm and drop them a line...

Normally I mark the back of the rod before the engine comes apart to match the wear patterns. Why is the engine apart again?

When I got the engine it was in peices. I had to get gaskets and screws for it and am putting it back together. I have another one here but didn't want to take it apart to compare.

If there are no heat marks on the piston either, you have no choice but to toss a coin and put the piston in one way or another. It should be ok_bob

Let's see if we can bring some reason to this thread. Bear in mind I am not looking at your engine.

The exhaust port will be bigger than the inlet ports. The top of the exhaust port will be higher than the top of the inlet ports. You said there were five holes around the liner. There is a possibility that the exhaust port may have a centre bar/web, in which case the openings either side of this bar will be identical. If there is a web and if the engine is ringed this web is to prevent the ring ends from catching the top or bottom of the port. If the engine is not ringed it may be just for strength. The ports in the liner will match the transfer passages and exhaust opening of the crankcase in only one position. Slip the liner in and rotate it until the matchup occurs.

Obviously the piston wrist pin hole must face fore and aft. So that leaves only two ways it can go in. If there is a cutout in the piston skirt the cutout probably faces the front of the engine. Look at the crankpin end of the rod. There may be a chamfer around one end of the crankpin hole. This chamfer probably faces forward. It is to clear the rad where the crankpin meets up with the counterbalance.

What I have described are 'Typicals' I remind you again I am not looking at your engine.

Ed S

Thanks for all of the replies. Ed you description is pretty much right on. Thanks for being so detailed.

You guys have been a great help.

Nick