piston rings, which way up?
 

Hi all, can anyone tell me the correct way to install piston rings on an xt. the set i have are genuine yam ones, but there are no markings on them to define which is top or bottom. most rings have some sort of marks but these are totally blank! any help please, T

As for ring location on piston the top ring is the chromed and the middle ring is darker in color.
regarding orintation in ring groove up/down they can be installed either way because the ring sides are square, rings that are marked have one side tappered or a steped groove to help with compression sealing.

the rings i have are not the same, one has square sides & the other has a slight taper on one outside edge(the darker looking one). does this mean i have the wrong set for my 3aj ? T

I don't know the xt models well enough to tell if you have the wrong rings, I was looking at a set of new oem rings for a 34L when I ansewed your question. Here is a link to Hastings rings http://www.hastingsmfg.com/Service%2...ring_types.htm See if your ring type is shown on the chart, They have a ton of engine building information in the service tips index.

Rings
 

The ring with the taper is the top ring. Taper should point to the top of the piston, ie. away from the pin.

The other one should have some mark on it; it can be very vague. Check the ends close to the slot. The mark should point upwards.

Auke

aukeboss is right
 

just to add what he said, i done mine last year and i think the rings are marked with the letter r for some reason, anyway, the r faces up and don't forget to oil the chamber before pushing the piston in.

Have you decided how you will install the rings T?

The chrone ring is definatly the top ring, the chrome resists scuffing from dust and grit in the combustion gases. The middle ring is cast iron( darker), if it has a taper on the outside edge it should be down, towards pin. This acts as a oil scrapper, Removing the excess oil from the cylinder walls on the downward stroke. Installing this ring increctly can increase oil comsumption considerably, it will actuall push oil up into the combustion chamber.

A difference of oppinion! when i built the engine, i put the bevelled ring at the top. but she smoked a lot when started after sitting over night, so i was reckoning the rings were on the wrong way round. theres definately no markings on any of the rings, have checked the part nos, and they are ok too. theres new valve seals on, bore has been honed so i reckon rings has to be the problem. what do you guys think?

If the bore is true and measured within the specs, it has to be a piston grove or a ring issue.
Here is a like to the hastings site that describes oil consumption with incorectly installed rings.
http://www.hastingsmfg.com/Service%2...stallation.htm

interesting site. so i go with the chrome ring at the top then? tapered one middle with taper facing down? grooves are fine so it can only be a ring issue. thanks guys.