Other Piston ring gap on the wrong side?

[Sasquachcrap]

Ok so I was putting my dads motor back together and I wanted some input on this. I know the arrow on top if the piston points to the exhaust. This puts the ring gap on the intake side (or close to it). The first piston I put on looked fine. The I started on the second and it's like they put the arrow on the wrong Side I the piston. If the arrow points to the exhaust then the ring gaps are in the exhaust port. This doesn't seem right. I checked the pistons that came out and the arrows pointing to the exhaust Clock the rings to the intake side. This is all I have ever known. It's like some one put the arrow on the wrong side of the piston. If I were to spin the piston around the ring gaps would be on the intake side, but then the arrow wouldn't be pointing to the exhaust. What do y'all think? Remember this is just on one piston. The front one is normal. Here are a couple of pics if they help. First picture is of the piston I believe to be right.

 

[Sasquachcrap]

Now some of the piston I think is wrong

 

[amitchell]

are the skirt widths the same below the ring gaps?

 

[Sasquachcrap]

I don't know I will measure.

 

[Sasquachcrap]

Piston skirts are symmetrical same with on both sides. I think I should just turn the piston around. And say screw the arrow. The piston couldn't have been cast wrong, but the arrow could have been marked on it wrong.

 

[OCD Solutions]

That would be my assumption as well but is it really worth the gamble? How long would it take to get another piston delivered?

 

[Sasquachcrap]

Would anyone run the ring gaps in the exhaust port. What is the design reason for them toward the intake?

 

[amitchell]

As long as all the features are the same compared to the ring gaps and just the engraving is wrong run them.

 

[amitchell]

Would anyone run the ring gaps in the exhaust port. What is the design reason for them toward the intake?

Never, they need the support from the bore all the way through stroke or they will catch.

 

[Sasquachcrap]

That would be my assumption as well but is it really worth the gamble? How long would it take to get another piston delivered?

I'm sure I can get another piston. No problem. But the piston is identical to the other except for the arrow. And if all I have to do is spin it around then I would just spin it. Has anyone ever seen pistons marked wrong? Now the wisco's I took out had skirts of different sizes from one side to the other.

 

[kevbo]

That was a Friday piston, I would use it. I have found pistons with cast arrows having the pins clocked nearly sideways.

 

[102nd7]

I'd spin it around and run it.

 

[DAG]

Yup, send the photos anf get replacement pistons. In the meantime flip them and run it

 

[JetManiac]

Next time tell your dad not to buy wsm pistons if there is another choice.

 

[Sasquachcrap]

I think I have just about learned my lesson with WSM Pistons. This isn't the first time they have shipped me something from the factory that has been wrong

 

[Sasquachcrap]

@JetManiac. I need a hooker Impeller removal tool and the rubber piece that goes in front of the impeller do you sell those and if so how do I get up with you to buy them.

 

[Sasquachcrap]

Well I got her back together. Spun the piston around. Every thing ran great. Lesson here is no matter what the arrow says,

Ring gaps split the intake port.

 

[restosud]

IMPORTANT!!!
check to make sure piston pin hole is centered.some pistons offset the pin for thrust issues and therefore cannot be installed backwards.
yams and kawi are offset so would think seapoos are as well.

 

[lakebum]

I had the same issue except I didn't catch it till after the ring grabbed the exhaust port and rolled. Trashed the bore and piston

 

[icecoled007]

I bought an 1100 where the arrow was wrong and the dealer proceeded to install it wrong. Ring grabbed the port and the new top end was over.


Made for a cheap ski for me