piston direction....

[icunvmytmaxx]

So I tore down an engine today for the first time. Pretty easy actually. My problem is, when I reassembled, I think I put the piston in the wrong way. This may be a stupid question, but which way does the piston go back in? This engine is great but it just ain't firing. I'm pretty sure this is my problem. Piston direction????? Help!!! Thanx a lot...

Anyone???? Come onnnnn... stooopid Nooobie needs help....Lmao!!!!

 

[DirtRider045]

What engine was it?

 

[MotoGod]

Most pistons only go in one way. If you put it in backwards, it will typically hit the backplate and break ;-) Every engine I have torn down, the longer side of the piston skirt faces the backplate (and usually the backplate is slotted to allow it to come down that far).

Might help to know which engine though so we can be sure ;-)

 

[Racer 1966]

Most pistons have a cut out on one side of the skirt(bottom edge),that cut out goes to inside for port clearance as the crank comes around.

 

[icunvmytmaxx]

It's an OS .15 cv-x.

 

[icunvmytmaxx]

My piston has no "cutout", just a little hole in the side of it. I'm guessing this goes in the sleeve so that when it cranks, it meets the hole in the sleeve? Super noobie to tearing down an engine.cause if I put it in one way, the hole in the piston has no purpose. I put it in the other way, when it cranks, it meets the hole in the sleeve. This must be the way I want it right? Which 2 holes are supposed to meet? The exhaust port hole or the other one? There is no significant mark in on or around this piston that tells me which way it goes...

 

[icunvmytmaxx]

Can anyone answer this?????? Man, just a quick answer is all I need....thanx in advance.

 

[MGT8.0owner]

I'm pretty sure the piston goes in so that the hole in the piston meets the hole in the sleeve...

This is why you always either take pictures or use a marker to put a mark on both the piston and sleeve so you know how they go together

 

[icunvmytmaxx]

I'm pretty sure the piston goes in so that the hole in the piston meets the hole in the sleeve...

This is why you always either take pictures or use a marker to put a mark on both the piston and sleeve so you know how they go together

Yea, I know, my bad for forgetting my camera when I was trying to "fix" this engine. There's obviously 2 ways this goes. One is the hole in the piston cranks up and meets with the exhaust hole. The other way is it just lines up with another spot on the sleeve opposite to the exhaust hole. Alls I need to know is which say it goes? Any info would be great.

 

[icunvmytmaxx]

I can't believe noone has an answer to this...all the knowledge on here??? HELP!!!!!!

 

[Racer 1966]

HERE's a pdf of the manual. Scroll down to the exploded view. It looks like it lines up with the hole in the sleeve. That's the way I would put it.

 

[icunvmytmaxx]

HERE's a pdf of the manual. Scroll down to the exploded view. It looks like it lines up with the hole in the sleeve. That's the way I would put it.

Thanx man....I really appreciate the info! That's all I needed to know..