Yong Heng piston replacement "piston spacer"

[rodjava]

I am replacing the complete piston assembly with a new one from Ebay. I noticed that the old piston has a plastic spacer where the piston rod attaches to the piston. The new piston assembly DOES NOT have this plastic spacer.

Is it reasonable to think that the spacer is not needed anymore?

 

[MEC17670]

I believe by looking at the gap between the connecting rod and the housing , I would put the spacer in. Alittle slop is fine but alot of slop isn't. Imo.
Let's us know on your decision and out come.

 

[rodjava]

I got some good intel from an experienced Yong Heng user who said the spacer is not needed. Makes sense since the "new complete" piston assembly did come with a spacer. We both think the spacer might bind the movement of the top of the piston which leads to the failure at the crank arm.
So, I reinstalled the piston assembly without the spacer and everything is working properly. I will report back if a problem with the piston reoccurs.

 

[Gerry52]

On the older one it looks like a gap was left on the connecting rod for a spacer. On the new one there is no such gap. How would you even add one if that's what you decide?

 

[rodjava]

On the older one it looks like a gap was left on the connecting rod for a spacer. On the new one there is no such gap. How would you even add one if that's what you decide?

Gerry, as shown in my picture, there is definitely a gap and the piston rod can move around. With the piston inside the cylinder head and the rod end connected to the crank shaft, I don't see a purpose for the spacer.

 

[Gerry52]

I think you misunderstood me. The older one, where the spacer is, it looks like the connecting rod was machined with a recess or notch to allow for the width of the spacer and for the depth of it also so its surface is flush with the surface of the connecting rod. The "engineers" must've felt it not necessary on the newer one. Once connected to the crank, the piston up in the cylinder should keep it centered with little to no range of movement on the connecting rod. Did I make sense?

 

[heavy-impact]

No need for the spacer.

 

[Fly]

Garry you need the spacer, believe me. Just because they did not send one with the new one means nothing.
if there is that much side play you indeed need it. I know what I,m saying with out going in to why. Just install
it on the same side it came from.

Fly

 

[Glem.Chally]

When you assemble it the crank is directly below the center of the cylinder. If the small end of the con rod is so pooched its hitting the piston sides you have bigger problems.

 

[heavy-impact]

I've had 3 yong hengs apart and none had the spacer. They also had zero wear on the piston pin or either rod end. One was three years old. I don't know the age of the other two. The updated piston/rod assembly that I installed in mine didn't have a spacer either. All the parts were interchangeable so I said no need for the spacer.