General tune up and cleaning out the muffler and exhaust ports. All pretty clean and looked good but I noticed the second ring's gap was visible in the exhaust port. Is this bad? Seems like the gaps should be on a solid part of the cylinder wall. Older F engine with normal use, runs fine, but this kind of worries me. Thoughts?
#2
Russ2251
Some 2 cycle rings are pinned to prevent rotation.
I cant remember for the life of me if rings are pinned on the model F or not.
They probably aren't..given the fact that you can see the gap.
I would not worry about it.
If they were going to hang and snap, it would have happened long before now.
I will check further, if only for my own curiosity.
Edit:
They are not pinned...as reassembly instructions ask for them to be staggered during assembly.
If they were pinned, staggering would not be necessary.
Duraforce (model E) rings are pinned.
#3
AnthemBassMan
My 1973 D600 engine is the same way. When I checked the exhaust ports in the beginning of June, one of the rings was near the left port.
You could, I suppose... but why would you want to?
#6
AnthemBassMan
It’s probably possible, but may just end up back where it was over time. If you don’t see any scoring in that spot of the piston, then it should be just fine as it is.
L8R,
Matt
#7
Russ2251
Rings do rotate, unless deliberately prevented from doing so:
My 1973 D600 engine is the same way. When I checked the exhaust ports in the beginning of June, one of the rings was near the left port. View attachment 39246
Seeing that and the obvious long term use there I'd guess there's nothing to worry about. These little mowers sure make the most out of that 4 hp, mow down a hay field I'd guess. Thanks for the info!
#9
AnthemBassMan
You’re quite welcome. I love the D Series engines. Not quite as powerful as the F Series, but they have some serious grunt for only being rated at 3.5hp. Gotta love 2 stroke torque!
Do not worry about this. the ports are made to prevent the rings from "hooking." They are also bridged to also help to prevent cylinder distortion due to temperature changes. In some engines, the ring(s) are pinned to prevent the ring gap(s) from moving into the a position where they could become hooked in a port.
