I guess it’s new rings ?

[CP241]

I see what you’re asking. It helps to have the graphic to reference

What that .004 is referring to is the cylinder being out of round. A1 and C1 are perpendicular. As are A2 and C2. That is telling you to check the bore top to bottom cross ways from each other. If they’re more than .004 difference then the cylinder is egg shaped and must be bored.

The 2.519-2.521 is the bore spec.

If either of those are out of spec, then it needs to be bored out and you’ll need to buy oversized pistons and rings. You’ll need to make sure to buy the pistons and rings BEFORE taking it to the machine shop for boring. They won’t do it without the pistons and rings, and they’ll file the rings if necessary to ensure perfect fit.

Any machine shop that will bore a cylinder WITHOUT the pistons and rings will never see a dollar out of My wallet…

[Cartmaster]

Basically, that .004 difference would be telling you that the bore is tapered or oval and needs reboring to return it to a true cylinder, even within spec at its widest. If it can be rebored within the upper limit, then standard rings can be used. If as CP says, there is pitting, then the rebore will need to be oversized and + rings are needed to match the new bore size depending on how much metal is being removed. Any pitting or scratches will need to be gone and this will determine final bore and ring size. I am assuming you may be on a tight budget and looking for the least expensive option. To be honest, the best costs will be a full rebuild to spec on the whole engine in one go or you will be feeding many more dollars into it over time.

We are not trying to argue with you, just trying to advise on the long term return for your efforts. If you strip the engine down and most else is within spec, the your best option maybe to do an exchange with a reputable re builder. I hear Motors and more are excellent and you have probably already been advised of this option.

I see CP beat me to it 😆

[CP241]

Originally Posted by Cartmaster

I see CP beat me to it 😆

slow day at work…

Not to mention, my cart is electric now to boot

[Cartmaster]

But CP, I think we are getting somewhere though. I cant see the images well on my fone but I take it you can see damage to the bores.

[CP241]

Originally Posted by Cartmaster

But CP, I think we are getting somewhere though. I cant see the images well on my fone but I take it you can see damage to the bores.

It can be hard to photo so hard to be sure, but it looks like pitting in the cylinders to me. Which would indicate some sort of moisture was in there and the cart sat for a long time. If you can’t feel it with a fingernail then usually you can hone it out, as long as bore is still within spec. But that doesn’t look honeable to me.

[Cartmaster]

I think he said the previous owner kept it in a shed for ten years, so I reckon you are on the money.

[Tommybh]

Okay so piston you wall clearance brand new is .0008-.0023 if piston is 2.519 and bore is 2.51 wouldn’t that give me within new engine tolerance at .002 max wear says .0038

[CP241]

2.519 is larger than 2.51

You will need to remove the piston and measure them. And then measure bore as described in the manual to make sure it’s round.

[Tommybh]

Sorry cylinder 2.521 and piston 2.519 gives .002 piston to wall clearance max wear is .0038 piston to wall .. if all checks out then standard be good? I found a source for the oem ones the website you sent .. if it were up to me I’d bore it wife thinks it’s a money pit and is hard to convince to spend a few extra dollars and get it right .. local shop wants 200 to bore

[Tommybh]

Haven’t gotten around to anymore work on cart but does anyone think that the oil around the intake valves is suspicious? Or is that normal if rings are bad it matches the side of piston that is also wet