Super Jet can you flip reeds???

[nbatch95]

Are you saying there is something wrong with having lightly oiled bores on a new topend prior to startup? As in, something bad will happen?



Why?

Not saying you can't lubricate the cylinder walls but the chances of your rings not seating properly are a lot higher when the cylinder walls are lubricated prior to start up. Just did a top end on a 09 sj that was freshly done by someone else took it apart and it had lots of blow by from the rings no seating properly.

Only a recommendation. Everyone does stuff different. This is the way I roll and its never failed me. This info was from my machine shop guy that has tons of two stroke experience. I have pictures of the pistons ill try to post.

 

[nbatch95]

Also think about the amount of lubrication your cylinder gets from a 50:1 fuel air mix. It's not a four stroke engine that is lubricated by oil. The only lubrication it gets its entire life is 50:1 fuel air mix! In vapor form! Not much lubrication.

 

[Matt_E]

Not saying you can't lubricate the cylinder walls but the chances of your rings not seating properly are a lot higher when the cylinder walls are lubricated prior to start up. Just did a top end on a 09 sj that was freshly done by someone else took it apart and it had lots of blow by from the rings no seating properly.

Only a recommendation. Everyone does stuff different. This is the way I roll and its never failed me. This info was from my machine shop guy that has tons of two stroke experience. I have pictures of the pistons ill try to post.

That blow-by should show up in a compression test, presumably?

If I recall correctly, sign of proper break-in is a slight increase in cranking compression, indicating that the rings have seated. You might see it go from 175 to 180 or 185. Right?

 

[nbatch95]

Yes and the op said he put in a new top end and after one ride lost comp. blow by is my guess.

 

[Matt_E]

I disagree - I've done a few topends over the years, always with a light coat of oil. Never a problem. I don't see how the rings not breaking in due to oil (and that in itself is questionable) will lead to a 40 psi compression loss.

But let's wait for the OP to get back and see what he has to say.

 

[nbatch95]

Like I said before everyone does stuff different. Especially when it comes to building engines. Only a suggestion. Do what you want.

 

[Idok]

I disagree - I've done a few topends over the years, always with a light coat of oil. Never a problem. I don't see how the rings not breaking in due to oil (and that in itself is questionable) will lead to a 40 psi compression loss.

But let's wait for the OP to get back and see what he has to say.

this is the way we do it here as well.......

you should always have a nice thin light coat of oil on a freshly bored cylinder.......the raw sleeve will corrode in no time

 

[nbatch95]

Since all are saying my way is the wrong way what makes yours the right way? What is the need for oil on a cylinder that does no use "oil" for lubrication?

 

[nbatch95]

this is the way we do it here as well.......

you should always have a nice thin light coat of oil on a freshly bored cylinder.......the raw sleeve will corrode in no time

Obviously if you plan on letting a bare piece of steel to sit on the shelf for and amount of time it should have something on it to keep it from rusting. I clean it with degreaser first then put it together dry.

 

[TheBuzzard]

Obviously if you plan on letting a bare piece of steel to sit on the shelf for and amount of time it should have something on it to keep it from rusting. I clean it with degreaser first then put it together dry.

all 2 and 4 cycle engines use oil to lubricate everything including the cylinder bores and pistons/rings going up and down in them. you obviously have no technical training or schooling in the field of mechanics. thats okay too, but dont try and tell somebody that knows what they are talking about, that their way is incorrect. i dump oil all over everything when it goes together. in the automotive field, its called ASSEMBLY FLUID that gets put all over every moving part upon assembly, so that there is never a second that anything runs metal to metal before OIL lubricates it. excess oil never hurts anything. it may smoke like a SOB when it first starts, but its getting lubed.

 

[TheBuzzard]

and after a cylinder is bored and honed, its supposed to be washed with soap and warm water. you can actually watch it rusting and turning brown in your hand if you dont get oil on it fast enough.

 

[Matt_E]

Since all are saying my way is the wrong way what makes yours the right way? What is the need for oil on a cylinder that does no use "oil" for lubrication?

I am not sure what the point of arguing is if you think that a 2-stroke cylinder doesn't use oil for lubrication.

 

[nbatch95]

You used automobile engines as an example once again a totally different type of engine. I never stated anyone was wrong I simply stated my way of assembling a top end. Your the one saying someone is wrong. Your the ones that make these forums useless. My statements are simply opinions but opinions are not granted on this forum so I'm out.

 

[TheBuzzard]

opinions that are incorrect are useless and often harmful. if you dont KNOW the answer, dont give an incorrect answer that you are unsure of. listen and learn

 

[ProSouth]

Spreading incorrect engine assembly methods are what makes these forums useless. Novody jumped on you or got hostile. Nobody wants you to leave, hell the buzzards still around. Everybody's wrong sometimes. Don't sweat it.

 

[nbatch95]

Once again my opinion is wrong. I stated my opinion what makes it wrong? I explained my method explain yours.

 

[motobehrens]

batch95 isn't necessarily wrong, it just isn't really as common as it used to be. There are plenty of old schoolers who would assemble dry, with the theory it would help break in quicker, and they all claim to have engines that run as long or longer than wet assembly, with no visible issues upon tear down.

Maybe that theory is right, but I don't subscribe to it.

 

[ProSouth]

when its coated, the piston rings will scrape off the excess it doesn't need. 2 strokes can cold seize. start it up dry and if the cylinders and pistons dont warm up evenly, i can imagine it would be worse with dry cylinders. say you have a lean condition or an air leak, and your engine begins to diesel, i'd imagine it would be worse with dry cylinders. Im ASSUMING you turn your motor over quite a few times and stare at it like me remembering everything you did trying to assure yourself that its correct. If so, then that oil you put on the skirts will lube the cylinder walls a bit also. so you are kinda lubing half the cylinders.

 

[motobehrens]

As soon as it starts, the walls are lubricated, even if assembled dry.

If you are lean or have an air leak or your engine diesels, you have bigger issues anyway.

I put alot of oil on my cylinder walls when I assemble, and break them in hard. Next one I'll build dry, just out of curiosity.

 

[nbatch95]

when its coated, the piston rings will scrape off the excess it doesn't need. 2 strokes can cold seize. start it up dry and if the cylinders and pistons dont warm up evenly, i can imagine it would be worse with dry cylinders. say you have a lean condition or an air leak, and your engine begins to diesel, i'd imagine it would be worse with dry cylinders. Im ASSUMING you turn your motor over quite a few times and stare at it like me remembering everything you did trying to assure yourself that its correct. If so, then that oil you put on the skirts will lube the cylinder walls a bit also. so you are kinda lubing half the cylinders.

Why would you be starting a new motor with an air leak, or a setup that could in any way be lean enough to make a fresh motor ping?