Inserting pistons into the cylinders, A one & a two...

[KA1J]

Well, we got them in last night. We used the squeeze method after trying the hose clamp idea with less than stellar results. I'm sure that's a good method but we didn't have the technique down to do it well. Since the surfaces were clean on crankcase & cylinders I just sprayed the base gasket with a thick layer of aluminum paint on both sides, let it dry & we were good to go. Didn't use any RTV as it was suggested it's not needed if all is clean & it sure was.

I haven't put the head on yet will do that Monday when I'm back with the bike.

Getting closer!!!

[ViperRon]

Everyone has an opinion I respect all I see

I recently overhauled mine new rings and pistons. Wanting to keep the compression high and equal kept the bore tight and honed the cylinders to minimum making it a bitch to install pistonswithout moving ring position. Being the rings were tight I devised a new plan of attack for installing pistons. I installed all pistons in the cylinder then lowered the cylinder onto the engine. Starting with the two inner pistons I slid one piston down at a time till I could insert the pin into the rod and used a tool they suggest (threaded rod with nuts) to seat the connecting rod pin back into the piston. I lubbed the pin very lightly and as soon as all aligned it slides in easily. To put the keeper clips in you have to be careful not to drop it in the case but other then that its pretty easy this way. You will need some wood shims to set the cylinder on to keep it from sliding all the way down and its best to use something to hold the crank in place so it only moves when you move it. Also I did not install the gasket underneath the cylinder but I did put new 'O' ring gaskets that were a little oversize in arround the bottom of the cylinder and have not had any leaks. I would ask that if any moderator here see's a flaw in my method to let me know as I am new here on the site. I have rebuilt many engines before but was the first time working with The SX1100.

[KA1J]

Funny, there's that buyer's remorse kind of thing where you weigh options, consider finances & ponder what is best thing to do and than after you make a decision & follow through, you 2nd guess what you did and should you have done something else. Human nature... So in this case it's O-rings I'm reflecting on.

I'm wondering if my not replacing those base cylinder O-rings is going to be a future issue with some kind of leakage? The O-rings looked perfectly tight, the metal surfaces of the crankcase and cylinders are clear of debris, base gasket was sprayed with aluminum paint and the cylinder is now resting on the crank with the pistons inside, waiting for the head to be placed on & Acorns to be torqued.

At this point I always could raise the cylinders and put a layer of anaerobic or black RTV around the base of the cylinders if need be. Worse, I could remove the cylinders, find new o-rings somewhere and put them in & reseat the pistons but would all that be un-necessary? I don't have ready help to reseat the cylinder is the problem.

It seemed to me that if the O-rings were already tight in place, there is a good seal at the base and the head is torqued properly, that those O-rings are a red herring & nothing to be concerned about leaking. I also can't quite see how a leak from them would run & show itself with the gaskets in place.

For sure, someone else will follow this thread in the future and get answers to these same questions.

Thoughts?

[DiverRay]

O rings are synthetic rubber, and seem to hold up VERY WELL compared to other material. I don't think you will have too much of a leak problem. The seal is for "splash" oil, and if the breather is good, you should not have much pressure trying to force oil through that area.
I think you will find the cam chain adjuster leaking more than the base.

[ViperRon]

The 'O' Ring should not be an issue since you have put the Gasket on and paint works well sealing it but can be tuff to remove. I would leave it alone for now as as if it ain't broke don't mess with it. The other issue is i typically do not take a head off without replacing the head gasket. They never seem to seal as well when they have been removed. As a person stated you will probably have more issue with the Cam chain tensioner assembly. I have always cut my own gasket for that reason. I will suggest replacing the 'O' Ring that seals the cam chain tensioner. Sorry my reply was a little late but the method I used installing the heads I was much easier for me. One more piece of advice be very careful and precise when setting the mechanical timming make sure everything lines up before final tightning as the valves on these bikes have little clearance and you can bend them. Here is a picture of mine. Not on road yet! Sooooooooon! http://s1184.photobucket.com/albums/z329/viperron1/

[KA1J]

Ray & Ron, Thanks for the info. I guess I don't see with those o-rings where the oil is being prevented from going from/to; The cylinders are tightly fit sleeves so the barrier seems to be to the oil in the crankcase & the o-rings prevent it from seeping through the sleeves. If that's the case, the outlet would be at the top of the cylinders but that little bit of oil would be blocked by the pressure from the head gasket. I have no idea if that's the way it works, that's just what it seems to be to me.

As to close valve tolerances, I was going to go without the base gasket and use a sealant instead but since the head was shaved .005 I decided it wasn't worth the chance of interference between the valves & pistons.

I am replacing the head gasket; Lakecountydave sent a new one to me to fit an XS11 and I'll re-use the YICS part of my old head gasket to fit the YICS parts on my head/cylinder. I have a YICS eliminator in it already so it's almost a moot point.

The cam chain tensioner; I bought an extra auto tensioner from one of the list members & am planning to put that in, instead of the stock tensioner. I made a gasket for it & hopefully that'll be something I don't have to see leak. I'll check for an O-ring that fits the tensioner, not sure which kind to get but maybe NAPA will have one that matches.

Closer...

[ViperRon]

I think that the 'O' Ring is just to fill the void and apply an extra flexable seal against the gasket. I believe they designed that void because the cylinder goes into the block. If the gasket was a little oversize and when tightening it there was no void to squeeze into then it may tend to warp, wrinkle, or tear creating a leak.At times things are design standards that have built in overkill and no one ever really asks why they just continue the standard. I have seen this void on other engines and this is really the only thing as far as design that I can see it is for. So given that you have a tight seal on the rest of the gasket there should be no leak. All bikes have something wrong with them You just know what your thing is