Rant! Engine Assembly, Read this Newbs.

[tarzan]

I am reading here where a lot of people recommending different kinds of sealers for a head gasket. Why would you need that. If you prep the head and cylinders properly, dry is all you really need.I have had no problems this way.

Yard Dogg, how did you repair your head gasket in order to re-use it?

[TopCatGr58]

I am reading here where a lot of people recommending different kinds of sealers for a head gasket. Why would you need that. If you prep the head and cylinders properly, dry is all you really need.I have had no problems this way.

Yard Dogg, how did you repair your head gasket in order to re-use it?

Hey Tarzan,

Most of us that are doing a major top end job with new pistons and such would most likely use a NEW head gasket and therefore would NOT use any sealant. It's the folks that are tearing their heads down to repair a damaged valve or excessively leaky valve seal and such, and then putting it back together trying to save some $$.

T.C.

[tarzan]

Hey Tarzan,

Most of us that are doing a major top end job with new pistons and such would most likely use a NEW head gasket and therefore would NOT use any sealant. It's the folks that are tearing their heads down to repair a damaged valve or excessively leaky valve seal and such, and then putting it back together trying to save some $$.

T.C.

Ok, I get it now TC. I misunderstood and thought he put sealer on a new gasket.

[BA80]

Silicone sealants really should not be used anyplace that it is around engine oil. Pieces of excess sillycone get squeezed out during assembly, break loose and clog oil passages. Yamabond/Hondabond/Threebond are the only products I will use around a motor.

Dry gaskets and Indian Head shellac are my faves. Yeah, I know, it's old school.

I almost forgot about Hylomar. Good stuff. Used for assembling Rolls Royce motors. 'Nuff said.

No way that that stuff can get into oil passages. Could possibly clog the oil pickup screen but it would take quit a bit to do so.

In order to get into oil galleys it would first have to pass through the oil pump pickup screen and if it made it through there it would have to pass through the oil filter.

Just sayin'

[TADracer]

Another poster mentioned coppercoat spray for the head gasket, and I just reinstalled my head with the spray. Is that a mistake or a difference of opinion?

I'm the other poster and I have used Copper Coat many times on XS11 motors. Believe me, loHo, I do not believe you have made a mistake. The main part you are actually trying to seal on these motors is the steel flame ring around the cylinders. The Copper Coat does an excellent job on that and if you ever remove the head you can easily remove the gasket in one piece. In a pinch I have even re-used a head gasket and it sealed again just fine. As far as any copper particles getting into the motor, the oil is filtered prior to distribution and even if a particle or two gets into the oil stream, copper is a softer metal than bearings, gears, etc.

Thats been my experience and I have had great success with it.

[Yard Dogg]

When I started out with the new head gasket, I thought about installing it dry, but I'd read other posts about having leak issues around the oil galley, so I sealed it there. When I took the head back off, the new gasket tore into pieces where I'd sealed it. The new gasket was of crappy quality with the felt surface. The old gasket was very nice quality and seemed to be made of a soft metallic. I didn't use copper coating as I normally would have due to the soft metallic nature of the gasket. After the bike heats and runs a few cycles, I'm sure it will be sealed fine. I just cleaned it with alcohol and sealed around the oil galley. I didn't end up using a gasket at the base and used Ultra black instead. I've had great luck with ultra black over the years and use it on everything. I agree that it would be hard to get a blockage due to the sealant. I try not to use too much sealant cause I really don't want it to squeeze inside the engine. On machined surfaces like what these bikes have, I apply about a 1/16 - 1/8 inch bead depending on how wide the surface area to seal is, then I smooth it out with my finger.

[natemoen]

There are no pressurized oil galleys that run through the head. The only place that oil passes through the head is the oil return through the cam chain tunnel. The likelyhood of oil leaking there is very very slim, there is no pressure and the oil doesn't pool up at the seam.

Yamaha had a separate seal that they originally put around the cam chain tunnel but then realized it was useless and got rid of it.

[Yard Dogg]

The cam chain tunnel is where people say they had leaks. I called it the oil galley.

[natemoen]

The cam chain tunnel is where people say they had leaks. I called it the oil galley.

I highly doubt it was leaking from that seam. Most likely it was really leaking from the cam chain tensioner and blowing through the fins and the unknowing people just assumed it was coming from the head gasket. The oil can pool up some and leak into the cct and then it dribbles out the front of the cct or around a poorly sealed cct.

[BA80]

Valve cover gaskets will fool you too. They will leak arond the #2 or #3 and the oil will drain down through the spark plug well drain holes and it'll appear the oil is coming from the head gasket or exhaust prorts.

Doc's SG was leaking from the banjo bolt that attaches the oil transfer tube to the head and it looked like the head gasket leaking oil. It was running all the way around to the front of the engine in the fins.

[Yard Dogg]

Here's another one to watch out for. If you split your cases for a total tear down and reassembly, don't forget to put the little starter gear in before you do anything else. I have to split my cases again cause that little bugger has to go waay down in the center of everything. Every machine has it's learning curve, I'm getting my experience on this bike for sure.

[BA80]

Man am I learning my lesson today. I'm reassembling my engine and causing myself a lot of grief. Last night I installed my jug and head on the upper case half thinking I could put the pistons in through the bottom. NOPE! Pistons will not fit between the main bearing journals. So I think, okay, I'll just take the head off and put em through the top, NOPE, after destroying my new head gasket cause I used Ultra Black, I discovered the rods won't fit through the cylinder holes, WTF! I have never come across an engine that the rods were too large to fit through the cylinders. So now I will have to destroy my jug gasket and make a new one. Luckily, I still have my old head gasket and it's in decent shape, better quality. Let this be a lesson to those of you who make too much sense. I'm sure there are others doing engine rebuilds this winter also. Pass this valuable info along to them so they don't make the same mistakes, thank you.

Here's another one to watch out for. If you split your cases for a total tear down and reassembly, don't forget to put the little starter gear in before you do anything else. I have to split my cases again cause that little bugger has to go waay down in the center of everything. Every machine has it's learning curve, I'm getting my experience on this bike for sure.

A couple things to add to that "I'll never do that again" list.

[Diskman01]

Protip:

Use an old clothes iron to flatten out rolled up gasket material.

I have an old beater iron in the garage for just that.

Do NOT use the iron found in the house. You WILL get yelled at.

[natemoen]

Protip:

Use an old clothes iron to flatten out rolled up gasket material.

I have an old beater iron in the garage for just that.

Do NOT use the iron found in the house. You WILL get yelled at.

I always get yelled at anyways whether I use hers or mine, so whats the diff......

[Diskman01]

Cereal box cardboard makes for GREAT gasket material.

Seriously. Made a few in a pinch. Thermostat housing gaskets from cutting up a cereal box saved my bacon a few times when I was younger.