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After cleaning up the front cylinder on Orleans, I still wasn't sure about the head gasket and decided to replace it anyway. MIght as well do it while I've got access. There seem to be a couple of gasket sealants "out there", however, and I was wondering if someone could point me in the right direction (which might include steering away altogether). There's the red RTV sealant which appears really to be a gasket maker (like for an oil pan); then there's some blue stuff, which seems more sealant-y. And then there's just the "coat it with oil, put it where it's supposed to go, and put the cover back on the cylinder." Anyone have suggestions?
 

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Cindy if memory serves me right (lol yeah right) I believe the red rtv is the high temp and the blue is mid heat range, I would say the red would hold up longer personally but lets wait for a second opinion...theres always indian head gasket sealer
 

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I don't know about the 750 but I've never used sealent on a head gasket.
 

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Discussion Starter #4
Cindy if memory serves me right (lol yeah right) I believe the red rtv is the high temp and the blue is mid heat range, I would say the red would hold up longer personally but lets wait for a second opinion...theres always indian head gasket sealer
What memory? Who are you?? Ha ha. The red is definitely the high temp, but i actaully saw no traces of any sealant when I pulled of the existing gasket. Given the oil leak, I thought, "Well, maybe they should've put something there," so I thought I'd better ask. I'm also replacing the o-rings on the spark plug retainers (which is the area most likely the source of the leak), so between the two, that engine oughta be good and sealed.
 

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HAWK
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You don't use any sealent on headgashets. I never have on all the motors I have built over the years.
 

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Discussion Starter #6
Works for me, then. I'll just go drop that one on, bolt 'er up, and call it a new head gasket.

Out of curiosity, though, when do you use sealant? Clutch gaskets? Uh..I'm trying to think where else we have 'em.
 

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HAWK
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You use sealent on rubber gaskets, like the valvecover. I would put some in the corners where it goes over the cam lumps and in the half moons.
 

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The headgasket requires no sealant. The only time I have used a sealant on the head area is when I was trying to get a little more horsepower. No gasket and surfaces sprayed with coppercoat then bolted togather wet. It raised compression but did nothing for reliability. It usually "blew" in a few short hours(sometimes laps) and made tear down much harder.
 

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If you are just doing the head gasket and not splitting the crankcase, the only place that you should need any sealant would be a small amount on the half moons of the valve cover. I use a product called "the Right Stuff". It has some type of fiber in it and isn't as slippery as RTV.
 

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There are two gaskets on the cylinders of our bikes. One is a metal gasket that is coated with a sealing material. This one requires nothing, the other one is a standard paper gasket. I used plain old Permatex on mine and have had no problems at all.
One word, be careful when torqueing down the smaller head bolts. Even with a torque wrench and well before I reached the recommended torque, I managed to snap one off and had to disassemble the head to get the stump out. It just "felt wrong" while I was tightening it. You will notice it if you ever snap a bolt off that while tightening, it just doesn't feel normal. That's about the only description I can give but those who have experienced this will know what I am talking about.
 

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Works for me, then. I'll just go drop that one on, bolt 'er up, and call it a new head gasket.

Out of curiosity, though, when do you use sealant? Clutch gaskets? Uh..I'm trying to think where else we have 'em.
Cindy -

ANy of the fiber/paper/material gaskets require sealant. Metal gaskets generall do not as they are designed to crush when torqued down, also why you can not re-use them.

Might turn the key today........

Jon
 

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Jon...did the key turn? And if so....???? :smiley_th
Cindy -

Today became today instead. Kind of forgot it was Christmas day yesterday, no work done.

Need to splice in the fuses in the stator leads. Hook up the starter and neutral switch lead. Install the exhaust system. Check everything again, then turn the key.

Will let you know.

Jon
 

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Cindy-Ok just to clarify, are you trying to make your own head gaskets or do you already have them?
 

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Discussion Starter #15
Already got 'em , although now I'm thinking that maybe it's not the head gasket after all. It's the rubber gasket that goes under the cylinder cover - the one that's rectangular in shape, but has two small arch-shaped pieces on the one end that sit perpendicular to the cylinder.

Does that help?
 

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Already got 'em , although now I'm thinking that maybe it's not the head gasket after all. It's the rubber gasket that goes under the cylinder cover - the one that's rectangular in shape, but has two small arch-shaped pieces on the one end that sit perpendicular to the cylinder.

Does that help?
Oh ok, i know on a car they are the valve cover gaskets. I think they would be the same on here. I would think you could make your own gasket for that with some gasket felt, except for the arch. not sure how thick it is. Keep in mind that area is subject to great pressure as the pistons move in and out of the sleeves and into the crankcase area.
 

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Discussion Starter #17
Ayers posted 'em as "gasket - head"...but it's rubber, not paper or metal. Given that it's sealing up an area that has oil running through it, I was thinking that one might do the same for that gasket as for the gasket on an oil filter - run some oil around it to make it more pliant and therefore create a better seal. But it seemed to snug into the valve cover head ok without an oil coating, so I haven't done anything more to it. Yet. And since my surge box is still on the garage floor, there's still time!! But I'm getting the sense that there's no need for any kind o' sealant, so perhaps I'll leave well enough alone for now.
 

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I was thinking that one might do the same for that gasket as for the gasket on an oil filter - run some oil around it to make it more pliant and therefore create a better seal.
I was always told you oil the filter gasket so when you screw it on, it doesnt bind, fold and therefore leak. But then again it was from a shade tree mechanic, so it maybe a myth.

If the gasket is pretty tight i wouldnt worry about it leaking then.
 

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Discussion Starter #19
He he... the guy who taught me to change my oil was a gentleman I worked with who had had a traumatic brain injury. To that end, however, he was still working as a mechanic, and had a series of steps that he'd go through just to make sure he didn't forget anything (e.g., if he was changing the oil in his own car, he'd leave the empty oil quarts out so that he didn't have to rely on his memory about how many quarts he'd already added). Kinda interesting strategy - and I actually had a non-brain-injured mechanic forget to put transmission fluid in my old Renault, effectively resulting in a mercy killing (I hated that car - it used to throw parts on I-76 outside of Philly).

I guess if something starts leaking, I'll know I need to go back in there and try a different approach!
 

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According to the Clymers manual, you should put a drop or two of RTV on the rubber valve cover gaskets where the half moons are and in the corners. Based on the picture you posted earlier, that is where I think the oil leak is coming from. I used the black, oil resistant RTV for mine and haven't had any problems so far. It was the same stuff I used to seal the crank case halves when I reassembled the engine.
 
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