Leaking head gasket on 77D

XS650D

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Have had a leak on the front right cylinder just above the exhaust valve for a few seasons now.
I changed the outside 2 stud rubber washers for the copper ones.I only did the 2 outside on each cylinder
I read that those were the problem ones. Should I have used the brass ones instead and done all 8. I find the torque backs off some for some reason.I guess the motor,s gotta come out to change the head gasket . Should I just change all 8 head bolt washers to brass and retorque everything and see,
Strangly thats the only side thats ever leaked. Maybe there a bit of warpage in the head on the right cylinder.
 
Have had a leak on the front right cylinder just above the exhaust valve for a few seasons now.
I changed the outside 2 stud rubber washers for the copper ones.I only did the 2 outside on each cylinder
I read that those were the problem ones. Should I have used the brass ones instead and done all 8. I find the torque backs off some for some reason.I guess the motor,s gotta come out to change the head gasket . Should I just change all 8 head bolt washers to brass and retorque everything and see,
Strangly thats the only side thats ever leaked. Maybe there a bit of warpage in the head on the right cylinder.

The four outside studs are the only ones that have to seal oil, the copper washers are just as good a brass. The inside washers are steel and are just fine as they are. My understanding of why the head gaskets tend to leak, has to do with the factory rubber sealed washers compressing over time and losing torque. Then the head gasket usually leaks above the exhaust ports. Change the outside washers and re torque the head and sometimes you can stop the leak.
 
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Have had a leak on the front right cylinder just above the exhaust valve for a few seasons now.
I changed the outside 2 stud rubber washers for the copper ones.I only did the 2 outside on each cylinder
I read that those were the problem ones. Should I have used the brass ones instead and done all 8. I find the torque backs off some for some reason.I guess the motor,s gotta come out to change the head gasket . Should I just change all 8 head bolt washers to brass and retorque everything and see,
Strangly thats the only side thats ever leaked. Maybe there a bit of warpage in the head on the right cylinder.
Once apart, have the head and jug surfaces checked for flatness and inspect for surface damage. If you keep losing torque there’s a possibility that the studs are elongating with applied torque (someone in the past could have over torqued them). Could check studs too while it’s apart.
 
May be a dumb suggestion
But I have been present when experts made the mistake for Excavator tracks
Not tightening bolts with the right torque.
Right spec Torque according to manual .
Here using the right criss cross pattern
.And Using tools that delivers that torque.
Some times oil is commended on Bolts

Even if that is done a few re torques can be needed as in this case
When washers been replaced
If this was me I would I would tighten to torque specs with a checked torque wrench
If it keeps on coming loose that I would assume means the threads are coming out in case.

On a side note there exists a tightening pattern ..
And I read somewhere that in some cases also exists Loosening pattern .
So the stress / Contact pressure relaxes evenly ..not warping the object
It made my hair at the back of the neck stand when here people loose one nut at a time replacing washers
I have no doubt it is working here given the Experience here.
I have seen methods used -- gggGary is strongly recommending for the re tightening.
 
Actually when changing the outside washers I did do one at a timer ,read here somewhere it was ok to do that.
Actually I think my Haynes manual stated ok to do it that way also. I have retorqued head twice since approx 100 miles after. I did add a lil light weight oil to the threads when replacing the
washers to all 8 head bolts. Im pretty sure I loosened and retightened each bolt in the proper sequence.Should I have not loosened each bolt
before each retorque?
 
Actually when changing the outside washers I did do one at a timer ,read here somewhere it was ok to do that.
Actually I think my Haynes manual stated ok to do it that way also. I have retorqued head twice since approx 100 miles after. I did add a lil light weight oil to the threads when replacing the
washers to all 8 head bolts. Im pretty sure I loosened and retightened each bolt in the proper sequence.Should I have not loosened each bolt
before each retorque?
Loosening one nut at a time is the way I do it. Consider.... when you disassemble the head, the book says to remove the 8 nuts. It doesn't say anything about loosening in stages or any such.... just remove. So.... when you start you have 8 tight nuts and you remove just one. Does that cause any warpage or other problems with the head? Nope, it doesn't.
That's exactly what you're doing when you replace the washers one at a time. And that's what you do on a retorque... loosen then retorque.
 
I use oil.. anti-seize works too. Here's an excerpt from the top end thread in TECH.

Let's talk lube torque vs. dry torque here for a moment..... there's many a discussion here on the forums about whether to install the head fasteners dry or lubricated. The early XS manuals specifically stated "lubricate all head fasteners with motor oil." The later manuals such as my 78-80 do NOT say to lubricate. Quiet the dilemma huh? An advantage of lube torque is that it's easily repeatable, more accurate and smoother because of the reduced friction in the threads. BUT....... that reduced friction also means that for a given torque, you're loading more tension into the fastener. In some cases, a lot more....as much as 20-40% more tension. Yikes!! Add to that the fact that well used fasteners have threads that are more polished because of numerous tightening and loosening cycles... and therefor have less friction to start with, and it becomes obvious why older hardware tends to strip its threads more easily when a lubricant is added.
So.... here's how I do it. I lubricate the fasteners with motor oil and use less than the specified torque. For the studs I went 8ft-lb on the first torque, 16 on the second and a final torque of 27ft-lbs. The bolts got 5, 10 and 14ft-lbs.... and the small bolt at the rear got a snugging on the first go, 36in-lbs on the second torque and a final torque of 72in-lbs.
 
Actually when changing the outside washers I did do one at a timer ,read here somewhere it was ok to do that.
Actually I think my Haynes manual stated ok to do it that way also. I have retorqued head twice since approx 100 miles after. I did add a lil light weight oil to the threads when replacing the
washers to all 8 head bolts. Im pretty sure I loosened and retightened each bolt in the proper sequence.Should I have not loosened each bolt
before each retorque?

Is the Torque wrench OK ? --- If it is 100 miles in total more can be needed

I have seen a loosening sequence I Believe it was an Oilpan for a Honda 929 Fireblade
And is seen online

https://www.yourmechanic.com/article/how-to-remove-cylinder-head-bolts-by-spencer-clayton

Warning: Cylinder head bolts have a specific sequence that is used when removing them. Consult the manufacturer's specifications for the proper removal sequence for the engine being worked on.

This being ( old XS 650 ) most likely it is more stiff less optimized ..so Given the Experience here at the forum
Perhaps even in a service instruction.
It would work most likely.. . Loosening and oil on threads seems right. Service manuals often have that in the Work description and is good practice in most cases.
But differs between manufacturers orders.

But the phenomenon Exists and I think it would be better to follow the more careful ways to do it if possible -- to be on the safe side
and have it as a practice . The Airplane Boys should have seen it.

If the machine is old and have warped or scratched surfaces .a bit of Liquid Gasket and extra care tightening and loosening can help.

So

So.... when you start you have 8 tight nuts and you remove just one. Does that cause any warpage or other problems with the head? Nope, it doesn't.

Can instead be
So.... when you start you have 8 tight nuts and you Dont remove just one. You loosen them step by step in the same manner as you do Tightening them

I have worked with Excavators and Pipelines .. When a leak ... The first step was always to Tighten the Coupling / Flange ( Newer loosening ) .In most cases the leak then stops.
If it don't stop then next step is considered. Often these were under pressure so loosening is not a good idea.
I don't know the design rules for the head bolts but I would assume over tightening is avoidable in the sense that some Margin is there
 
Its still pretty cold in my garage, maybe 5 degrees Celsius (40 Degrees F ) Does it matter on Temp for doing
a Head retorque?
 
Its still pretty cold in my garage, maybe 5 degrees Celsius (40 Degrees F ) Does it matter on Temp for doing
a Head retorque?

I am going to take my bike out within a few days .. And I am going to Tighten the head bolts to Spec
I would expect the outdoor temperature 5- 12 range Celsius. Then
And doing it on a cold engine.
About a year ago I started after a Rebuild and cant remember exactly if it has been one or two re torques after that.
I Believe 2
It was the outermost left and right side that needed ..surprisingly more .But this was with a New Head gasket
I touch the bolts every year ..When starting just to be sure nothing is loose .. It happens
Since it was a rebuild last year I will use the Torquewrench ..And I will do it again come warmer Climate.
If it is best practice or not I am not certain about I am doing other service at the same time and the Tank is off so it is simpler to do it now
Not that I would start it not having done it .
 
Warning: Cylinder head bolts have a specific sequence that is used when removing them. Consult the manufacturer's specifications for the proper removal sequence for the engine being worked on.
Nope. From the 78-80 service manual...


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