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Discussion Starter #1
It is nut no 2 in the pic that is leaking.



Yesterday I torqued it down with some sealant but when I took a ride it is still leaking.



I should mention that the left cylinder is smoking and I have smoke (read exhaust pulses) coming out of the breather tube.

This engine should according to PO have been renovated 500 miles ago but he did not say what year this renovation took place.

My suspicion is that the bike has been standing in some moist shed on the kickstand for 5 - 10 years after this renovation. He said that the rings would bed in if I rode the bike for another 500 miles but I am starting to have my doubts.
 

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Sensei
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Znabb.... From your picture, it would be nut #1.....Regardless, it appears you do have a problem....Probably a bad head gasket....Likely bad (stuck) rings as well....
The definative test is a compression check........ ANYTHING less than 163 PSI per cylinder is rebuild time.....
Before you test, Please change the oil.... A bit of fuel in the oil (from leaving the petcock on or blow-by through a bad head gasket) can also cause the smoking to the exhaust pulses and eventually lack-of-lubrication problems (cam, tappets and journal wear)....
Please let us know the compression test results..... Run the test with the engine hot, and throttle wide open (coils disconnected and/or kill switch in "stop")
 

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In my case it was nut #4 that the P.O. had applied sealant to in an effort to keep it from leaking.

I'd take Steve's advice and do the compression check. You can read this page here on what I found when I took mine apart.

viewtopic.php?f=5&t=639&st=0&sk=t&sd=a&start=70
 

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I have seen 450 heads with casting flaws that allowed leaks.
Not common at all, but still possible - I've seen it several times. I know it caused me major headaches when I was wrenching my way through college.
Clean the engine well, spray the area with dry spray-type athletes foot powder.
It will pinpoint the exact location of the leak and washes right off.
 

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Discussion Starter #5
66Sprint,
Of course it is nut no 1. I mixed up front & rear on the engine. Good idea to make a compression check. Will go and buy a compression meter tomorrow and check it with engine hot, and throttle wide open. Will post the result as soon as possible.

MNellis,
You'r thread is like finding the motherload for me. As I will fix my bike this winter I got stuck over an hour reading you'r thread. Great!

tbpmusic,
Good idea with the powder. Wife has talk powder and I will try with this after my compression test.
 

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Discussion Starter #6
At first I thought the oil leak was behind the points cover but when I opened it up it was no oil in there:





When I raised my eyes this came in view:




At this point I thought I had found the problem but as I wrote above it still leaks when torqued down.
 

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Good luck with the fix.

Do a search for JohnnyC14 and follow his project log. He's got some great stuff in there that I have referenced frequently.
 

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Znabb said:


At this point I thought I had found the problem but as I wrote above it still leaks when torqued down.
There's really no reason oil should leak from that particular stud.
If the compression checks ok, then try a copper washer on that stud.
If that doesn't work, start looking for a casting flaw or something weird..........

Another thought - that nut is almost directly below the top cam chain roller, which has an o-ring.
Any chance it's leaking there?? I know it's on the other side of the engine, but oil does funny stuff.
 

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I think you'll find the left cylinders head gasket torn into the cam chain galley....., but it could just be "stuck" rings.... either way.... Tear down time.....The "good" cylinder is at minimum spec anyway......
 

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Discussion Starter #12
My problem does sound a lot like a blown head gasket just like MNellis but if I'm lucky and it's only the rings that are stuck on the left cylinder, what can I do to make them "unstuck".
Maybe spray some WD-40 into the cylinder and let it work it's magic over night?

I really would like to run my bike for some more weeks before I tare it to parts.
 

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I would use Marvel Mystery oil, or some similar penetrant, as WD just displaces moisture.... Transmission fluid also could work.... However, you are just postponing the inevitable as the "good" cylinder is ALSO bad (at minimum specs)......IF it is a bad gasket, you could end up burning a channel and ruining the head or cylinders, not to mention that the "fire" leaking past could burn the oil rendering it useless as a lubricant (further damage to cams/tappets, etc).....Please do NOT convince yourself it will/can survive a bit longer....Tear it down before any more destruction occurs.....

I'm not trying to be harsh, and it is surely NOT what you wanted to hear, BUT........
:( :( :eek: Steve
 

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YEP...They ALL are SUPPOSED to be "away" from the spark plug (center of engine)
Unfortunately, that usually means the tappet is trashed...Maybe the camshaft too...Again, sorry to bear bad tidings....
I don't think that alone would cause your low compression, but a stuck (bent) valve could contribute to the problem...
Hard to tell from the pic, but the camshaft does NOT look centered in its seal.... Might be the camera angle...
 

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Discussion Starter #16
Of course I had to get floored by a cold in the middle of my engine investigations.

I have now adjusted the left exhaust valve "the right way around" and it seams like the camshaft and tappet has survived. I have also seald the leaking nut with a copper washer but I am now quite sure that I have a leaking head gasket as you describe 66Sprint.[attachment=2:28romjfz]SSA50133-1024.jpg[/attachment:28romjfz]

I'll be back (said with a slightly German accent) when the top is off (the bikes top that is).


By the way, I bought a rear fender to the bike yesterday as the one on the bike is painted silver. It should be illegal for a 42 year old fender to look this good.
[attachment=1:28romjfz]SSA50161-1024.jpg[/attachment:28romjfz]
Hi all, thumbs upp for this one. :D
[attachment=0:28romjfz]SSA50160-1024.jpg[/attachment:28romjfz]
 

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It is definately illegal for it to look that good... Send it to me and I will properly incarcerate it for this/its horrific crime...... A life sentance bound cruelly to frame rails ought to be appropriate.....LMAO!.... :lol: Steve
 
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