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Oil From the Exhaust Ports?

houseowax
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Posts: 198
Joined: Thu Nov 19, 2009 9:41 am
Location: Brooklyn, NY

Post by houseowax » Thu Sep 27, 2012 5:58 pm

My money is on the nuts that join the two halves of the head. I'll give it a go tomorrow and see what happens and report back. Thanks everyone- Steve

EDIT: Just talked to a friend who was by to see the bike. He claimed that the stud that's on the jugs is broken! $#@&%!!! I Just had those cylinders honed!
As far as I can tell that stud is cast into the cylinder head, right? It's not repairable?
'63 CA77 - Giving me all kinds of headaches.
'64 CA77 - Patiently waiting it's turn
'65 CB77 - A 'great winter project'

CliffC
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Location: Roseburg, Oregon

Post by CliffC » Fri Sep 28, 2012 1:00 am

Steve,
The studs are threaded into the upper engine case. To determine if one or more are broken you should be able to move them at the top of the head. If they are stripped you should be able to turn them either way with little resistance. If they are stripped or broken they can be fixed but you will have to pull head and cylinders. Even if they are stripped or broke, I still cannot see why all that oil is coming out of the exhaust ports. Keep us posted on what you find. Cliff

48lesco
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Location: Olmsted Twp, Ohio

Post by 48lesco » Fri Sep 28, 2012 7:20 am

Breather????

It would be hard to "break" one of those studs. Are the threads stripped? If the studs weren't installed in the first place and the threads in the cylinder block are OK you can just put 6mm hex bolts in without pulling the engine.

Are the studs broken/missing on both sides?

Is the leak the same on both sides?

+1 on Oldstan's idea - New gaskets on the side covers?

Check page 21 of the Silver "Restoration Reference Guide" for info on the oil seepage issue.

houseowax
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Posts: 198
Joined: Thu Nov 19, 2009 9:41 am
Location: Brooklyn, NY

Post by houseowax » Fri Sep 28, 2012 9:00 am

STILL haven't been in to see the bike, but to clarify - the stud that is broken isn't one of the 8 long ones that hold the head to the crankcase. Rather it's one of the small ones that join the two halves of the head, right to the side of the head gasket/spark plug holes. See attached pic.
I'll know better when I get there and I'll report back. I think I have one to spare on my donor engine, but I imagine getting it out isn't going to be pretty. I spoke to LM yesterday and he offered up some advice so hopefully my lucky stars will be aligned and this'll be an easy fix

Thanks, everyone - I'll be back with a report ASAP
Attachments
the stud in question.
the stud in question.
'63 CA77 - Giving me all kinds of headaches.
'64 CA77 - Patiently waiting it's turn
'65 CB77 - A 'great winter project'

houseowax
honda305.com Member
Posts: 198
Joined: Thu Nov 19, 2009 9:41 am
Location: Brooklyn, NY

Post by houseowax » Fri Sep 28, 2012 4:21 pm

I owe you all an apology- I need to clean up my act and be more attentive.
The oil wasn't leaking from the exhaust OR the spark plugs.

So I replaced the broken stud, but once in front of the engine it occurred to me that with the head bolts torqued to 22ft lbs THAT couldn't really be the issue. Got the engine back in with the copper exhaust gaskets in place ( again, obviously not relevant once I'm in front of the engine).
I get it started up and it sounds great and not a drop of oil...for about 10 seconds., Then a gush of oil from the same place as always. But instead of panicking I let it run and watched carefully and I discerned that it was in fact originating from the left side cylinder head cover.

So I took that off and had a look. DEFINITELY the source. I tightened up the nut on the cam locking bolt because that's all I could think of and it was a mite loose. Turned it over with the same result- free flowing oil. The packing is in place and it's a new one.

As a last effort, i left the side cover off and started it up. The oil SHOT out of the opening in the rocker pin in a stream!
When I think of it I understand that the oil travels up the outermost stud on the exhaust side of the engine. The rocker pins have recesses to allow for the studs to pass through. What SHOULD keep the oil from passing through the rocker pin and into the side cover? Certainly it has to be more than that flimsy gasket?

Anyhow, I apologize to everyone who tried to help me find an answer to my question when I was incorrectly identifying the problem. I promise to be more careful and observant in the future. Thanks everyone.- Steve
'63 CA77 - Giving me all kinds of headaches.
'64 CA77 - Patiently waiting it's turn
'65 CB77 - A 'great winter project'

OldStan
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Location: Galt, California

Post by OldStan » Fri Sep 28, 2012 4:32 pm

If you had the head apart, you might not have the cam bearing seated in far enough and holding the cover out slightly. All that seals it is the gasket. It's not a high pressure system.
63 CA78

houseowax
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Posts: 198
Joined: Thu Nov 19, 2009 9:41 am
Location: Brooklyn, NY

Post by houseowax » Sat Sep 29, 2012 9:52 am

I'll triple check- I know the Silver manual spent a great deal of time stressing this issue and I thought I had a satisfactory seating on my side covers, but I'm really kinda stumped as to how it could be anything else.

If I loosen the screw and put a wooden block on the end of the cam bolt and tap it with a deadblow hammer that oughta be sufficient, right? I was VERY careful to install the bearings flush so I feel pretty good about that aspect of the assembly.
'63 CA77 - Giving me all kinds of headaches.
'64 CA77 - Patiently waiting it's turn
'65 CB77 - A 'great winter project'

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