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Oil From the Exhaust Ports?

48lesco
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Posts: 721
Joined: Tue Mar 06, 2007 1:45 pm
Location: Olmsted Twp, Ohio

Post by 48lesco » Wed Sep 26, 2012 8:25 am

Sounds like the breather may be plugged. Assuming you have the later style on the head cap, there should be a nipple there with a rubber tube. Make sure its open and can flow freely. I would just gently blow into it to see if its blocked. Don't use compressed air because if there is something jamming it up you don't want to blow it into your head. And most importantly - remove the dipstick before you do this to vent the crankcase.

On the Dream engine, the pistons go up and down together and pressurize the crankcase. This can force oil down the valve guides into the exhaust port. Valve guides being the only possibility I can think of besides a crack that could put oil where you're saying. Maybe post a picture to make sure we're all on the same page.
-48

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

Post by houseowax » Wed Sep 26, 2012 8:45 am

Yes, I definitely installed the o-rings over the knock pins and they were brand new. I thought of that first but I'm 110% sure I did that.
'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 » Wed Sep 26, 2012 9:47 am

I will post pics later- the bike and I are in different places today. Maybe I'll even post a video so you can really see the volume of oil.

Two things that I'm thinking of, although neither seem really relevant:

A) As the sump was completely dry, I went by Silver's recommendation and added about 2 quarts of oil- more than is usually required. That doesn't seem like it could cause this, though.

B) There's a point in Silver's reassembly guide that states "... install the top cylinder head cover gasket, the breather shield plate and gasket (not used in '61) with drain holes DOWN and finally the top cylinder head cover"
I made sure that my gaskets were installed without obviously obstructing any holes and I checked wherever possible against the engine diagrams, but I was unsure of what these 'drain holes' were. Could I have missed something there that might produce this mess?
'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 » Wed Sep 26, 2012 3:10 pm

As you might be able to tell, I have been dwelling on this problem all day.

One more thing- I replaced the rings. I'm sure they were the right rings and they all sat nicely in their grooves. I staggered the ring gaps at approx 10:00, 2:00 and 6:00 and although the punch marks were nearly invisible I'm almost completely certain that they were all installed with the proper side up.

Still, suppose I did one of those steps incorrectly- could THAT produce an oil gush like the one I described?
'63 CA77 - Giving me all kinds of headaches.
'64 CA77 - Patiently waiting it's turn
'65 CB77 - A 'great winter project'

48lesco
honda305.com Member
Posts: 721
Joined: Tue Mar 06, 2007 1:45 pm
Location: Olmsted Twp, Ohio

Post by 48lesco » Wed Sep 26, 2012 3:18 pm

breather?

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

Post by houseowax » Wed Sep 26, 2012 3:26 pm

48lesco- I'm away from the bike today so I can't check, but it's on my 'high priority' list. I'll give it a shot tomorrow. I'm casting my nets as wide as possible so I have some backup ideas if that one isn't it. As I'm sure to mention in almost every post, I'm new to this and I'm learning as I go so I'm ill-equipped to diagnose these things. I thought I had a clear understanding of the valves and the timing but now it's dawning on me that maybe I'm not as clear on it as I might've thought.

Anyhow, thanks for the idea. I'll report back here as soon as I have anything to report.
'63 CA77 - Giving me all kinds of headaches.
'64 CA77 - Patiently waiting it's turn
'65 CB77 - A 'great winter project'

48lesco
honda305.com Member
Posts: 721
Joined: Tue Mar 06, 2007 1:45 pm
Location: Olmsted Twp, Ohio

Post by 48lesco » Wed Sep 26, 2012 3:34 pm

If the motor ran and idled for some time before the geyser, the valve timing is probably OK. Piston ring orientation shouldn't cause the problem you describe. Post some pics and a video if you can. Don't get discouraged, we'll figure it out!

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