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Would that also cause excessive oil consumption? Thanks
Exhaust Valve Guide Seal Question
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marshg246
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Jim, have you ever seen a street Norton with decent exhaust valves and guides burn oil continuously due to the lack of exhaust seals. If so, can you explain how it is possible?For a guide without a groove you need a metal ring on the bottom of the seal to keep it from coming off. You also need a spring or ring at the top for a good seal to maintain tension. This combo is not always easy to find. Check the ID of the seal before installing. If they are too loose on the valve stem they will leak oil. Different brand seals may look the same but some don't have enough tension on the valve stem.
Also, other than occasionally coming off, have you ever seen a street Norton engine burning oil continuously using the standard Norton intake guide seals that are not worn out and with the rocker spindles installed correctly? If so, please explain why as I never had the problem.
Fast Eddie
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I currently run two Steve Maney heads. Neither of them have seals on inlet or exhaust. Neither of them burn oil. However both have a larger central oil drain (std mod on the stage 3 heads).
So, in my experience at least, a Norton with a clear drain and good fitting valves / guides does not suck oil down the guides. And I fail to see why one should?
Yes, modern auto engines have seals, but they have much greater oil flow to their DOHC heads, run thin oil, have catalytic converters to protect and have very extended service intervals (in fact the target is ‘sealed for life’ engines).
So, in my experience at least, a Norton with a clear drain and good fitting valves / guides does not suck oil down the guides. And I fail to see why one should?
Yes, modern auto engines have seals, but they have much greater oil flow to their DOHC heads, run thin oil, have catalytic converters to protect and have very extended service intervals (in fact the target is ‘sealed for life’ engines).
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If I had a motorcycle engine which was burning oil, the last place I would look is the valve guides. If the valves stems are so sloppy in the guides to allow that much oil to pass ? - It has to be rings - or a shagged big end allowing too much oil to pass, and flooding the cases.
baz
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Tell that to a honda cb550 I used to own
It smoked like a pig when two ehasust valve guides were worn
Once replaced it was fine
marshg246
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Left idling on the side stand ensure that there is a great deal of oid in the intake area, especially on the drive side. IMHO, terrible for a Norton to be left idling and double terrible on the side stand!
Thanks I no you are right just to lazy to shut it of to open my gates , must try harder
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James , I put my head every time it's pulled straight into my GTA Gord Bush , trusted machine shop , familiar with Norton / Btitbikes work . I don't try to figure out things myself . Last headwork was new guides ( exhaust ) and a booth clean up . New valves too . New J.S. seals , not Norton . In my experience of 4 Nortons it's always the head . Not piston wear . Enjoy .
cliffa
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Have you already checked that the oil drain is clear all the way?
marshg246
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Did you check the one oil drain in the intake side, not just in the head but in the cylinders all the way to the timing chest. Put oil in the hole at the top of the cylinder and see if it drains away.
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Your problem may not be the fault of lack of oil seals on the exhaust. My post was to show you which oil seals I prefer. I prefer a clean burning Norton with seals all around. I also prefer total seal rings. I want the oil to stay out of the combustion chamber and it only takes a little more care to insure that.
cliffa
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Have you seen this parallel thread?, it may be relevant.
Uh-oh!
Never fear, I’ll be tightening the head and exhaust as needed. I got those nylon/rubber gaskets that are reusable and don’t tear when taking rocker covers off. Nice to have when checking valve clearances which I’ll do after retightening the head. Curious to see how much a change in clearances...
www.accessnorton.com
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Larry S
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Yes, I am the knuckle head in question. Lol!Have you seen this parallel thread, it may be relevant.
Uh-oh!
Never fear, I’ll be tightening the head and exhaust as needed. I got those nylon/rubber gaskets that are reusable and don’t tear when taking rocker covers off. Nice to have when checking valve clearances which I’ll do after retightening the head. Curious to see how much a change in clearances...
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Your post about gapless rings interested me. If there was a performance boost it was most likely due to better fit of the rings in the bore, - Might also be relevant to excessive oil burning. When you compress a piston ring, you might assume that each part of the ring bends the same amount. There might be points at which the rings apply less pressure against the cylinder wall. The gapless rings might be manufactured by a better process, than normal.
The old rings in a worn motor might give better sealing than new rings in a worn motor.
Britstuff
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No problem with the inlet drain hole as far as I can see.
Jim, Thank you for your comments. I'm thinking I may want to go with your valve seals, pistons and total seal rings. Would certainly be a nice upgrade. I will be in touch.
Hmmm, yes, the "Uh-Oh" thread is very interesting. I am hoping to pull the barrel on my Commando tomorrow. I will pay close attention to if a ring or two are upside down. That would certainly explain my problem.
Cheers,
James
Jim, Thank you for your comments. I'm thinking I may want to go with your valve seals, pistons and total seal rings. Would certainly be a nice upgrade. I will be in touch.
Hmmm, yes, the "Uh-Oh" thread is very interesting. I am hoping to pull the barrel on my Commando tomorrow. I will pay close attention to if a ring or two are upside down. That would certainly explain my problem.
Cheers,
James
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marshg246
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A few years ago I had a discussion with a Hastings engineer. Here are the hi-points.
The oil ring is not there to prevent oil from getting to the combustion chamber, it is there to control the amount of oil left on the cylinder walls for the compression rings.
The middle compression ring (at least) has a bevel on the inside. The ring will remove most of the rest of the oil if installed correctly or will force the oil up to the top ring if upside down. Of course, it also helps with compression.
The top ring also slightly controls the oil but is the main ring for compression. No oil should get past it and the incredibly thin layer of oil left by the properly installed middle ring is all the top ring needs. If it is upside down it will pump a little oil into the combustion chamber and not seal as well as it should. If both compression rings are upside down, almost all of the cylinder wall lubrication will be pumped into the combustion chamber.
He was discussing rings like those they used to make for Norton. This in no way says that all rings use the same technology/thinking!
The oil ring is not there to prevent oil from getting to the combustion chamber, it is there to control the amount of oil left on the cylinder walls for the compression rings.
The middle compression ring (at least) has a bevel on the inside. The ring will remove most of the rest of the oil if installed correctly or will force the oil up to the top ring if upside down. Of course, it also helps with compression.
The top ring also slightly controls the oil but is the main ring for compression. No oil should get past it and the incredibly thin layer of oil left by the properly installed middle ring is all the top ring needs. If it is upside down it will pump a little oil into the combustion chamber and not seal as well as it should. If both compression rings are upside down, almost all of the cylinder wall lubrication will be pumped into the combustion chamber.
He was discussing rings like those they used to make for Norton. This in no way says that all rings use the same technology/thinking!
cliffa
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He, who never made a mistake, never learned anything.
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