PD: Primary Drive Alton Generator

erik

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VOC Member
How should I seal the gap betwenn the Primary drive and the alton Generator on a twin? regards Erik
 

timetraveller

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With the Walkernators, if oil is used in the primary drive, I provide a piece of soft 'rubber' round section material which has to be cut to length and the ends superglued together to make a large soft 'o'ring. If the bike is used with ATF in the primary drive then I provide a similar length of silicon rubber tubing which has to be cut to length and then have the ends glued together with clear silicon sealant. The reason for this is that the dynamo side of the casting can vary from having a cast in cone shape, a machined cone shape or a flat face. That means that I cannot provide a large 'o' ring that would suite everyone. If you cannot find what you want I could send you a small length of either type of material.
 

Dave61

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With the Walkernators, if oil is used in the primary drive, I provide a piece of soft 'rubber' round section material which has to be cut to length and the ends superglued together to make a large soft 'o'ring. If the bike is used with ATF in the primary drive then I provide a similar length of silicon rubber tubing which has to be cut to length and then have the ends glued together with clear silicon sealant. The reason for this is that the dynamo side of the casting can vary from having a cast in cone shape, a machined cone shape or a flat face. That means that I cannot provide a large 'o' ring that would suite everyone. If you cannot find what you want I could send you a small length of either type of material.
Hi Norman,
Just wanted to ask, isn't there a school of thought that the Primary breathes through the dynamo ?
Mine has the cast in cone shape & the soft rubber tube,(to suit engine oil), you sent me with the Walkernator doesn't take up the clearance so I was contemplating running without it sealed, am I being a total idiot ?
Cheers
Dave
 

Bill Thomas

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My ex l/ning, Has a ton of oil coming out the gap with a Macdouglator, Bruce sent me some special soft stuff that I still have to try. Cheers Bill.
 

timetraveller

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Hi Dave, my experience is that if one does not seal it then it blows oil out This is with the oil thrower etc all installed. There is another school of thought which is that there has to be a gap there to let the primary chain case breath. One of my bikes has a banjo connection on the oil filler cap on the primary cover so there is no pressure in there
 

erik

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what about using Silicone sealer and Drilling a small hole in a remote place where no oil is thrown to by the chain?
 

Gary Gittleson

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I've been running mine lately with just the oil thrower (on an Alton) and a bit less oil in the primary; just enough to cover the bottom run of the chain. Nothing seems to be coming out of there. I should add that I have a D, with the breather on one valve cover. I put that over the front intake valve, connected to a one-way valve and hose leading down to the bottom and out the back. The end of the hose is always dry. The previous owner had drilled and tapped the magneto inspection cover and placed a one-way hydraulic vale there with a little tube pointing downward. I left it because it seemed quaint. So I have two one-way breathers. I was also experiencing some oil blowing out of the oil tank cap. I made a diverter for the return but it didn't help. I assumed it was caused by pressure buildup in the tank. So I drilled and tapped the rear cylinder exhaust valve cap to accept a small brass pipe and connected that to a hose going the chain oiler outlet to allow the pressure to pass to the engine and be consumed by the one-way breathers. Whatever oil is also delivered over the valve drops down into the engine. This seems to have worked. My bike is a "D" Rapide, so the tank is on the side. Neither of the breather valve covers is visible without very careful inspection under the fuel tank and the hoses are tucked away pretty well.

After several thousand miles in this configuration, everything is quite dry. It does leave a spot of oil after resting for a few days, no bigger than an inch in diameter, coming from under the gearchange cover. I haven't tracked that one down yet. The valve lifter cable area is dry.
 

stu spalding

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The flange ET164 and oil thrower PD28 are there to provide a breather for the chaincase. If a lot of oil is being blown past the dynamo drive it means that there is something very wrong with the seal, whichever is used, on the primary side mains bearings. Trying to cure blowby using sealants or whatever usually results in an oily clutch when the chaincase becomes pressurised. The only cure is to address the problem at source and prevent the crankcase breathing through the main bearings. Cheers, Stu.
 

Dave61

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Non-VOC Member
Hi Dave, my experience is that if one does not seal it then it blows oil out This is with the oil thrower etc all installed. There is another school of thought which is that there has to be a gap there to let the primary chain case breath. One of my bikes has a banjo connection on the oil filler cap on the primary cover so there is no pressure in there
Thanks for that Norman, I`ll have a rethink.
Cheers
Dave
 

Sakura

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Non-VOC Member
To reduce slight oil mist around the dynamo, I made a breather in the inspection cap. I marked the flat at the top when the cap is tight. Removed the cap and drilled a 0.125" hole in the marked flat. Threaded the inside of the cap. Inserted a threaded ring first, then a very fine mesh, secured by another threaded ring. The mesh seems to stop most of the oil as a sort of baffle. When I check the chain tension I drain the cap of what little oil collects. Seems to work.
 
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