Out cutting firewood with 1984 Husky 50 Rancher and noticed a lot of bar oil dribbles on the cut sections. Lot of oil coming out of the hole above the bar oil filler cap in the photo.
Obviously a vent plug has fallen out. Is this a part which is common to old Huskys and any chance I might be able to get one these days?
I had a quick look online to see what sort of plug is in that position but don't know if that part is available anymore ,I'd probably just block it off with a wood dowel or small welch plug or file up a plug as it looks like a rubber blank plug but if it's a breather you'd try putting in a breather.
Ok you guys are correct it's a breather plug , must let air into the oil tank so you get correct oil flow ,the duckbill valve works on pressure not suction you may need a vacuum valve,you may be able to adapt a valve from another saw or do as Tyler suggested with the fuel line with a vac valve..
I see some Duckbill valves are listed for fuel and oil but must be incorrectly listed and will only vent fuel tank pressure ,when looking at all the stihl chainsaw parts lists all the duckbill valves are for fuel vents even though some sellers list them for a chainsaw oil vent.
I thought they would work the same as the duck bill prevents cavitation of the fuel tank as well by letting air in so it doesnt vapour lock. That long since I worked on one with a easily removable duckbill i cant remember.
It wouldnt let air out as when the engine is running and fuel shaken up (pressure) it would jet out the cap if you turned it over
Different chainsaws use different breathers but the principle is the same ,with the fuel tank on a chainsaw as you say there must be a breather to let air in to stop vapour lock ,the duckbill can't do this as it can't work as a vacuum check valve ,in the image below the tank breather that lets air into the tank would be 18, then you have the duckbill valve 25 to let fuel tank pressure out ,I would think fuel doesn't spray everywhere when pressure is relieved out the duckbill because they also use a filter in the duckbill , the foam filter works by stopping fuel spewing out .
As we know If you don't have a pressure relief on a chainsaw fuel tank ,you would open the fuel cap and get sprayed in the face with fuel after a little pressure built up .
The reason that there are a few people advertising the duckbill for an oil tank breather I think is because the oil tank and fuel tank on some chainsaws are one part with 2 tanks built in so they say it's for fuel & oil tank but just used on the fuel side.
I've never seen chainsaw tank breathers discussed before but just couldn't see how a duckbill could be used for a vac valve but if I've missed something happy to be corrected.
Couldn't find the part needed. The rest of the saw is in good shape, motor starts and runs very nicely and has plenty of power for it's size so rather than toss it into a corner of the shed I have gone back to the old daze - filled a squeeze bottle with bar oil and giving the bar and chain a squirt now and then while cutting.
One of my early saws was a small McCulloch which had a manual oiler.
It might be worth grabbing a bike schrader valve (later model valve ) and use that as a vac valve ,I tried one by removing a few coils on the spring then stretching the spring, it opened with little vacuum and closed under spring pressure, not sure how long it will last in oil but you can grab a Schrader valve from a car air conditioner system as that shouldn't have a problem with oil.
If only Max :-) Problem is the original fitted into a shallow round recess and was flush with the surface of the case. I suspect it was integral with the rubber vent tube but had fractured off with age and fallen out.
I tried punching small discs from neoprene with pinholes, and foam, also stuck tape with a pinhole over the recess but due to the location on the front of the case and the fact I'm out there gathering firewood from trees and branches which have fallen into dense saplings and undergrowth any contact with a twig knocked out my repair.
In the unlikely event this saw gets to be dismantled maybe the hole can be blanked off and a new vent made internally. I have nine other rescued and running saws plus several awaiting rescue so will just carry on with manual oiling this Rancher until some other part expires.
In the meantime I got an old McCulloch CS 370 going with minimal effort and it is doing a great job as a 14 incher.
I thought that may be the case MM ,if the saw had a shallow round recess ,I guess you could easily block the hole with a cork or round dowel ,even if you had to make one by putting a small bit of wood in a drill chuck and spinning it against a pedestal grinding wheel.Probably quite a few other ways to block the oil leak too.
I would just drill a hole in the oil cap after the oil leak is blocked and use a valve stem from a motor bike tube as it has a longer thread then just use 2 lock nuts ,one on each side of the oil cap ,on the outside of the cap you wouldn't need much of the valve stem sticking out ,also I would drill a hole in a valve cap end and put a tiny sponge inside the valve cap and that will stop any dirt getting stuck in the valve..
Up to you though if you could be bothered ,I just know if it was me stopping all the time while cutting and using an oil can would drive me crazy .
Max, when younger my firewood gathering was done with an axe and bow saw, trust me giving the bar/chain a quick squirt of bar oil between cuts is not a problem :-)
