Holland Norton Works Breather

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NoLongerHere

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I thought I'd have a look at this XS breather I've had fitted to.my Commando for a couple of years in an effort to try and site it closer to the engine rather than the tank as I noticed a milky colour oil residue at the oil tank end.
When I first fitted it I thought it would only let air out and not back in but it appears to now let air in and out, not freely one way I admit.
Another type of breather I have to hand only lets air travel one way.
Holland Norton Works Breather
I've had the pictured one apart and nothing looks obviously faulty.
Is it still working properly though?
 
Not if its not a one way valve, it does need to stop air getting back in to be 100% effective, has someone drilled a small hole for the oil to drain back into as that will remove the 100%.
 
Not if its not a one way valve, it does need to stop air getting back in to be 100% effective, has someone drilled a small hole for the oil to drain back into as that will remove the 100%.

No hole, I bought it new and fitted it.
I did seem to remember it was only letting air travel one way but not 100% sure with my memory
Might just be worn out then?
 
Its worn out if there is no hole. They are ERG valves for small motorcycle engines, just go into ebay then motorcycle parts and search for 'EGR valve' , plenty will come up.
 
Its worn out if there is no hole. They are ERG valves for small motorcycle engines, just go into ebay then motorcycle parts and search for 'EGR valve' , plenty will come up.

I'll fit the one I have already to hand then, it's made in Germany so should be ok.
I think I was told it was a Renault (Yes I know that's French) part.

Thanks for the replies all.
 
Not if its not a one way valve, it does need to stop air getting back in to be 100% effective, has someone drilled a small hole for the oil to drain back into as that will remove the 100%.

It’s ok to have a small hole for oil drain back if you want. I don’t think it’s totally necessary. I did drill a hole. If the hole is small enough it won’t have any impact on the breathing. The small hole doesn’t support enough volume to be material.
 
I run my breather hose into a 1 ltr plastic catch bottle after the RV and in 12 months very little oil in it, so really no need for a small hole in the RV, the breather hose goes to the bottom of the catch bottle and up the top of the bottle has a hole for the air to escape, I don't run it to my oil tank.

Ashley
 
I have one of these HNW breathers, it had a drain hole from new, and yes it breathes freely one way but only a little the other.
 
Hi,

Our current offered ‘PCV engine breather valve #H14’ doesn’t have a safety hole (indeed we did offer a breather valve with a tiny safety hole inside). Like Swooshdave also mentioned it isn’t totally necessary but to be sure no oil-mix will block the reed valve you can drill a 1,5mm hole next to the reed valve in the removable inside plate. The safety hole doesn't affect the functioning. With a safety hole the breather valve should breath freely one way and only a little the other. Without a safety hole the breather valve should breath only one way.

Constant
www.hollandnortonworks.eu
 
Hi,

Our current offered ‘PCV engine breather valve #H14’ doesn’t have a safety hole (indeed we did offer a breather valve with a tiny safety hole inside). Like Swooshdave also mentioned it isn’t totally necessary but to be sure no oil-mix will block the reed valve you can drill a 1,5mm hole next to the reed valve in the removable inside plate. The safety hole doesn't affect the functioning. With a safety hole the breather valve should breath freely one way and only a little the other. Without a safety hole the breather valve should breath only one way.

Constant
www.hollandnortonworks.eu

Grotjes Constant, so it does have a hole in then in which case this might still be working as intended.
Holland Norton Works Breather
 
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Reed valves are dead simple devices and not prone to failure, at least not how we use them.

Best to retest and let us know.

I think the answer is, it's got the drain hole in from when it was supplied and therefore isn't a 100% one way breather. Not knowing it had the drain hole I wrongly thought it was hence the original post as I thought something had happened to it.
Anyway, it's on a shelf now as it's been replaced with one that is.
 
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Hi I have the Holland breather but not sure how to fit(it does have a drain hole) . However, the Help Doman Motomite 80190 power brake vacuum check valve seems to be a useful item. People have fitted and it and say its work well. Its very hard to find in the UK . I went on Amazon UK and it ranges in price from 21 pounds sterling to 30 pounds. I then went on the USA Amazon site and including shipping to the UK is around $7to $8 dollars US(around£5 ) I ordered one! Once I have replaced the timing chain on my late 72 non combat 750 I will fit and let you know how it goes. I shall probably just fit it to the big plastic pipe going from my large tower breather on the timing chest. I like the Colorado Works item but its $220 dollars US. This info might help folk.
 
Expect to replace the Motomite valve every year or two. But at that price, who cares. My experience was that I still had positive
crankcase pressure, though probably less than with nothing fitted, as evidenced by the usual oil leaks. I have the Comstock Engineering
sump reed valve as sold by cNw which, as an added benefit, very quickly purges any oil in the sump on starting the motor. It truly stopped
all oil leaks.
 
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