Dangermouse449
Husqvarna
Pro Class
Like most guys on here, I've had the occasional bout of oil in my air filter from the engine breather and it has happened to me the last few times I've ridden.
I also want to acknowledge right here from the start, that there is an easy, well made & well priced fix for this available from one of the CH site sponsors in the Zip-ty breather.
However, I've been looking at my engine recently & wanted to see if there was something I could do myself. This is what I came up with.
I've been out today with 2 of my good riding mates today & we did some of our more advanced stuff, dropped the bike a couple of times, ran out of talent on steep hills, revved it hard on the long straights & very happy to say there is not a drop of oil in the air-filter at days end. Sweet.
I noticed this plug in the RH side of the head between the 2 cam-cover half-moons and had the thought, if I tapped a thread into the hole & fitted an elbow, the engine could breathe up past the cam-chain & on up to the air-cleaner as it should.
This is how I went about it.
First, pull the head cover.

Next, place a finger full of grease in the hole behind the plug to catch any drillings.
Carefully drill a hole through the center of the plug to suit a thread tap, mine was a 6mm tap as I had a long 6mm bolt to suit. Tap the thread all the way through.
** Be especially careful NOT to let any fillings get past your grease into the engine**

Choose a bolt with a little length in it & use it to 'jack' the plug out. (It is just glued in place with Loctite).
I used my long bolt, a socket that cleared the plug & a washer.

I purchased a 1/4 BSP thread 90deg elbow with a barbed end to suit 1/2 hose from a local auto parts store. I already had a 1/4 BSP thread tap which was a good fit for the hole without drilling.
Again, use grease to catch any shavings & be careful not to jack the tap into the inlet cam sprocket which is close to the back of the hole.
Put some sealer on the thread & screw in the fitting.
I was able to fit the factory breather hose, uncut, to the fitting & had a slight rise in the hose all the way to the air-cleaner.

While a the parts store, I got a 1/2 emission rated sealing plug & fitted it to the factory transmission breather to block it off.
Total time was about 2 hrs all up & running again.
I also want to acknowledge right here from the start, that there is an easy, well made & well priced fix for this available from one of the CH site sponsors in the Zip-ty breather.
However, I've been looking at my engine recently & wanted to see if there was something I could do myself. This is what I came up with.
I've been out today with 2 of my good riding mates today & we did some of our more advanced stuff, dropped the bike a couple of times, ran out of talent on steep hills, revved it hard on the long straights & very happy to say there is not a drop of oil in the air-filter at days end. Sweet.

I noticed this plug in the RH side of the head between the 2 cam-cover half-moons and had the thought, if I tapped a thread into the hole & fitted an elbow, the engine could breathe up past the cam-chain & on up to the air-cleaner as it should.
This is how I went about it.
First, pull the head cover.

Next, place a finger full of grease in the hole behind the plug to catch any drillings.
Carefully drill a hole through the center of the plug to suit a thread tap, mine was a 6mm tap as I had a long 6mm bolt to suit. Tap the thread all the way through.
** Be especially careful NOT to let any fillings get past your grease into the engine**

Choose a bolt with a little length in it & use it to 'jack' the plug out. (It is just glued in place with Loctite).
I used my long bolt, a socket that cleared the plug & a washer.

I purchased a 1/4 BSP thread 90deg elbow with a barbed end to suit 1/2 hose from a local auto parts store. I already had a 1/4 BSP thread tap which was a good fit for the hole without drilling.
Again, use grease to catch any shavings & be careful not to jack the tap into the inlet cam sprocket which is close to the back of the hole.
Put some sealer on the thread & screw in the fitting.
I was able to fit the factory breather hose, uncut, to the fitting & had a slight rise in the hose all the way to the air-cleaner.

While a the parts store, I got a 1/2 emission rated sealing plug & fitted it to the factory transmission breather to block it off.
Total time was about 2 hrs all up & running again.
