L-Series Valve Cover Breather Tube

[serum114]

I'm going to get a valve cover powder coated and I was wondering about the discrepancy I've seen in the direction L-series breather tubes are pointing.

My question is; is the direction adjustable? ( It's now pointing towards the back passenger side of the car and I would like it pointing towards the carburetor)

Also what is the material used when fitting the breather in place?

 

[Draker]

Paging jrock.

[serum114]

Does Jrock have the answers or am I in for a berating?  :geek:

[Draker]

I've heard it's just a pressed in fitting with some glue. jrock powder coats for a living.. I figured he would know.

[datsunhead]

Its tapered pipe thread but also glued To make sure you break it trying to get it out. Lol You can get it out just be careful.

[serum114]

So it's a twist not a pull to to remove it?

Does anyone know what glue to use?

[Ratwagon1600]

So it's a twist not a pull to to remove it?

Does anyone know what glue to use?

RW has used a two part epoxy called Araldite.

 

http://www.selleys.com.au/adhesives/household-adhesive/araldite/

 

Not sure where/if you can get it in Murica, but, any epoxy type bonding agent should work.

 

Just remember to follow manufacturers reccomendations re curing times.

[Stoffregen Motorsports]

Heat should help you get it out. Any silicon will seal it but if you want it to hold properly, you need to use an epoxy of some kind. JB weld should work.

 

However...if you're going to powder coat the assembly, the heat of the powder coating might melt or otherwise distort/ruin the epoxy. I would either have the assembly coated with no epoxy or have them coated in two pieces then put them together after the coating has cured.

[serum114]

Heat should help you get it out. Any silicon will seal it but if you want it to hold properly, you need to use an epoxy of some kind. JB weld should work.

 

However...if you're going to powder coat the assembly, the heat of the powder coating might melt or otherwise distort/ruin the epoxy. I would either have the assembly coated with no epoxy or have them coated in two pieces then put them together after the coating has cured.

 

 

I think I will do that and have the two pieces powder coated separately.

 

Does anyone know if there will be a problem with changing the direction the tube is facing?

The more I've looked, the "NISSAN OHC" badged valve covers (the one I'm using) seem to all have the breather pointing the same direction, towards the passenger seat...

 

Also has anyone seen the breather tube removed completely and a filter installed directly to the top of the valve cover?

[Lockleaf]

Direction it faces shouldn't matter at all. Bigtanker shaved it off the top of his and built a custom breather out the back of the valve cover.

[wayno]

It's a threaded hole, you can point it any direction you like, you just screw it in until it starts getting tight, and then stop where you want it pointed.

I don't even use a glue, but plumbers pipe tape might help seal it if you have any leaks around the base.

Some folks on here put little filters on it, but I would pipe it to the airfilter, and let any fumes go into/down the carb.

[datzenmike]

Also has anyone seen the breather tube removed completely and a filter installed directly to the top of the valve cover?

 

That would be very ill advised. The name 'breather tube' should give you pause.

 

The breather tube allows filtered air into the engine to make up what is drawn out by the PCV  system. Under heavy load the PCV system can become overwhelmed and excess blow by has to go somewhere. The air reverses direction and blows back into the air filter housing and is sucked into the carburetor. Without the valve cover breather, the engine crankcase would pressurize and push oil out the seals and gaskets.

[serum114]

That would be very ill advised. The name 'breather tube' should give you pause.

 

The breather tube allows filtered air into the engine to make up what is drawn out by the PCV  system. Under heavy load the PCV system can become overwhelmed and excess blow by has to go somewhere. The air reverses direction and blows back into the air filter housing and is sucked into the carburetor. Without the valve cover breather, the engine crankcase would pressurize and push oil out the seals and gaskets.

 

My valve cover has the small breather/filter attached to the breather tube. I was thinking about removing the tube but leave the small breather/filter attached to the valve cover where the elbow connecting tube threads in. Maybe thread a small straight pipe fitting in that spot and attach the breather/filter to that? Should work the same as with the elbow in place right?

[Stoffregen Motorsports]

Unless you're pulling a vacuum with something like a dry sump oil pump, you should not remove breathers from the engine or you will run into leaky oil seals, possibly blown out seals.

 

I used to vent them to atmosphere, but after some playing around with it, I found that you could simply plumb it into the air cleaner and pull a small vacuum so it's not a leaky mess. The you don't need to run the PCV system. But if you want the PCV system in tact, then you definitely want that breather.