K & N filter & Crankcase breather

[Duncan]

I've got a K & N silver filter which replaces the stock air filter. The stock filter housing has a large crank breather pipe and a small vacuum pipe that goes from the carb then to the air filter housing.

The K & N does not have any way to connect these pipes to it.

The larger crank case breather pipe I'm going to leave connected to the engine so that gases can still escape - but it can't connect to the air filte (don't think this will cause a problem with emissions in the UK) .

The small vacuum carb pipe (previously connected tp the airfilter housing) I'm going to reconnect to my distributor vacuum advance. This is because I have a bosch electronic ignition that currently has a vacuum advance which is not connected and Idon't think there is any other vacuum port on my 34DATR webber carb

Question is will this work?

Regards

Duncan

Carbed 1500 European spec.

 

[Carl_Auer]

The K&N I had

That was on my 78 had a stamped base that gave you a location to cut a hole for a crank vent. It also came with a plastic L hose connector to hook the hose to it. I did not go that route, and went and got a honda tuning crank breather filter for it which worked fine. I had to replace it once in about a year of hard driving in dusty conditions, but I think the filter was like $10 at Pep Boys...

 

[Chris Obert]

The small vacuum carb pipe (previously connected tp the airfilter housing) I'm going to reconnect to my distributor vacuum advance. This is because I have a bosch electronic ignition that currently has a vacuum advance which is not connected and Idon't think there is any other vacuum port on my 34DATR webber carb

Question is will this work?

Regards

Duncan

Carbed 1500 European spec.

I would not connect the PCV valve hose to the vacuum advance on your distributor... You need to connect it to venturi vacuum.

 

[ianlawson]

Engine breather connections to air filter.

.....The small vacuum carb pipe (previously connected tp the airfilter housing) I'm going to reconnect to my distributor vacuum advance..... .

Duncan, the engine breather connections to the air filter body on your UK/Euro-spec 1500 X sound identical to the same system on my Euro-spec 1300 X. The small diameter hose is subjected to manifold (full)vacuum, its purpose is to provide a small degree of vacuum to the air filter body at IDLE, and thus draw engine fumes back into the engine. It should therefore NOT be connected to your vacuum advance on the dissy.
The large diameter breather hose from the engine block up to the air cleaner body performs the same function at engine speeds ABOVE idle. Engine fumes get drawn directly into the carb throat via the internal ducting in the air filter body.
As you are doing away with the OE air filter housing, I would suggest you fit a separate small filter canister to the top of the large breather pipe. These are commonly used by the "boy-racer brigade" when they dispose of the OE air filters on their Jap-crap vehicles.
Regarding the small vacuum hose, I would merely do away with the hose and blank off the vacuum connection at the carb base. Its original function was pretty minimal at best anyway - merely to meet idling emmission requirements when the vehicles were new.

Hope this helps!

cheers, Ian - NZ

 

[Black-Tooth]

Duncan... As Chris says about the vacuum advance...

Go here... a few links below:

http://xwebforums.com/forum/index.php?posts/10512/

Also... If you don't have a bunch of blowby, ducting the crank vent into the intake airstream is a better way of disposing of those fumes than to atmosphere... IMHO. Carl says that well... and I would take the time to do it that way.