LINEAWEAVER

Hello friends,
For what it may be worth:

If one can insure a slight crankcase vacuum (in particularly regarding a large displacement single) power shall increase coupled with a reduction in oil spewing. Such technology is certainly not new as it has been used by the drag racing community for many, many years. Simply look to the nineteen sixties era blown altereds with their exhaust scavenged crankcases.

On many a fours cycle engine (including Harley Davidson Big Twins and Rotax Singles) I have placed a high speed one-way check valve in the crankcase vent line. Doing such has proven true to form for some two decades now. (As a matter of fact their are over the counter CNC pieces now available through most HD speed merchants.)

Regarding the Husaberg engine:
Power output did not improve using such a device primarily as a result of the OEM crankcase reed valve. However, If a reduction of oil spewing is your primary objective an auxiliary check valve could be just what the doctor ordered.

An automotive air pump check valve serves the purpose nicely @ a fraction of the HD cost. One may purchase KEM part number 174-176 or cross reference said number to that of your local automotive vendors inventory (Kragen, etc.) .

Hope this helps.

Sincerely,
Dale

husabutt

Dale thanks for the part number. Is the reason Husaberg routes the breather to the air intake an emissions issue or to possibly help pull the pressure from the crankcase? or maybe not to waste good Delo 400

Thanks,

Eric

wildbill

Question:Are you referring to a PVC valve?If that is what it is;then that would make things a lot easier.Thanks for the information.

LINEAWEAVER

Hi Bill,
No, it is not a Positive Crankcase Ventilation valve.

Most late model automotive engines rely on some form of fresh air exhaust induction to lower emission levels. Such a system requires a high speed check valve. The supplied part number is such a valve for several GM automobiles.

Kind Regards,
Dale

wildbill

Thanks Dale for clearing that up.I will check on that and see what I can come up with.Thanks for the part numbers to because my local auto parts guy is slow but he gets it right and that is all that matters.

husabutt

Dale:

When using the air pump check valve does the lack of air being able to flow back into the motor have any consequence? Most breather mods done to other motors use a filter, K&N or equivalent, citing that this will allow air to flow back into the motor during deceleration and cooling off.

LINEAWEAVER

Although of no consequence crankcase vacuum will slowly diminish once the engine has been shut down.

Kind Regards,
Dale

husabutt

Received my air pump check valve today. It seems that most if not all of the OEM cross reference part numbers are wrong on the KEM web site. I got mine from a Chrysler dealer. Part number is 04300376 and cost is about $30. Just need to scrounge up an adapter for the female threaded end and a slick way to close the frame opening.

LINEAWEAVER

The female end of the valve should be that of a standard pipe thread and a 5/8" spigot coupled to the appropriate male pipe end should be quite easy to fashion. I would suggest you then top off the complete assembly with a small K&N breather filter.

The frame spigot is easily blocked using a suitable cap such as that used to plug automotive heater line spigots.

Hope this helps.

Sincerely,
Dale

PowerCell

I got mine today, but it's not PolyVinyl Chloride ... I'm gonna return it.





~ Ken