MTFCA Forum

While installing the Columbo magneto setup on the speedster project, I noticed that the way the oil filler cap mounts that it is steel to steel and no provision for any crankcase venting. My engine is a 1919 two valve cover style engine, so the two seperate valve covers do not allow any ventilation at that point.

My two ideas are to make a custom transmission door with some kind of a vent, or since I am using a 26-27 style hogs head, and I have no Ford magneto inside the engine I may be able to put a vent of some kind where the unused mag post screws in.

Has any one else using a Columbo mag noticed any crankcase venting issues. ?? It seems like lack of good venting would cause oil leaks. (more than normal). The later one piece valve cover engines may vent enough at the center of the cover to not have any problems. ??

I'm using a phone to post this, I can add photos later if needed.

Any input is appreciated ...

I seem to remember the Columbo breather cap as an iron casting with little or no machine work other than the screw... may not be “good” crankcase ventilation, but certainly a far cry from a “good” seal

You could always make a fluted spacer for the filler cap to allow more breathing...?

Kevin, My oil fill cap is as you describe. Just a cast iron casting with no machining. It does not seal shut, but it does make a fair amount of contact. So a little venting is possible, but it would be very little. A fluted liner does offer a fairly simple fix. I wonder how much venting is enough. The stock mag post screws into a 1/2 inch threaded hole. It would be really simple to vent it at that point, but I'm unsure if that would be enough.

Thanks for the input.

A simple solution is a spacer on the cap thread to keep the cap from seating tightly against the filler neck. Suggest you also put a chain on the cap so it does not get "lost".

Here is the cap, it doesn’t come close to sealing. As dan said you could put a washer on the threads and have more space. I don’t know how you could put a breather on the hogs head and keep it from pumping oil. It also has a small hole in it which may have been for a tether.

Andy

Andy, Your cap is just like mine. although mine does not have the small hole.

I think I can screw a 1/2 inch "bayonet" style pipe fitting into the hogs head, where the mag post is supposed to be, and hook a rubber hose to it and run it to a vent position somewhere high on the cowl. That should stop any oil leaks. (I think)

Here are some photos of what I built today. It may be a little "over engineered" but I think it will work OK. The first photo shows my complete setup with the stock oil fill cap in place without my new accessory crankcase ventilator ... "an accessory on an accessory )

It is built with scraps from around the house and an old chevy hubcap (possibly a 490 ??)

I think that's more than enough Donnie. If that breather doesn't handle your blowing you have bigger problems.

Andy

Looks great, but I would think that chore boy would not be needed. Example there are times of the year that I have a real condensation issue with my engine. If I have a cap on with the screen, the moisture just collects in the fill spout area, if I take it off or use a cap with out screen it seems to evaporate better. I am thinking as high up as that neck goes I don't think oil coming out should be an issue.

Mark, Good point. I will keep an eye on it. I mostly added the mesh to keep out bugs. It is a simple matter to remove the mesh if I need too.