Smelly KFL Breather Pipe

[Moosemeat]

For some reason known only to a previous restorer, the breather pipe on my KFL goes from the valve cover up to what looks like an intake air filter. All the other engine pictures I have seen on this site and elsewhere show this pipe as either connected to the intake manifold via a PCV valve or ending at the flame arrestor of the carburetor. Mine simply dumps the gases into the engine box. No wonder I like to drive on top of the seat as discussed in Woody Boater! I always wrote off the smell to vintage engine technology. Is this thing giving us blow-by gas smell?
What can I do to fix this? I thought I could bend the pipe down to the lead flame arrestor, but the pipe is made of small pieces of copper household water line welded together and won't budge. Any ideas? Thanks.

[jim g]

Please post a picture. All KFL crankcase vent were plumb through a pcv valve into the intake.

[Moosemeat]

The attached photo show the homemade rig that vents the crankcase gas into the engine box.
I have seen photos showing copper pipe w/pvc valve going into the fitting in the middle of the intake manifold.

[jim g]

Well you have to admit someone put a lot of effort into it. The valve cover plate you have is for the KBL engine. The one for the KFL is different. The 2 choices as to what you can do are is plumb what you have to the front of the flame arrestor or tracking down the correct parts to do it correctly for a KFL. You are correct in that a KFL is suppose to go through a pcv valve to the hole in the middle of the intake.

I will try to take a picture of a KFL I have at work and post it.

[Moosemeat]

Jim, yes someone put a lot of effort into this pipe, but then again Dr. Frankenstien put a lot of effort into his project too. You can't see the galvanized plumbing tee that carries water into the exhaust line, but that's a project for another day.
Do you think this rig accounts for some of the exhaust smell we experience?

[jim g]

The vent set up you have will give you an oily fume smell. With a possible hint of gas smell. Depending on how worn you engine is how much blow by you get. If you have a true exhaust smell then you have something leaking on the exhaust system. For an exhaust smell you could have anywhere from a leak underneath the manifold to a hole in the exhaust elbow to a hole in the pipe. If there is a pipe fitting on the elbow at the back of the manifold. It sounds like you don't have the correct elbow for the exhaust system. Can you post a picture of it?

[Pete DeVito]

The correct KFL as you will see in the factory brochure lower right bottom photo and also on my original engine. I never get those stinking oil fumes.


pete

[Moosemeat]

Jim and Pete, many thanks for the info. I think I misspoke when I said exhaust smell, it is more of an oily aroma. I have checked for exhaust leaks earlier and found none.
Looking at the engine pictures, what is the cigar shaped item projecting from the valve cover? Do I need a flame arrestor and a pcv valve on this pipe? Also, what size copper line is the oem setup? Thanks.

[Pete DeVito]

The cigar looking thing that comes out of the valve cover is a filter and I just cleaned mine real good and reinstalled it. It keeps the oil out of the PCV. I had the number off the PCV and when I put my hands on it I will post. I cleaned both parts and they were fine.
When you get the engine warm see if you are pushing fumes out of the dip stick.
good luck!

[Pete DeVito]

Ok it took me a minute to locate my KFL manual
P/N 5640 The "Ventilating Valve Assembly" (AC 1552603)
The other item is P/N 5396 The Flame Trap Assembly I believe
Located on page 8 in the manual
Pete

[davidvn]

Denny
as you know your engine had many non standard things done to it before you owned it We have fixed a good many of them. Installing the correct PCV system would be very easy if the engine blow by is to much for you

[Moosemeat]

Upon further observation, it turns out that the existing breather pipe was soldered, not welded. I removed the pipe, and with the help of my weed burner and a hacksaw, I made the pipe pictured above. I was inspired by old engine shots I've seen showing the breather pipes emptying into the flame arrestor of the carb.
I know this is not a permanent solution, but this will allow me to finish the season without those stinky fumes, and allow me time to find the parts that Pete called out. Now maybe I can sit on the seat more for a change.
Comments?

[jim g]

kfl 2 001.JPG

and with the help of my weed burner
Comments?

A bong can help with many things.

[Moosemeat]

Ya, a bong could help with many of this boats issues.