Oil vent tube dripping

[Lipdog]

Ever since I changed out my tanks, removing and reinstalling my oil tank vent tube in the process, the vent tube has been dripping more than it did before. When I stop the bike hot, I tend to get a small pool from the vent tube over the next few hours (probably 10-20 drips or so), and it also continues to drip periodically after, once it cools.

What is normal, and do you have any tips on how to install and orient the vent tube - both inside the tank and at the outlet?

Thanks!

[cscott]

I had the same problem and it turned out the return was sending oil along the top of the tank sent it right into the vent line. I simply reached in and brought the line about a 1/4 inch towards the outside of the tank and now it works fine.

[Skirted]

How full do you keep the tank? The positioning of the end of line/opening in the tank definitely makes a difference. Get it to the highest point above level you can and away from the return line. Not sure what's "normal" or if there is such a thing. If temps are cooler like mid 50s or below and if I'm just putting around back roads 45 mph mine doesn't drip at all or just a wee bit.
The hotter ambient temp it is, the higher the oil level in tank, and the harder I'm running it, are all directly proportional to how much drips. Average though is a 50 cent spot within 30 minutes of parking it. More if 2 of the 3 the previous conditions are present at same time. After that it will drip same amount over several more hours.

[ChiefTwoKicks]

I agree with cscott... the height and orientation of the return tube may be the culprit. If you run a KIWI oil filter (you have to shorten the return tube about 3/8") that won't allow your oil pump to puke, splattering the inside of your oil tank. Also, locate the vent tube inside the tank and be sure its not aimed toward the return tube, the vent tube should be pretty close to the
top of the inside of the oil tank. Don't over fill your oil tank. Check your oil level AFTER you start up, and warm up the engine. If your bike sits a few days, and the pump leaks a little into the sump, when its cold it looks like you're low on oil... don't add any oil 'till it warms up and evacuates the sump.
I made a "dip stick" to measure oil consumption, by cutting up a soup can, the kind with ripples in the side of the can, About a half inch wide, I made it about 3 inches long, bent one end over so that I could use J B Weld to glue the tab to the underside of the oil cap. It works great !! I can see at a glance, my oil level, which I run about 1 1/2" below the lip of the bung. The oil dip stick also acts as a running guage of how much oil I'm using when out riding my bike. Works especially well when I'm riding long distances, often going through 3-4 tanks of
gasoline on an extended ride. For me, 3 tanks of gas is about 350 miles+. My bikes don't use excessive amounts of oil (maybe just lucky,I guess) but the dip stick makes it easy to watch
whats going on when out on the road. C2K

[Lipdog]

If you run a KIWI oil filter (you have to shorten the return tube about 3/8") that won't allow your oil pump to puke, splattering the inside of your oil tank.

Thanks C2K. I do run a Kiwi filter inside the tank. Why would I need to shorten the return tube, and is this a problem for the vent?

[ChiefTwoKicks]

As long as you keep the vent line away from the oil return line, you shouldn't have problems. Just don't run your oil level too full in the tank. Hense, the reason for the dip stick I mentioned. No more guessing, you'll know exactly how much oil you run in the tank. You could mark the dip stick, with a line where you want to keep the oil level. Works for me !!
Only reason to shorten the tube is if the total length of the tube is too tall,the end of the tube could touch the inside top of the filter element. If your tube height is about right, you'll see the discharge coming out the tiny holes at the top of the filter. I run my oil tank full enough so you can see it. Although an Indian oil tank only holds about 2 1/2 quarts, thats plenty of oil for the flathead. And with todays technology, additives and such you can extend oil change intervals, although some oil brands recommend 3K-5K, I change my oil at around 1000-1500 miles, depending on all the usual factors. Such as how hard I am riding my bike... in the mountains, in a dirty or dusty environment, the ambient temps, and simply how it looks in the tank. I don't let it get too dirty or really black On one of my chiefs I run a CV Keihen carb. Its an 80"er and a 4 speed. Gets ALOT better gas milage than my Linkert equipped bikes. The oil seems to look much cleaner in the stroker,too. Maybe I'm imagining things, but I'm trying to say that the CV carb runs cleaner and leaner, which contributes to the oil being less contaminated with the residue from the unburned fuel. The top of the pistons and residual carbon deposits are significantly less running the CV carb. I'm guessing about the same results for those who run a Makuni carb or any other "high-performance" carb on a flathead. Linkert carbs work just fine. Set up right, they're pretty hard to beat. But they do run on the rich side, compared to the more sophisticated modern carbs.
Overall performance, better fuel consumption, slightly longer oil change intervals and the rest of reasons. Is it worth it ? Probably not, unless you're trying to eek out a whole lot more performance from a flathead.

[Lipdog]

Thanks C2K. Yeah, I've thought about a CV carb, but it's a slippery slope. These bikes run pretty well stock and that's part of the fun. Once I get the head gaskets fixed (ordered, see other post) I'm hoping I can get a bunch of trouble free miles with only simple maintenance. So at least for now, the only real upgrade I did was 12v, modern battery, and LED headlight and taillight for safety.