Can you over fill the oil tank?

[uraceulose]

I’ve got a really slow oil leak after replacing both my oil pumps and I’m wondering if maybe I overfilled the oil tank. I put exactly 2 gallons in but there was maybe a pint to a quart left at the bottom when I did it.
The only place that I can see oil dripping is from the little valve at the top of the grommet on top of the tank that I think is an overflow valve?
Before I dive in and replace all of the lines I’m just wondering if maybe that’s a possibility

 

[racerxxx]

It's not an overflow valve, it's a breather. Look at the bottom of the tank where the big line comes from. I'll bet the black grommet is wet. Typically that's where they leak.

 

[uraceulose]

The grommets were the first thing I checked. Even have them on my watch list to buy in case. They are completely dry as well as the first couple feet of both lines coming out of the bottom of the tank where the grommets reside. The only places that are wet with oil is the breather exit nipple, the aluminum plate where the oem bilge pump was (directly below the breather exit nipple) and the oil line itself had some oil on it down there where it routes just above that oem bilge pump area.

 

[mikidymac]

I have seen that check valve leak oil when the tank was overfilled even though technically it shouldn't.

 

[uraceulose]

Thanks so much, I think it is either one of the Tee fittings, one of the oil line hoses or possibly the rotary valve cover...it is only on the passenger side engine and if I put a line clamp on both of the lines right under the grommets on the bottom of the oil tank, the leak will stop. I put a sharpie line on the tank as well to check the level and it hasn't dropped much if at all in the last 5-6 days leading me to believe it could be a motor/rotary valve/oil pump type leak rather than the lines or tank. I've now got both pipes pulled off as well as the air intakes and will get the carbs pulled if need be to get this sealed up.

 

[Sportster-2001-951C-Stock]

I keep the minimum amount of oil in my tank, check visually before each launch and when warning light comes on I add 1/2 gallon to extinguish sh warning light. This is to avoid loss of oil from unanticipated leaks.

 

[uraceulose]

Good to know. I’ve been clamping off the lines one at a time trying to find it over the last week or so...the good news is that it’s not coming from the engine I’m almost positive and it’s definitely coming from one of the lines or fittings. The only line I clamped off last night was the upper light that runs into the top grommet with the breather fitting on it and with the bottom 2 lines unclamped but looped up over the magneto housing it didn’t leak at all. Now I’ve let the rotary valve lines hang down unclamped, if tomorrow AM it’s still dry...I’m going to let the oil pump lines hang down as they are already unclamped then if no leaks after a day it would only leave the upper line that runs into the breather. I’ll then unclamp that one and see if it leaks again to be sure. Oddly the level in the tank doesn’t seem to gave dropped the last week even on the days where it leaked but it could just be because it’s a slow leak and hard to tell if it dropped .1 mm or whatever in the tank.

 

[uraceulose]

The breather/check valve is also the only thing that is wet every day when I check it leading me to believe it is slightly overfilled and somehow spitting out of the breather nipple even when it’s just sitting overnight.