OIL TANK SLUDGE

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I get moisture sludge in my tank vent hose after long runs at speed. The prior owner of the bike tried to solve this problem by putting an automotive fuel filter at the end of the hose to catch the sludge. The hose sits on top of the battery. If I take a run on the freeway or ride at speed for very long, the sludge seems to get free of the end of the filter and dribble down the frame onto the chain guard. I can't believe I am the only one that gets the moisture build up in the vent hose. How are you dealing with the issue? There must be some creative issues out there.
 
You could run the tank hose into a small vented (plastic?) catch bottle instead?
 
Your question(s) are pretty open ended; I assume you are asking on behalf of your Mk III. I also have a Mk III and have never seen oil sludge, but my motor is new (fresh); here are a few questions:

What weight oil are you using?
How often do you change it?
What brand (not trying to start an oil war!!)
How much oil do you add after a full change w/filter?
Are you draining the sump when you do the full change?
Do you do a lot of short rides (less than 25 miles?) in between a few infrequent freeway rides?
Do you park the machine outside after your rides?

On the surface it sounds like you aren't getting the oil hot enough, long enough, often enough, but you could be introducing water via condensation if you let it cool outside, overnight, although your part of CA tends to be dry (all the time). There are plenty of CA forum members that may have similar experiences, do answer the above questions, it will help more knowledgible members give you insite to your issue. If your engine is tired, not a long stretch for a machine that is 35+ years old, blow-by gasses can be adding sludge causing material to your oiling system.

All the best ,

RS
 
RoadScholar said:
Your question(s) are pretty open ended; I assume you are asking on behalf of your Mk III. I also have a Mk III and have never seen oil sludge, but my motor is new (fresh); here are a few questions:

What weight oil are you using?
How often do you change it?
What brand (not trying to start an oil war!!)
How much oil do you add after a full change w/filter?
Are you draining the sump when you do the full change?
Do you do a lot of short rides (less than 25 miles?) in between a few infrequent freeway rides?
Do you park the machine outside after your rides?

Yes it is a MK III

I use Valvoline 20/50 Racing oil
I change oil at 3,000 miles (but haven't put that many miles on it since I got the bike)
I use Valvoline Racing oil
I am not sure exactly how much oil I added at the oil change
I did drain the sump
Most rides are 50 miles or under, not much freeway
The bike is always in the garage at the end of the day.

I don't know how many miles are on the bike since it had an earlier model replacement speedometer when I got it. The bike was just short of a basket case when I found it on ebay.

Thanks for your time.
 
calbigbird said:
Yes it is a MK III

I use Valvoline 20/50 Racing oil
I change oil at 3,000 miles (but haven't put that many miles on it since I got the bike)
I use Valvoline Racing oil
I am not sure exactly how much oil I added at the oil change
I did drain the sump
Most rides are 50 miles or under, not much freeway
The bike is always in the garage at the end of the day.

I don't know how many miles are on the bike since it had an earlier model replacement speedometer when I got it. The bike was just short of a basket case when I found it on ebay.

Thanks for your time.

As others have said:

You are probably overfilling your tank if that much oil is coming out of your tank-to-atmosphere vent line. Also, if you only ride your bike short distances infrequently, you will get condensation in the oil, and it'll be the first to blow out of the vent, looking like a mocha frapuccino.

But beyond all that, you should bin the filter and make the line longer, and route it somewhere where it doesn't oil your rear tire. The suggestion of a catch bottle is a good one. I'm embarrassed to say I've been seen fishing through garbage cans at the track looking for the right sized gatorade bottle (good and rigid) to cable tie to my beautiful racebike to catch residual mist that comes out from my tank vent line. You could do something similar hidden away in your battery compartment.
 
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