The Oil Tank

Allright,
today I wanted to give her a bit of a service, as I didn't know what the former keeper did to her since the last 2 years. And the bike has a total mileage of 80K on the clock. I changed the filter and let the oil flew out the tank. Some drops in the outflewing oil made me worry.
So I decided to clean the oiltank. What a good idea! What I found in the sump was at least 200cc mud under much water! I do not know how long it was there, but I am very glad to clean it. I guess the former keeper cleaned the tank after blowing up his engine 10k miles ago. But I am not too sure....
What is your expert knowledge? How often do you clean your oiltank?
Andy

Um, never.

That bike must have been sitting for quite some time. If it was ever run with water in the oil tank, you'd be doing a total overhaul right now, with MANY major new parts.

I keep a roll of strong magnets in the bottom of the oil tank, attached with a fishing leader line to a hole I put in the bottom of the dipstick.
The magnets come out and I can clean them of any gunk or metal bits.

Personally, and I can't take credit, but I think this is a GREAT idea!

I have another strong magnet attached to the same hole in the dipstick, this magnet does not sit on the bottom, but is suspended about the
middle of the oil level, this also helps to keep the flowing oil cleaner.


I do not run an oil filter on my Commando, do not believe there is any need with my magnets, and for me anyway, the less hoses, lines, and clamps to
keep an eye on, the better

I do not run an oil filter on my Commando, do not believe there is any need with my magnets

Click to expand...

Do your magnets hold brass, aluminium, synthetic materials as well?!

When I purchased my 72 comabt in July 2004, I took off the tank and was suprised, I couldn't see the bottom due to sludge.
It reminded me of the junk in the bottom of the roasting pan w/ the turkey at holiday time. :lol:
I removed the tank and placed it in a parts washer overnite continuously running cleaning solvent
passing from the oil fill hole out through the drain plug and filter orifices. It took a good 24 + hours before
I was able to say the tank looked like new inside.
It probably was never done as taking off the tank routinely appears to be a royal pain in the arse. :x
You probably did the best thing you could regarding preventative medicine for the engines sake.
My combat came w/ an oil filter so I replaced all lines and the filter of course. Get braided metal
lines for the oil lines from the pump to heads. It was strongly suggested to me and I hemmed and hawed
as I was going for a stock look. In hind sight glad I did it, if one of these babies lets loose on a ride
You may be doing a rebuild sooner than you thought. Not to forget to mention your favorite boots and riding jeans
are covered in oil :cry:
I think all our tanks have had that sludge factor at one time or another best thing is you caught it. :wink:
Marshal

Here's some factoids I've come across over the years about oil and oilfilters. Some may or may not be true, but they seem to come up again and again from reputable sources. There are three main particulate contaminates in oil. Metallic, carbon, and dirt. Metal, mostly during breakin, carbon from combustion, and dirt from the intake. You can see the filings from the rings and things on that little magnetic post in the crankcase drain plug during the first couple oilchanges. If there's any after that there are problems going on. The carbon is soot from combustion, turns your oil black and goes right through the filter. It's what people see when their oil is "dirty". It's harmless. It's what makes up sludge, and unless you throw a clot of it like a stroke, it doesn't hurt anything. Dust coming in through the carb is invisible in the oil and it does hurt things. The way the soot and the dust get into the oil is by being trapped in the oilfilm on the cylinderwall, then scraped off by the oil rings and returned back into the crankcase. A certain amount of dust of a certain size gets past the airfilter. All of the oil manufacturers recommend changing the oil and oilfilter more often if you drive in dusty conditions or are silly enough to run without an aircleaner at all. So, the metallic particles do get trapped by magnets and filters. Carbon is not trapped by either but isn't a problem and dust is not trapped by magnets but is to a certain extent trapped by oilfilters. I can't see any reason not to use an oilfilter except for the fact that it's in the worst place on a Commando. I'll bet the guy in charge of mounting the horn also did the filter.
BTW, I read somewhere that oil rings don't actually scrape oil. They are there with a spreader between them with holes in the piston to create an area of comparative low pressure, to vacuum the oil off the cylinder wall.

BP Patton,
well stated and I learned allot.
The guy who mounted the oil filter replaced the guy Wolverhampton fired
for mounting the horn
Marshal

I have re-commissioned many British bikes, all the oil tanks were cleaned on these bikes and all off them needed it very badly. Finding a 1/2 of grindings is not unusual. I found break -in metal in a tank on a bike with just 60 miles on the clock that was then stored 43 years Just a quarter inch or so. Some bikes break in several sets of rings without having the tanks cleaned time can compact this stuff down in the bottom. When hot oil cools as it's returned to the tank(the oil cooler on these Bikes) it becomes a collection point. Depending on the tank design each one has a certain capacity to hold this sludge before normal oil flow is constantly skimming it. The tank is a relativity easy thing to clean compared to the sludge trap in the tank. The oils we use in our bikes keep debris in suspension this makes a filter work well. Always put the filter in the return line just before the tank.

Say what you will about, but I am now 27 happy years with no oil filter
change oil one a year after some 1000 casual miles with mobil one 15-50 synthetic