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OIF Twins - rust in oil tube. #719786 12/23/17 12:59 pm
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I've got a new Triumph project to get stuck into.
I've now managed to get off the bottom plate and the oil filler cap revealing a large quantity of bright orange rust.

IMHO the level of corrosion isn't enough to structurally weaken the frame but it all needs to be shifted for it to be possible to use as an oil tank again.

My local paint strippers used to be ideal for this sort of thing, as they had quite large tanks which contained both paint strippers and then de-rust chemicals.

The frame would come back with a nearly mint surface finish.

But unfortunately the guy has invested his profits in a shot blasting plant (because it's much quicker) and has got rid of the chemical tanks.

No use fror cleaning out an oil tank and certainly not suitable for preparing a P39 type frame IMHO.
In my experience if you shot blast the oil bearing frame you ALWAYS get abrasive in the oil tank somehow, no matter how carefully you mask and block everything.

So the situation is that I either have to tackle the rust myself or find someone in the West Midlands area of England who still does chemical stripping.
I've had ideas about tipping in a gallon of Brick Acid (hydrochloric acid I think) and putting the frame somewhere warm for a while.
But I've got an idea that I might be doing more harm than good.
Any ideas or suggestions regarding this please ?

Last edited by ferretjuggler; 12/23/17 1:00 pm. Reason: My bad grammar
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Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #719787 12/23/17 1:14 pm
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Phosphoric acid will work well. Available at Home Depot etc in States in the paint section. Should be available in U.K. at the Brit “Home Depot or Lowe’s”. Cheap, easy to use.

Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #719789 12/23/17 1:35 pm
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I am a huge fan of electrolysis for de rusting, a lot healthier for you and the metal compared to using acid pickles.

You will need the following,
an old simple battery charger.
Washing soda ( not baking soda), no need to degrease items using this, bonus feature.
Water
Some scrap steel as a sacrificial anode ( some thing long and thin that will hang down the tube without touching the sides)

No need to degrease stuff, the washing soda will clean up oil and other muck.

Method, plug frame return pipe and feed pipe, fit sump plate.

Fill with electrolyte solution, 1/3 cup washing soda to 1 gallon water. You will only need a spineful, 4 pints to filler. might be trickier to do the top section.

Dangle sacrificial anode down filler, arrange insulation round top and cross bar so they dont have electrical contact.

Connect + from charger to anode, negative end to frame. Switch on charger, 12 V setting. Bubbles will appear, these are hydrogen gas, try not to smoke as you gaze at them.leave a door/window open for ventilation.

leave for a couple of days. Rinse out with fresh water, the rust will turn to black magnetite and scrub off easily, bottle brushes will help.
Once happy re oil surfaces cleaned to prevent rusting.

When I do this the ammeter on the charger barely moves, its not a huge power consumer, the results are very good, works by line of sight so nearest to the anode will clean up first. Light rusting is gone in 24 hours, heavier rusting may take a few days.

one of the best things about this is that it works with no further input apart from a rinse and clean up, allowing you to get on with other stuff while it does its thing.
I use the same process in a large plastic bucket, for other steel items, using a large magnet bar to stick the rusty smaller items on, croc clip to bar, even works on stuff like rusty exhausts.

Last edited by gavin eisler; 12/23/17 1:40 pm.

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Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #719791 12/23/17 1:45 pm
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Hi there
I recently stumbled across a very effective rust remover at Stafford show
Having picked up a T140 that had stood for a about 8yrys,the inside of the tank a mess,used a chemical called RUST ABSORB-7 (safe on aluminium)
Basically mix 20% neat to 70c water found that the warmer the better not boiling though.Leave for 24hrs and the results where amazing wash out and leave to dry.Cost £20 for 5ltrs should be more than enough.
The Company are based in Bridgtown Cannock WS11 0AZ www.thepolishingshop.co.uk

Cheers Dave


Always remember there are 3 kinds of people in this world,those that can count & those that can't.
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GT750 1974
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Re: OIF Twins - rust in oil tube. [Re: gavin eisler] #719796 12/23/17 2:32 pm
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ferretjuggler Offline OP
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Originally Posted by gavin eisler
I am a huge fan of electrolysis for de rusting, a lot healthier for you and the metal compared to using acid pickles.

You will need the following,
an old simple battery charger.
Washing soda ( not baking soda), no need to degrease items using this, bonus feature.
Water
Some scrap steel as a sacrificial anode ( some thing long and thin that will hang down the tube without touching the sides)

No need to degrease stuff, the washing soda will clean up oil and other muck.

Method, plug frame return pipe and feed pipe, fit sump plate.

Fill with electrolyte solution, 1/3 cup washing soda to 1 gallon water. You will only need a spineful, 4 pints to filler. might be trickier to do the top section.

Dangle sacrificial anode down filler, arrange insulation round top and cross bar so they dont have electrical contact.

Connect + from charger to anode, negative end to frame. Switch on charger, 12 V setting. Bubbles will appear, these are hydrogen gas, try not to smoke as you gaze at them.leave a door/window open for ventilation.

leave for a couple of days. Rinse out with fresh water, the rust will turn to black magnetite and scrub off easily, bottle brushes will help.
Once happy re oil surfaces cleaned to prevent rusting.

When I do this the ammeter on the charger barely moves, its not a huge power consumer, the results are very good, works by line of sight so nearest to the anode will clean up first. Light rusting is gone in 24 hours, heavier rusting may take a few days.

one of the best things about this is that it works with no further input apart from a rinse and clean up, allowing you to get on with other stuff while it does its thing.
I use the same process in a large plastic bucket, for other steel items, using a large magnet bar to stick the rusty smaller items on, croc clip to bar, even works on stuff like rusty exhausts.

Thanks for that !
That sounds like something that I could develop as I go along.
Presumably it will also work on fuel tanks and virtually anything else ferrous.

I can vaguely remember someone explaining to me the principles of electroplating, and how the current always takes the shortest path from cathode to anode.
This explains the terrible chrome plating on some cheapo Chinese made bits and pieces.
Like the fake Harley pattern "chopper " rear wheel rims.
Guaranteed to rust from day one because of incorrect plating technique.
I presume that with electrolysis, the same principle applies, and that anode design and position are critical.

Re: OIF Twins - rust in oil tube. [Re: Dave Lid] #719797 12/23/17 2:37 pm
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Originally Posted by Dave Lid
Hi there
I recently stumbled across a very effective rust remover at Stafford show
Having picked up a T140 that had stood for a about 8yrys,the inside of the tank a mess,used a chemical called RUST ABSORB-7 (safe on aluminium)
Basically mix 20% neat to 70c water found that the warmer the better not boiling though.Leave for 24hrs and the results where amazing wash out and leave to dry.Cost £20 for 5ltrs should be more than enough.
The Company are based in Bridgtown Cannock WS11 0AZ www.thepolishingshop.co.uk

Cheers Dave

Thanks also.
I'm going to look into this further.
I am sort of vaguely (very vaguely) connected to someone who used to work with the above.
He is into restoration of old bikes but mostly Japanese stuff.
It might be worth me picking his brains for a while

Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #719803 12/23/17 3:11 pm
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...I did not have any luck with electrolysis. I followed all the steps.

Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #719813 12/23/17 4:29 pm
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I've had serious problems using hydrochloric and especially muriatic acids where I could not neutralize the the acid left in the metal. Scary proposition when the the item is very expensive. But no kidding scrubbing with soda etc to no avail. Learned my lesson.

Do use products like Evaporust (not as effective as KBS, takes much longer), or similar product from DuPont auto paint supply, used to be called twin etch. Or this which is my go to rust remover in the last 8 or so years now. Phosphoric acid solution with additives to leave a neutral surface when done. Others have similar but I really like this product. Can be reused also.

http://www.kbs-coatings.com.au/product/rustblast/

Last edited by slofut; 12/23/17 4:30 pm.

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Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #719814 12/23/17 4:32 pm
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I would fill your tube and leave overnight or until complete, rotating part along the way.


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Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #719815 12/23/17 4:34 pm
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Phosphoric acid has the benefit of leaving a very slight etch in the metal, which resists further rusting. That means you don't have to worry about "flash rusting".


Bob, Lifetime bike: '71 T120R, bought in '71 at Ken Heanes, England.
Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #719817 12/23/17 4:57 pm
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I wasn't actually planning on diving straight in with the electrolysis.
Its fairly easy (and cheap) to get hold of some similar sized rusty steel tube to experiment with.
In fact you could apply that to all the above methods.

Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #719818 12/23/17 5:22 pm
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More than likely know the guy who does Jap restro's smile




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Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #719822 12/23/17 6:03 pm
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P. acid is naval jelly, in a liquid form, or if you prefer, the active ingredient in naval jelly. One gallon is real short money at Home Depot. I forget what I used on my frame/tank. It was not all that rusty. I remember a series of spiral brushes, including some gun brushes and a furnace cleaning big bore brush.

Last edited by btour; 12/23/17 6:04 pm.

Bob, Lifetime bike: '71 T120R, bought in '71 at Ken Heanes, England.
Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #719825 12/23/17 6:16 pm
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Quote
I've had serious problems using hydrochloric and especially muriatic acids where I could not neutralize the the acid left in the metal.


I prefer to use much milder acids which still eat the rust, phosphoric is good as its mild and also leaves a very thin layer of iron phosphate on top of steel which has anti rust properties, critic acid is also mild but no anti rust layer is left. If you flush through first with boiling water and follow up with denatured alcohol you first remove the acid with the water and then due to alcohol picking up the water leave a dry surface inside. Still does not make alcohol a good fuel as its very ability to pick up water also means it gets to drop it out in storage, so its down the plug hole with it once its done its job.

Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #719831 12/23/17 7:23 pm
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A quick search on utube will find plenty of easy DIY electrolysis set ups, worth viewing some as primers.
At work we used Citric acid flushes to clean new installed Lub oil pipe work , probably the friendliest acid to use. Pretty cheap too.


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Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #720021 12/26/17 6:44 am
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Hi ferretjuggler, What year is the frame? What are you going to use for an oil filter?

It seems when you look inside top of oil tube with a mirror they almost always have some rust on upper surface of tube, even on regularly ridden bikes never stored for long periods of time.

I've wondered about sealing the tube with a known good gas tank sealant. Of course that can have problems of its own.

I've noticed it seems no matter what kind of acid type cleaner you use on gas tanks they always rust much easier than ones never cleaned. Again rust on upper surface is common. My '73 Tiger rusted a pin hole on the upper part. 4 years after using Kreem tank cleaner. Flash rusted, & continued to slowly rust worse above fuel line. I ended up using Caswell sealer. I'm in USA.

I figured someday the frame will need attention also. I expect I'll use Caswells then. I'm using Motao in frame filter now. Comparing clean & dirty sides of filter after 1000 miles, it seems to clean oil well. I don't think it will fit in '71 frame with oil feed in side of backbone though??

Don


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Re: OIF Twins - rust in oil tube. [Re: TR7RVMan] #720044 12/26/17 6:49 pm
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The frame is an early '71 type which has the built in oil pickup pipe.
You can't use the T140 type paper filter conversion unless you hack out the pick up pipe.
Not a bad idea actually as it would give me access to get a large rotary wire brush up the main tube.

I'm generally disposed towards fitting an external cartridge type filter on the return line.
This can't restrict flow to the delivery side of the pump, but then with just a coarse gauze filter, anything in the oil tank is going go through the pump and big ends, then back through the pump again before getting to the return line filter.
Fit the paper filter on the delivery side, and if it gets clogged you get no oil to the big ends.
Sort of damned if you do, damned if you don't.
Dunno.
I could always fit both.

POR15 has been suggested as a sealant

Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #720045 12/26/17 6:58 pm
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One other consideration.
The factory countered critism of the P39 frames reduced oil capacity (compared to the '63-'70 models) by claiming the the oil bearing frame acted as a heat sink causing it's four pints of oil to run cooler than the previous five pints.
Sort of makes sense.
Now if you introduce an insulating layer between the oil and the frame, you could reduce its ability to cool down the oil.
I've no idea if this would have any significant impact but worth bearing in mind.

Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #720049 12/26/17 8:21 pm
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I have a '71'. I played around, thinking of a supply side filter. I mostly wanted one that would also trap water, in the return, as in a diesel. I actually have one in the chest. Never installed it.

There is a screen available that fits in the bottom of the tank. A small hole fits the pipe. Most people discard it. But I figure it stops some stuff. Most particles unless they are very small. Let say you are changing the oil at night and a moth flies in. Or you knock some dirt or something in. That screen should stop it. A proper spin on paper filter is easily installed on the return line. It will give you some more capacity and a small amount of cooling. You should add one.

A strong light source will allow you to look inside the frame. Just how bad is the rust? You can get a spiral brush. I don't know if you can get a metal one but nylon is readily available. You might find the type for honing available for small bore engines. Little stones that spin outward. You would have to start past the pipe and finish by hand. Or you could get a shotgun gauge cleaning brush. You could attach it to a drill and work it around. I did this, and used the smaller bores for the pipes. After the large scale is removed, if there is any, then just finish with phosphoric acid. Or if it looks good then just, Flush it with power washer or car wash. Blow it dry. Sounds harder then it is. I like the etch provided from the P acid. My gas tank was done that way and it is fine. No rust. If I knew the P acid was available at home depot, and I had rust in the oil tank, I think I would have used it. It is what is in Coca Cola and why people use that for rust.

I would never coat it with anything!. When that stuff fails you have an awful mess to deal with. People who have done gas tanks have horror stories to tell.

The screen in the bottom of the tank has to be checked now and again. Water from condensation is the biggest culprit. It will settle in the bottom of the tank and actually rust that screen, creating another hazard, which is why most people remove it. But if you drain the tank and drop the plate once a season you should be just fine. If you just use the bolt to drain the oil, the water will remain in place, unless you use a hair dryer to drive it out. It is not a big deal to drop the plate. It just means maybe the expense of a couple of new gaskets. Sometimes they can be saved and everything cleaned and reused. A little red brake clean and compressed air. You might be surprised by the water (brownish) and sludge (greyish) that will collect there. Drain the oil at the end of the season and again at the start. One for the oil sludge, the other for the water condensate. With filter, I do that too. Pain the pitou! But you just bite the bullet and do it. Don't forget the primary. Huge water collector. You can use the hair dryer there too. Drive all right out the drain plug. Another pain to get at. That is why I had a boss welded to the cover, and tapped a drain screw in. Easy primary oil change! Once the rust is out, water is the enemy.


Bob, Lifetime bike: '71 T120R, bought in '71 at Ken Heanes, England.
Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #720052 12/26/17 8:56 pm
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I have run an internal filter on my bike since 1984.
You can't add one to an earlier frame without modifications- imho my filter saved my engine when rust from the under tank tube was flushed into the main tank because an idiot (me) overfill d the oil

Condensation from normal running caused rust to form in the frame tube under the tank which contaminated the oil supply but was stopped by the internal filter

What I did was to use a home made wire brush (wire rope split at the ends) in a drill with a piece of hose on the outside as a bearing, so I could hold the hose, and move the drill up and down to target each area. I made a small led light so I could see what I was doing and used a paraffin (kerosine) gun that used paraffin and compressed air to blast the tubes.

I used a white washing up bowl under the tube sump to collect any paraffin and could examine it for particles.

The oil in frame bikes do not run hotter, they run cooler than non OIF. The frame Is an excellent heatsink.

The later type of top hat filter has a band around the base to collect sludge.

Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #720057 12/26/17 9:11 pm
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Just a few thoughts:-

Of course dependent upon usage, I doubt that the oil in most of our old Brit twins gets as hot as it should.
It should reach 80-100 degC for a major part of running time so that it can lose most blowby condensation via the breather system.
Cold oil is capable of holding only a small amount of water in emulsion. Excess will maintain a high water vapour content in the atmosphere above the oil level.
This will lead to greater rusting in that area.
Ideally in a rustable oil tank, the return oil would be able to splatter all over the internal surface of the tank. This generally happens in an ordinary tank where the return spits near the top.

I'm not totally familiar with the OIF system, so please inform me where I go astray.
Are all OIF's the same? Or did some carry the oil-bearing further up the tube to the headstock?
If the oil is only held in the vertical tube, is the tube to the headstock still open to it?
What I'm thinking of is all the volume available for holding water vapour.

I would very much doubt that the move to OIF had anything to do with oil cooling considerations. A frame largely made from a bent large tube eliminating the requirement for a costly to make oil tank is easy to understand at that time. Perhaps it was also related to the anti-emssions attempt, with vapours returning to the air intake?

There is another consequence of the revised breathing system incorporated at about the same time as OIF.
Earlier breathers spat out of the back of the crankcase (timed cam breather), so the vapour (mostly water vapour with some oil mist, any bigger oil droplets being centrifuged out in the camshaft bore) being thrown away.
In the later shared crankcase/chaincase atmosphere allows moisture to migrate from the hot crankcase to the relatively cool chiancase. Even the moisture tried to escape through the large tube, because it is uphill and cool, the moisture will condense and drain back.
I believe the problem of water in the chaincase is commonly reported in these models.

Having excess moisture in the shared system can only exascerbate moisture problems in the system generally. Dave

Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #720063 12/26/17 10:17 pm
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Just a couple of points:
a) Because the oil flow rate in the twins is so low the pressure drop across an oil cartridge filter on the supply side in the base of the oil tank is less than the head of oil above it---so the oil is pushing itself through the filter element--the pump does not need to suck it.
b) Because of the vast surface area of the filter element as long as you change the filter element at reasonable intervals--say, every year or every 3/4000 miles the chances of filter blockage are infinitesimally small.
c) If you are still bothered by filter element blockage then make a longer fixing stud and put two elements in the tank--one on top of the other.
d) Again because of the low oil flow rate not much heat is rejected into the oil and needs to be dissipated into the atmosphere by the oil tank.
Certainly an oil cooler is very much overkill on the twins.
Sorry!--that was more than two points!
HTH

Re: OIF Twins - rust in oil tube. [Re: koan58] #720064 12/26/17 10:17 pm
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AFAIK all the P39 frames had the filler neck at the rear of the fuel tank, and only the vertical part of the tube held oil.
I've seen a few modified to have the filler neck at the headstock end, but these have been modified by owners not the factory.
The upper part of the tube only acts as a venting chamber for blow-by gases trapped in the returned oil.
It doesn't even get a slash of returned oil because the return line goes to a point directly under the filler neck.
Owners like to remove the cap to check that oil is returning correctly.

I think you're right about the revised engine breather system making condensation problems worse - especially on bikes that don't get worked hard.
The 1978 T140E finally got a system I like.
Blow-by gases from the primary case and the oil tank are sucked into the air box and burnt.
They could have done that when they adopted a "proper" air filter box in 1971 but chose not to.
Probably cheaper than that ugly D section pipe

Re: OIF Twins - rust in oil tube. [Re: Tridentman] #720067 12/26/17 10:33 pm
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Originally Posted by Tridentman
Just a couple of points:
a) Because the oil flow rate in the twins is so low the pressure drop across an oil cartridge filter on the supply side in the base of the oil tank is less than the head of oil above it---so the oil is pushing itself through the filter element--the pump does not need to suck it.


If I'm understanding that correctly you mean that the oil would flow out of the tank faster under gravity than the oil pump can use it anyway ?
Therefore no chance of the filter element collapsing under atmospheric pressure unless it's totally neglected by an idiot.
I think that I'm going to hack that early type pickup pipe out.
I really don't like lots of "performance mods" on a classic bike but this could save my engine

Re: OIF Twins - rust in oil tube. [Re: ferretjuggler] #720073 12/26/17 11:03 pm
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koan58 Offline
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Joined: Nov 2012
Posts: 1,308
We've wandered a way from your original problem, cleaning a rusty OIF oil reservoir.
I know nothing of electrolytic cleaning, or mild acid/phosphoric techniques, except in the cleaning of rusty parts which then need scrubbing/flushing afterwards.
Personally, I would only be comfortable with thoroughly scrubbing the internal surfaces as best I could, and then some.
Whether that means lots of hard graft with wire brushes manually in the awkward places, spinning a brush for most of the tubes, being a chimney sweep at times, I think that is what you should do.
Followed by ridiculous amounts of flushing with hot water, in all directions, and shake it all about.
If you really wish to check, seal it up and half fill with hot water, shake it about upside down as well, then drain out through a filter paper.
I would folow this with a flush with meths, and filter it as well.
If both filters are clean, you're ok. If not, clean again.

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