How to clean a tank inside?

[Pomp1]

does anyone know of any flush stuff to clean the inside of a old carbed (completely sealed) tank? I've got a feeling something is inside the tank, as sometimes feels like not enough fuel is coming through. I've already blown an airline and checked all breather, but no luck..
Cheers,
Pomp

[gary tompkins]

Steam clean or pressure washer followed by a blast with a compressed air blower?

[Capo]

What lays within the tank will not affect the fuel flow until it gets picked up by the pump and sent to the filter which if there is significant debris, will block up and reduce the flow.

In such cases, the proper way is to clean all debris and rust from the tank and coat it to prevent further rusting.

One way is to put a handful of granite chippings ans some petrol in the tank and shake it about to dislodge the rust by impact, a fair bit of shaking is required, you could use this as your daily workout :D

There are also some chemicals out there that are designed for this.

I would use a combination of the two

[Ducmon]

if you get por 15 to seal the tank for 20 litres, it comes with a really mean tank flusher and anti corrosion fluid. I know where to get it Berlin but I am sure that it is available in Britain.

one bit of advice where rubber gloves that stuff is crazy.

here is a firm selling it http://www.holden.co.uk/displayproduct.asp?sg=&pgCode=&sgName=&pgName=&agCode=&agName=&pCode=094.940

[Pomp1]

No pumps here Capo, just the vacuum pump after the filter. Old Skool ;)

[Stuart42]

Best to count how many stones you put in then you know how many are to come out.

Cheers
Stuart

[Capo]

Best to count how many stones you put in then you know how many are to come out.

Cheers
Stuart

Indeed, I've seen a chain used instead

[Capo]

No pumps here Capo, just the vacuum pump after the filter. Old Skool ;)

Even worse, no pressure to push the fuel through a restricted filter

[Pomp1]

The problem doesn't seems to be rust, I've changed filter and opened the old one and there are no traces of rust, I wonder if a larger body has found its way into my tank and is blocking the outlet.
Emptied and blown into it with a line and seemed to have cured, but as the petrol level dropped the bike stopped and then started again..

[utopia]

.... I wonder if a larger body has found its way into my tank and is blocking the outlet.....

Like a dead spider, earwig etc. perhaps....?
Maybe a flake of paint from somewhere.
Even something which has always been stuck somewhere in there, but has only recently come adrift.
I guess paraffin is cheap enough as a flushing agent....and it'd come out clean enough to keep for future use anyway.
I suppose its too much to hope that the object floats (and only blocks anything when the level in the tank drops really low ) ? ...you could imagine a dead spider might.
You might get lucky and spot it if you brim the tank.....or unlucky and have to then drain a full tank, to clean it out.

I knew a guy who actually saw a big fly take a kamikaze dive into the 2-stroke oil tank of his suzuki super six as he'd just finished filling it up.
He had to drain the lot, there and then.

[Dookbob]

After reading the posts on this I would be checking the fuel tap out carefully. Followed by the fuel pipes.

[Pomp1]

After reading the posts on this I would be checking the fuel tap out carefully. Followed by the fuel pipes.

Fuel tap not there. I've checked all pipes, disassembled the fuel tank outlet and drained the tank, cleaned all breathers and stuff..runned like a train for 70 miles then conked on me

[Pomp1]

what about using this stuff (http://www.merlinmotorsport.co.uk/p737/56-CUBES-TANK-FOAM-(CUBIC-FOOT)/product_info.html) as theory goes as long as the "whateveritis" gets trapped between the cubes and not between the cube and the outlet I should be OK. Shouldn't reduce flow, should it?

[rollo22]

Could be a perished fuel pipe on the inside (looks ok on outside)

[Pomp1]

Could be a perished fuel pipe on the inside (looks ok on outside)

the plot thickens..is there a fuel pipe on the inside?

[analogue_rogue]

check your fuel pipes are rigid on the inside. i had a fuel pipe like rollo says. they are braided in between two layers or rubber (its more complicated that that and not just rubber but for basics sake)

and what happens is the inner set or rubber seperates and closes on itself but you cant see it from the outside.

Best way to check is to try and roll the pipe in your fingers to try and make it oval, the parts that have seperated will feel "softer" because the wont have the support from the inner layer.

[Ducmon]

I had the same symtoms as you have got. I found out after getting a new tank and cutting a hole in the old one. That somebody had repaired a fuel leak in the past and that the gunk that they had used was braking up and blocking the fuekl outlet occassionaly.

I hope that it is not the same for you as this was expensive, new tank respray and badges.

best of luck.

ducmon

[Dookbob]

The fuel pipes on my last monster had a coiled wire spring running through the bore which prevented the pipe from kinking and would also prevent the inside of the pipe from collapsing. Fitting this type of fuel pipe would at least eliminate all the pipe problems for you.
The other thing that it could be is the pump itself, which could be allowing petrol through when the tank is full, but not when it is half empty. I have never had to take one of these vac type pumps apart yet, but I understand that a kit of new O rings is available to service them with.

[utopia]

Fuel tap not there.....

Do you mean you've removed/bypassed the tap, or do you have one of the vacuum operated taps which work automatically, so you don't notice they're there ? If you have one of those, I guess it could be failing (or its vacuum supply pipe could be leaking).
re. fuel pump repair...checking previous posts..... Allensperformance do vacuum pump repair kits. I think someone also posted that there's a repair kit available which is aimed at cars, but I can't find the post now. Or maybe the vacuum pipe to the pump is leaking.
Mind you, if blowing an airline backwards into the tank cured it temporarily, then your original assumption of a blockage inside the tank does seem possible......did you blow directly into the tank, or could it have been via a vacuum fuel tap (which might have damaged the tap in the process, perhaps) ?

[gary tompkins]

Some carbed monsters don't have fuel taps fitted - depends on model/year

[Pomp1]

Cleaned all inside, connected a pipe to a vacuum cleaner and aspirated inside, various tricks and things..seemed to have cured (for now) as now I've got a nice flow rather than a dribble. Any idea on that foam anyone?

[jerry]

i had a recent problem when the 750ss kept running out of fuel even with new filters and full tank ...it turned out to be a blocked air vent!!!!!!

[Pomp1]

All air vents have been checked, the dribble continued even with the tank cap open..

[analogue_rogue]

From tank or filter?

[Pomp1]

from tank, filter is brand new

[utopia]

I can't see how the foam pieces would offer any solution to your problem.

[analogue_rogue]

Ream the tank out till it flows

[utopia]

Have you tried draining the tank and peering inside with the aid of one of those extending dentist's mirrors and a powerful lamp or two ?
I was able to inspect the insides of my rotting dominator tank in this way.
You need excellent lighting, and the ability to see things in reverse, but it gets easier after a while.

[Saint aka ML]

You could use one of those small key ring cameras on telescopic, flexible arm. I had done that were a £10 camera and £4 small led flash light were attached and then I pushed it in and started turning.

[gary tompkins]

You could always contact Ricky and ask the little irish fellow to clean it from the inside :chuckle:

[seby]

hi Max
try to find an ABS tank for your carb monnie
i saw someone around :)

[Pomp1]

Devised a cunning plan for this. I've flushed and vacuumed the tank inside. In the mean time I took the drain bolt (useless 99.9% of the time), drilled through and welded a hose fitting I had lying around. The result is this:
http://i703.photobucket.com/albums/ww40/pomp_one/various/IMAG0055.jpg
http://i703.photobucket.com/albums/ww40/pomp_one/various/IMAG0054.jpg
I'm going to source out a t-piece tomorrow and do a 2-in-1 pipe to the filter. no problems with flooding as the vacuum pump will take care of flow.
So as theory goes if one gets blocked ever again the other will take care of the backup.
Sometimes a bit of lateral thinking goes a long way..

[Dookbob]

Cute, but I wouldn,t do that . If you fill up from a garage whose storage tank is getting a bit low, you could get a gulp of water in your tank along with the petrol. Then the water will go into your fuel system instead of collecting in the lowest part of your tank, which is where the drain tap is situated.

[Pomp1]

Cute, but I wouldn,t do that . If you fill up from a garage whose storage tank is getting a bit low, you could get a gulp of water in your tank along with the petrol. Then the water will go into your fuel system instead of collecting in the lowest part of your tank, which is where the drain tap is situated.

The petrol outlet sits lower than the drain pipe, and in a worst position as is wedged with about 1/2 inch between walls.