Petrol tank water in

gallardo · 19-10-2022, 10:32 AM

Hi all,

My beloved M600 (y2000) everytime it rains heavily, water gets inside the petrol tank and ends up preventing it running well (just firing one cilinder eventually) The carbs need to be drained and a lot of water comes out. Any ideas on how I could prevent de water going in AND if this is a general thing with the old monsters? Motorcycle center on Harrow road seem to think so (these guys are good)

I was thinking (as a temp solution) to cover it with a big sticker in between fuel loads

Thanks!

J.

slob · 19-10-2022, 11:16 AM

no, definitely not normal. it sounds like the filler neck drain tube in the tank is either split, perished or has become detatched. drain the tank and have a look inside at your first opportunity

utopia · 19-10-2022, 11:59 AM

Slob beat me to it but I'll post this anyway.

Firstly, I don't think this is a "general thing with old monsters".
My own yr2000 M750 does not suffer from the same problem as far as I'm aware (although in fairness it doesn't see rain very often these days).
But its not an issue which is generally reported on this forum .. in fact I can't recall a single previous instance.
Anyway, before tearing into the filler cap to replace seals suspected of leaking I would do two things ...

Firstly I would make certain that the drain hole (and its associated hose) from the filler recess is not blocked.
If you open the filler cap you will see this drain hole on the lefthand side of the filler recess. Being on the lefthand side, it will be at the lowest point when the bike is on its sidestand and so should drain away any water which gets in the filler recess before it has chance to build up to a level at which it can pass the filler neck seal. I would be inclined to blow through the drain hole using a suitably sized short length of flexible tubing. I guess you could even pour a little petrol down the hole to see if it exits via the drain hose. Its also worth checking that the hose is not kinked or trapped somewhere.
Naturally, while your looking there you will be able to see if the rubber seal on the filler neck looks ok and also if the seal area of neck itself is smooth, but I suspect that these will be fine and in any case, the drain hole should get rid of any water before it can threaten the main seal.

Secondly I would make sure that the water you're getting in the tank/carbs is not a result of ethanol in the fuel which is hygroscopically absorbing atmospheric water. I would do this by using only ethanol free fuel. The only source that I know of for this is Esso's premium grade fuel. This is described as E5 and although this grade is generally permitted to contain UP TO 5% ethanol, Esso's best (red nozzle) still contains zero ethanol in almost all areas of the UK. I never use anything else myself. It will also help somewhat in avoiding gummy residue build-up in your carbs and may also prolong the life of some rubber carb components, eg o-rings, needle seats etc. Another benefit may be a reduced tendency for the tank to rust internally (assuming your tank is steel and not plastic).

Mr Gazza · 19-10-2022, 12:46 PM

There's a quick mention of the filler cap drain on Capo's notes here; http://www.ukmonster.co.uk/monster/s...ad.php?t=39677.
There were pictures on this thread at one time, which I have pdf copies of, but cannot post sadly.

Covering your cap with a big sticker will prevent it from breathing and eventually stop the engine.

It's most likely the drain as Rob and Jeff have pointed out.
If you can't blow through it or pass petrol down it, the best thing for unblocking is a guitar string. A wire wound bottom E string would be best. Just be careful as you push it past the rubber section at the top near the filler, in case you go through the side, but after that "roger away" as Capo once said.
Also detach the rubber hose that goes into a Y piece and leads to the ground behind the gearbox and check that's clear.

Then change your mechanics as I don't think they are that good if they can't change a block connector and say that old Monsters just fill up with water.

Kato · 19-10-2022, 01:48 PM

Quote:

Originally Posted by gallardo

Hi all,

Motorcycle center on Harrow (these guys are good)

J.

If you mean Robbie & crew well yes good with most things Japanese or anything that resembles a Moped - More than that will not aired in public lest I incur the wrath of the sensitive ear brigade

Nickj · 19-10-2022, 06:47 PM

I had a similar problem, the water drain was blocked.
Took ages to clear the thing out but not a problem since.

utopia · 21-10-2022, 08:44 PM

Any progress on this ?
If you find that you think the drain is blocked and you want a guitar E string to clear it with, drop me a message with your address and I'll post you one.
Funnily enough I was out at the local musicians' sing-around the other night and I thought my strings sounded like they needed changing, so its no problem to send you an old one.

Albie · 22-10-2022, 09:06 AM

Bicycle tyre pump with a football inflater nozzle may do the trick

gallardo · 12-11-2022, 09:12 AM

Thank you for your kind comments and offers. Markus at Rossocorse managed to unblock it and the filler cap has also been replaced

Looking for second hand carbs for her now. Any tips?

19-10-2022, 10:32 AM	#1
gallardo Not Junior, Indiana.. Join Date: Apr 2004 Location: London Bike: M600 Posts: 99	Petrol tank water in Hi all, My beloved M600 (y2000) everytime it rains heavily, water gets inside the petrol tank and ends up preventing it running well (just firing one cilinder eventually) The carbs need to be drained and a lot of water comes out. Any ideas on how I could prevent de water going in AND if this is a general thing with the old monsters? Motorcycle center on Harrow road seem to think so (these guys are good) I was thinking (as a temp solution) to cover it with a big sticker in between fuel loads Thanks! J. __________________ Dale Don Dale!!

19-10-2022, 11:59 AM	#3
utopia No turn left unstoned Join Date: Jun 2010 Location: leicester Bike: M750 Posts: 4,545	Slob beat me to it but I'll post this anyway. Firstly, I don't think this is a "general thing with old monsters". My own yr2000 M750 does not suffer from the same problem as far as I'm aware (although in fairness it doesn't see rain very often these days). But its not an issue which is generally reported on this forum .. in fact I can't recall a single previous instance. Anyway, before tearing into the filler cap to replace seals suspected of leaking I would do two things ... Firstly I would make certain that the drain hole (and its associated hose) from the filler recess is not blocked. If you open the filler cap you will see this drain hole on the lefthand side of the filler recess. Being on the lefthand side, it will be at the lowest point when the bike is on its sidestand and so should drain away any water which gets in the filler recess before it has chance to build up to a level at which it can pass the filler neck seal. I would be inclined to blow through the drain hole using a suitably sized short length of flexible tubing. I guess you could even pour a little petrol down the hole to see if it exits via the drain hose. Its also worth checking that the hose is not kinked or trapped somewhere. Naturally, while your looking there you will be able to see if the rubber seal on the filler neck looks ok and also if the seal area of neck itself is smooth, but I suspect that these will be fine and in any case, the drain hole should get rid of any water before it can threaten the main seal. Secondly I would make sure that the water you're getting in the tank/carbs is not a result of ethanol in the fuel which is hygroscopically absorbing atmospheric water. I would do this by using only ethanol free fuel. The only source that I know of for this is Esso's premium grade fuel. This is described as E5 and although this grade is generally permitted to contain UP TO 5% ethanol, Esso's best (red nozzle) still contains zero ethanol in almost all areas of the UK. I never use anything else myself. It will also help somewhat in avoiding gummy residue build-up in your carbs and may also prolong the life of some rubber carb components, eg o-rings, needle seats etc. Another benefit may be a reduced tendency for the tank to rust internally (assuming your tank is steel and not plastic). Last edited by utopia; 19-10-2022 at 03:07 PM..

19-10-2022, 12:46 PM	#4
Mr Gazza Lord of the Rings Join Date: May 2013 Location: Norwich Bike: M900sie Posts: 5,806	There's a quick mention of the filler cap drain on Capo's notes here; http://www.ukmonster.co.uk/monster/s...ad.php?t=39677. There were pictures on this thread at one time, which I have pdf copies of, but cannot post sadly. Covering your cap with a big sticker will prevent it from breathing and eventually stop the engine. It's most likely the drain as Rob and Jeff have pointed out. If you can't blow through it or pass petrol down it, the best thing for unblocking is a guitar string. A wire wound bottom E string would be best. Just be careful as you push it past the rubber section at the top near the filler, in case you go through the side, but after that "roger away" as Capo once said. Also detach the rubber hose that goes into a Y piece and leads to the ground behind the gearbox and check that's clear. Then change your mechanics as I don't think they are that good if they can't change a block connector and say that old Monsters just fill up with water. __________________ Last edited by Mr Gazza; 19-10-2022 at 02:58 PM..

19-10-2022, 06:47 PM	#6
Nickj Too much time on my hands member Join Date: Jun 2007 Location: Forest Of Dean Bike: S2r Posts: 3,190	I had a similar problem, the water drain was blocked. Took ages to clear the thing out but not a problem since. __________________ "The final measure of any rider's skill is the inverse ratio of his preferred Traveling Speed to the number of bad scars on his body." Song of the sausage creature

22-10-2022, 09:06 AM	#8
Albie Fanactical volunteer Join Date: Oct 2003 Location: Kent Bike: M900 Posts: 9,030	Bicycle tyre pump with a football inflater nozzle may do the trick __________________ http://albies93m900.blogspot.co.uk/

19-10-2022, 11:16 AM	#2
slob . Join Date: Jul 2003 Location: East London Bike: Multiple Monsters Posts: 9,712	no, definitely not normal. it sounds like the filler neck drain tube in the tank is either split, perished or has become detatched. drain the tank and have a look inside at your first opportunity

21-10-2022, 08:44 PM	#7
utopia No turn left unstoned Join Date: Jun 2010 Location: leicester Bike: M750 Posts: 4,545	Any progress on this ? If you find that you think the drain is blocked and you want a guitar E string to clear it with, drop me a message with your address and I'll post you one. Funnily enough I was out at the local musicians' sing-around the other night and I thought my strings sounded like they needed changing, so its no problem to send you an old one.

12-11-2022, 09:12 AM	#9
gallardo Not Junior, Indiana.. Join Date: Apr 2004 Location: London Bike: M600 Posts: 99	Thank you for your kind comments and offers. Markus at Rossocorse managed to unblock it and the filler cap has also been replaced Looking for second hand carbs for her now. Any tips? __________________ Dale Don Dale!!