Water in Fuel in outboard

[Hot Property]

Hi chaps,

I foolishly went out to see the round island race where it was blowing a F5 at least.....

My logic was that if something happened then there were 1000 boats who may assist me!

Water was occasionally coming over the windscreen and later in the day on my way back from Yarmouth to Hamble the engine started to slow down, I thought the throttle was slipping back but no the engine was dying...

Luckily my friend was in Lymington and I called him up on the vhf and he towed me back to port.

I called seastart and they met me at the pontoon where the chap changed the fuel filter (I carry a spare) and flushed water out of the fuel line.

Plugs out and cleaned and the engine started and sounded good. I was escorted out of the harbour and made it back safely to the Hamble. Excellent service from Seastart and I will renew my membership next season!

I have subsequently fitted a water separator and filter to the boat to prevent any future occurrences.

To cut a long story short I still have a problem when running at high speed, the engine slows and it seems that water is still in the system.

I have drained the carb bowls 4 times, flushed the fuel filter and drained the diaphragm pumps but the problem persists.

Tick over up to 2000 rpm is fine, the engine is like a sewing machine.

Any ideas on what I can do to fix this please?

Engine is 2001 mercury 75 four stroke with carbs.

 

[lw395]

Are you finding any water in the carb bowls?
It could be electrical or fuel starvation?

 

[Hot Property]

I haven't seen any water as it is difficult to see any as it drains down the engine casting into the cowling.

When I opened up to 4000 rpm yesterday the engine ran fine and I got on the plane doing 22 kts for about 2 mins then the engine started to slow down.

I'm sure it is a fuel problem as by draining the carbs it has improved things...

 

[Seastoke]

I assume you have changed your fuel and maybe suplier to try it

 

[Hot Property]

Yes fresh fuel and of course the new water separator and inbuilt filter plus a further inline filter should prevent further contamination. It's what is in the engine now that is the problem. I may have to remove all fuel hoses and fittings to get rid of the water.

 

[Seastoke]

If water in the engine it would surely get pushed out the exaust

 

[Richardcm]

I had this on my inboard some I sucked most of the water out but could not get it all, googling found that turps? mixes with the remaining water and burns nicely, I eventually got around to fitting a water trap filter and still see the odd drop in the bowl.

 

[Fantasie 19]

Try changing the plugs - if nothing else it will rule it out of the investigation....

 

[lw395]

Try changing the plugs - if nothing else it will rule it out of the investigation....

Rarely a bad idea!

I had one outboard that always collected water in the float bowl, I believe it was condensation forming in the carb due to the cooling as the fuel evaporated while the motor was in a damp place.

 

[TQA]

For once the snake oil they sell in chandlers to deal with water in petrol is something that actually works.

If you think you have lots of water in the fuel then you can decant it using Baja filter which will separate the water out.