2010 yamaha 115hp injection wont run on water

[Orwell boy]

Hi all ,looking for a few pointers ,bought a boat with above yam on it ,was run for me on purchase ,towed 200 miles home ,ran on muffs next day in garden ,took it out down slip ,started easily and off into the orwell river ,had a fast spin for 5 minutes ,noted a flashing water separator light but on inspection of filter on tank outlet noticed some taped wires and concluded the sensor was not present (first mistake ) ,carried on up the river at 5 knots to get the feel of engine before trusting it any further for another 10 minutes until cough splutter and dead ,not to restart ,got towed in , that tells the whole tale
next day checked the water separator under engine cowl and sur enough overflowing with water as was the separator can on thtank outlet
today bought new filter (yam under cowl ) cleaned everthing from tank to injector rail that was obvious but couldn,t get easily to high press pump so hoped this wouldn,t matter if I cleared all the water and pipes I could ,connected to a brand new quicksilver tank and pumped fuel up with the bulb ,and fuel in separator ,alarm gone but turned over several times but no fireing at all ,,,,,,,Any help or anybody guide me a little ,thanks

[jeffstevens763@g]

Looked at the plugs? Water gone all the way high pressure pump needs draining

[Orwell boy]

Thanks jeff ,yes did look at plugs on the night I happened and yes pretty sure they were wet with water , so guess this means high pressure pump needs draining , is this something I can do ? or are we in need of a visit to a specialist ? am reasonably capable but do struggle a bit with sight and a little weak on fuel injection as I was brought up on carbs ,thanks

[A1an]

Did you remove intake manifold and empty the VST? There is also a small gauze filter in there.


If you haven't emptied this tank there is no point going any further.


Its a common engine so there is likely a youtube video explain the process

[Orwell boy]

Originally Posted by A1an

Did you remove intake manifold and empty the VST? There is also a small gauze filter in there.


If you haven't emptied this tank there is no point going any further.


Its a common engine so there is likely a youtube video explain the process

Thanks Alan ,you guys definitely have the answers but to be honest I have just you tubed this job and I have everything from a guy finding a plastic pipe and a brass blled screw to a guy stripping the inlet manifolds off and practically dismantleing the side of the engine ,think it might have to be specialist help for me ,only thing I can see is a 3mm ish orange plastic looking turnscrew

[A1an]

Originally Posted by Orwell boy

Thanks Alan ,you guys definitely have the answers but to be honest I have just you tubed this job and I have everything from a guy finding a plastic pipe and a brass blled screw to a guy stripping the inlet manifolds off and practically dismantleing the side of the engine ,think it might have to be specialist help for me ,only thing I can see is a 3mm ish orange plastic looking turnscrew

Tried this one...?

https://www.youtube.com/watch?v=gY2RFaahio4

To be honest its a straight forward enough job, just bolts and clips.

[jeffstevens763@g]

Try danger marine on YouTube he does a lot with yams good source of info or d- Ray's shop

[jeffstevens763@g]

Thinking more about this if it were me I would get it to a trusted specialist you have had some bad luck but how long has it been running with water in the fuel fresh or salt and why that much you don't want to keep getting your days spoilt as one problem after another crops up corrosion might be an issue good luck with it.

[Orwell boy]

well ,thanks to you guys for your help .yes alan you are correct ,just nut and bolt removal and replacement so I decided to give it a go ,interestingly enough when I got the vst lid off and took out the chamber to clean I noticed the brass drain screw on the bottom ,unlike the you tube guy my vst mounted on the back of the manifold but by 3 bolts from the front of the manifold ,I think the intention is to remove the three bolts from the front and allow the vst to drop down thus revealing the drain screw ,you could then drain the vst ,however you wouldn't get the lid off to find the filter,so pleased I took the long route ,,,, however all re assembled ,pressur and clean fuel at Schrader valve on top of rack ,but wouldn't start ,however it did fire once ,but only once , however the battery must have been low as I tried for a while when I broke down ,then again when I got home a and another good session when I cleaned the pipes and lp pump ,then again after this procedure , engine seemed to be cranking fairly healthily but was below 12v I think , charging battery overnight ,then will try and buy a new set of plugs and give it another go tomorrow

[A1an]

Personally I wouldn't go to the expense of swapping out plugs, id clean and make sure of spark on all four


Did you find water in the vst?

[Orwell boy]

yes water in vst ,and worth cleaning that fine gauze in there ,thought I had cracked it but just hoping on the battery low ,stoppingme from getting running ,but thinking I may be being optimistic , could water have got to injectors and caused issues ? ,pretty sure the plugs were wet with water on original removal

[A1an]

Originally Posted by Orwell boy

yes water in vst ,and worth cleaning that fine gauze in there ,thought I had cracked it but just hoping on the battery low ,stoppingme from getting running ,but thinking I may be being optimistic , could water have got to injectors and caused issues ? ,pretty sure the plugs were wet with water on original removal

yes water can cause issues with injectors but I would still expect it to run even if a little lumpy/rough.

[Orwell boy]

Great help thanks guys ,charged battery to 13ish volts overnight and burst into life first crank this morning , did become a little more hopeful of this last night after you tubing a guy cleaning injectors , I come from a carburettor era and I wasn't even aware you needed 12 v to open the injectors up to allow them to pass fuel ,I reckon my battery must have been 11 or so volts even though it was cranking well ,did measure it but wasn't till an hour after I started charging as I couldn't find my meter and it was at 12.1 then,, thanks again

[A1an]

Good result


The battery is the heart of any modern engine, too much sensitive electrickery for their own good. It may well have be producing 12v 'off load' but as soon as you try to start the engine the voltage will drop too low.

[jeffstevens763@g]

Good result and learnt something myself re injectors any idea where the water came from? Or how it got there more to the point

[Orwell boy]

Originally Posted by jeffstevens763@g

Good result and learnt something myself re injectors any idea where the water came from? Or how it got there more to the point

I reckon the can style water separator was saturated ,and the under cowl separator was the same so the two filters had no choice but to pass water instead of fuel ,the Yamaha dash indicator flashed up a warning but being new to me I didn't know it existed but I had seen some unused coiled wires next to the tank side separator and assumed the warning was on all the time because it was disconnected ,when I later emptied the two filters into a pint glass (not to drink ) it had to be seen to be believed ,about 3mm of petrol on the top of an absolute glass of pee .
I found out about the voltage needed to open the injector after being told £45 per injector to clean ,I googled it and found an amazing method using an old tyre valve ,gluing the pipe to the dust cap from your tin of carb cleaner ,pushing the injector up the old tyre valve (valve removed ) ,fitting the dust back on the valve and other end of pipe into aerosol and happily spraying straight into the injector until it was clear ,but you had to apply 12v to open the injector before spraying
I thought it was priceless and I would love to put a link up but I don,t know how

[matata]

Well done and a great result.Youve learnt loads. Its amazing what people have put on utube. We also have a f115. We bought a racor filter assembly with a glass water drain at the bottom. We only use 2 micron filters. from a company called asap. Injectors are the new carbs...fuel has to be spotless. As a matter of interest... was the filter in the VST tank clogged or dirty? And did the vst gasket reseal or did you need a new on? NIK

[jonp]

My concern would be how water is getting into the fuel. A complete drain of the fuel tank and an authorised mechanic would be the only thing to give myself piece of mind for the next time on the water.

[Orwell boy]

Originally Posted by matata

Well done and a great result.Youve learnt loads. Its amazing what people have put on utube. We also have a f115. We bought a racor filter assembly with a glass water drain at the bottom. We only use 2 micron filters. from a company called asap. Injectors are the new carbs...fuel has to be spotless. As a matter of interest... was the filter in the VST tank clogged or dirty? And did the vst gasket reseal or did you need a new on? NIK

thanks ,sure did learn a few bits and pieces and was a great confidence booster after a corneal graft a couple of years ago ,its surprising how hard these things get with no 3d effect when you lose an eye ,so well happy and set up from help on this site , now to pass on a little ,,, yes I did this on sunday so no new gasket avail ,but yes I resealed existing gasket by careful cleaning with wd40 ,it is an o ring in a groove on the two halves of the vst ,could break if your unfortunate enough to stick to both halves , the filter in the vst is just a very fine flat mesh (plastic) and very delicate ,I used carb cleaner fired straight through the wrong way from an aerosol and it transformed from looking filmed to seeing the gauze so well worth doing

[Orwell boy]

Originally Posted by jonp

My concern would be how water is getting into the fuel. A complete drain of the fuel tank and an authorised mechanic would be the only thing to give myself piece of mind for the next time on the water.

Yes the easy solution is to run on a loose quicksilver tank at present while I collect enough containers to drain the 125 litres of knackered petrol that has laid undisturbed for several months hence the condition of it ,I should have known better however I was fooled by the fact the engine started first time every time until I hit the slip and the water and stirred it all up ,I wont be needing an authorised mechanic to tell me about the petrol and ethanol in boats debate . I would love to live without an inboard tank ,"awful things " but sometimes necessary