2005 4Hp Yamaha gone underwater

[winbasic]

Hi,

A misplaced step, swell at the wrong time and end result was when I hopped into the inflatable tender it's flipped and the engine cowl has ended up under water. I heard a few bubbles and it took me about 5 minutes to get it upright once I had climbed back aboard my boat. I lifted the cowl and there only appeared to be light 'dots' of water - not liters of it gushing out. I removed the plug, pull started it a few times then put the plug back in and it appeared hydro locked when I attempted to start it.

The next morning, I tried starting it and could smell fuel and then eventually got a few splutters out of it but no longer than about 2 seconds.

So what I figure has happened is the water has gone from the leg back up the exhaust and through an open port. What do I need to do to get the thing running? What do I need to check for? I'm hoping there's some simple steps to resurrect this thing as otherwise I'll have to bin it and get another because the local rates the mechanics charge is going to quickly make it beyond economical repair.

Thanks in advance!!

 

[trendsetter240]

Re: 2005 4Hp Yamaha gone underwater

Hi,

A misplaced step, swell at the wrong time and end result was when I hopped into the inflatable tender it's flipped and the engine cowl has ended up under water. I heard a few bubbles and it took me about 5 minutes to get it upright once I had climbed back aboard my boat. I lifted the cowl and there only appeared to be light 'dots' of water - not liters of it gushing out. I removed the plug, pull started it a few times then put the plug back in and it appeared hydro locked when I attempted to start it.

The next morning, I tried starting it and could smell fuel and then eventually got a few splutters out of it but no longer than about 2 seconds.

So what I figure has happened is the water has gone from the leg back up the exhaust and through an open port. What do I need to do to get the thing running? What do I need to check for? I'm hoping there's some simple steps to resurrect this thing as otherwise I'll have to bin it and get another because the local rates the mechanics charge is going to quickly make it beyond economical repair.

Thanks in advance!!

You need to get that motor started and run it as soon as possible. Pull the plug again and crank it over for as long as you can. Is this a 4-stroke or 2-stroke? If it's a 4-stroke you need to drain and change the crankcase oil.

You need to check that no water has gotten into the gasonline tank, not sure if that model has a built in tank.

After cranking the motor over sufficiently with the plugs out, squirt a little fuel or fuel/oil mix into the cylinders through the spark plug hole. Replace the plug and try to start it.

Once you get it started let it run. The longer you keep it running the better off you will be.

 

[winbasic]

Re: 2005 4Hp Yamaha gone underwater

Hi Trendsetter,

Thanks for your reply - It's a 2 stroke and after reading this that's precisely what I've done. I've managed to get it started so let it run for about 10 minutes. It sounds a little 'rattly' but I'm wondering if that's cause I'm running it in a 20 gallon tank in confined area and am probably concious of my attempts to kill it!

Plug looked a little milky so I blasted it with oil spray and then washed it in fuel before putting it back in.

Any idea where I can find a workshop manual for the engine? I'm trying to find out where the fuel filter and impellor is located cause I'm sure there's water in the fuel if it's too stroke and the plug looked milky.

 

[turn2]

Re: 2005 4Hp Yamaha gone underwater

You will have to clean the carb if the engine went under. No way to keep the water out submerged. When you remove the carb ,spray something ,{wd-40,starting fluid} whatever ,flush the water out of the reeds ,then pull rope several times with plugs out. Pump fresh gas through all lines before reinstalling the carb. if in doubt you are supplying fresh gas get a clear glass jar and pump gas in it . If it has water or trash it will appear in the bottom of the jar. Get your sample from the hose that connects to the carb and it will travel the whole system. 1drop off water will make the motor run bad, it will never burn the water out by running it.

 

[turn2]

Re: 2005 4Hp Yamaha gone underwater

Follow the fuel line to find the filter. The impeller is on the top of the lower unit.

 

[trendsetter240]

Re: 2005 4Hp Yamaha gone underwater

Hi Trendsetter,

Thanks for your reply - It's a 2 stroke and after reading this that's precisely what I've done. I've managed to get it started so let it run for about 10 minutes. It sounds a little 'rattly' but I'm wondering if that's cause I'm running it in a 20 gallon tank in confined area and am probably concious of my attempts to kill it!

Plug looked a little milky so I blasted it with oil spray and then washed it in fuel before putting it back in.

Any idea where I can find a workshop manual for the engine? I'm trying to find out where the fuel filter and impellor is located cause I'm sure there's water in the fuel if it's too stroke and the plug looked milky.

Thats good news that you got it running. Does the engine have a built in fuel tank? If so you should drain out that fuel and replace it with fresh fuel/oil mix. For the first few hours running it now you should be using a double oil mixture. i.e. if that engine runs on 50:1 mix then run 25:1 mix for the first 3 hours. Nothing more than double oil though or you will foul the spark plugs.

Not sure where to get a manual as you are in Australia. You can order from here on iboats a Seloc or Clymer manual. I believe they provide online access to the manuals right away but don't quote me on that.

As mentioned before, you should clean the carburetor to ensure that there is no water in the float bowl. You may be able to get away with simply removing the float bowl from the bottom of the carb and draining the fuel in there. Then use an aerosol spray of carburetor cleaner and thoroughly clean out the float bowl, fuel lines and throttle body of the carb.

The fuel filter should be a plastic inline filter between the gas tank and the carburetor.

Don't worry about the impellor. This incident would not have any effect on that.

 

[winbasic]

Re: 2005 4Hp Yamaha gone underwater

Thanks guys - that's excellent advice. It's got a built in tank so I'll drain that and also run my eye over the carby. I figure whilst it's off the boat I may as well change the pump and impellor. I think the impellor is on it's way out as when I take it on a run near top throttle, the tell-tale is dispelling vapour instead of a steady stream. I think that may be as a result of very few flushes after use which I'm hoping I've solved now by getting the 'wash adapter' that I can screw into the bottom of the leg.

Only problem with that adapter is you need 20 tonnes of torque to undo the screw each time as I think the salt must nearly corrode it on every time I do it up.

Anyway, I'll take the advice and as soon as I've implemented it, will report back. Thanks again for the time and effort of your response - greatly appreciated!!

 

[winbasic]

Re: 2005 4Hp Yamaha gone underwater

The motor is now running, but albeit not that well at low idle. I have replaced the fuel, the spark plug, the thermostat and the gaskets on the thermostat housing and back plate housing. I'm going to change the impellor but I'm assuming that'll only have an effect on the cooling and not so much the running.

The motor starts easy enough but when I reduce the revs, it won't idle at low speed. Where should I be looking? I purchased a Seloc manual and it talks about a timing light - can this ben automotive timing light or is there a specialised marine version? I'm assuming the timing must be out. It can't be an idle speed adjustment because if I increased the idle speed to the lowest revs where it will not cut out, I'm sure I'd snap the gearbox!

 

[99yam40]

Re: 2005 4Hp Yamaha gone underwater

Sounds like your pilot jets are fouled. You need to dissemble the carb and clean all passages.

 

[winbasic]

Re: 2005 4Hp Yamaha gone underwater

Well the followup to this is that the engine is dead. I replaced the impellor and the thermostat and changed the fuel but it was still idling rough. In defeat, I took it to the local guy and omitted what had happened just so I knew they wouldn't have any preconceived ideas. They came back to me and said that they removed the carb and found the bearings are rusted and that basically the engine was dead. They offered to disassemble further but knowing what I knew, I said don't worry and will be splashing out for another one.