2003 Yamaha 225

[patrick16]

I have a 2003 Gulfstream with a 2003 Yamaha 225 4 stroke (approx 1,000 hrs) on a and it runs great, but sometimes when I start it black flakes (maybe carbon?) come out of the exhaust. Any idea what this is? Should I be concerned?

Thanks for any help.

Patrick

 

[gw204]

Do a search for "F225 exhaust corrosion". Hopefully that's not your problem, but it's something to check on.

 

[HMBJack]

Patrick,

Since you have 1,000 hours on it, that is at least carbon build up and possibly (hope not) the exhaust corrosion issue we've all heard about.

If it were my engine - I'd do 2 things (others on this site may have other ideas):

Number 1 - add a shock treatment of Ring Free or Sea Foam to your fuel. The best way to do this is to remove your water separator filter (big blue 10 micron one), drain out the gas, fill it with a pint of Sea Foam or Ring Free, then re-install it (I'd use a NEW filter).

Number 2 - if you do have the exhaust corrosion thing going on, you will eventually, and gradually, hear an over heat alarm go off at some point. If, when, this happens, you will need to limp home, haul the boat and have a guy diagnose it. Then buy the Yamaha kit to fix it (around $1,000 I think). Then find some Yamaha Technician or shop who has done it before. It's not the end of the world if this is the case - just something you can do in the off season which ain't that far away. Once done, your engine will out last you!

My bet is it's simply a bit of carbon build up which the Sea Foam or RF will clear up. You might also change your plugs AFTER you do the shock treatment as they will surely be ugly after the carbon burn off is complete.

Good luck!

 

[drbatts]

Above advice seems like a good start. Never tried sea foam in the fuel filter but have run it through engines through a small red tank. When I replaced the exhaust on my 02 f225s last year. I never got the over heats, I noticed the problem due to bubbling around the lower unit from exhaust escaping, and a different pitch in the exhaust noise.

 

[seasick]

Above advice seems like a good start. Never tried sea foam in the fuel filter but have run it through engines through a small red tank. When I replaced the exhaust on my 02 f225s last year. I never got the over heats, I noticed the problem due to bubbling around the lower unit from exhaust escaping, and a different pitch in the exhaust noise.

I don't think my Yami goes into limp mode when it overheats ( Yup the plastic bag scenario).

 

[Fishshoreman]

I have not heard of burning straight sea foam. I have used a mixture (suggested on another website) of 3/4 gal of fuel mixed with a pint of seafoam. Run the engine in gear between 1500-2500RPM for 15 minutes. shutdow and let sit for 15 min. Restart and do the same thing again - run 15, wait 15. The second run should smoke a fair amount if there is a large carbon build up. If she smokes bad do one last run the same as the first.

You won't need to change plugs since the mixture will clean the plugs as well as the combustion chamber. It is sensor safe as well. Let us know how it goes.

It made a big difference on my Mercs.

 

[patrick16]

Thanks to all who responded. This is very good information. I will let you know what I end up doing and what the result is.

Thanks again, Patrick