I've just joined up from Australia and hope someone is better than me at diagnosing outboards. My Tohatsu 8 took a bath during a storm when dinghy sunk. I needed to go someplace soon after recovering it, so washed it down with fresh water and filled bores with outboard oil (the only thing I had handy) and left. I've since cleaned it out completely with WD40 and petrol, took the carb apart (it was gunky) cleaned it very carefully throughout, blew out all fuel channels etc. I can get it to start when I leave some petrol in the cylinders, but it quickly dies. Kept thinking the plugs (I put in new) were fouling, kept running petrol through, cleaning plugs etc, but still it just starts, runs a moment and dies. Now I think it's not getting fuel, but another carb dismantle shows all clean and clear. Starts right up with a spoon of fuel in the bores, but soon dies. Any suggestions?
Tohatsu 8hp blues
- Thread starter Mark Makai
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My mechanic tells me that an engine needs three things to work: fuel, air and a spark (ignition source). That your outboard works at all when you put fuel in the cylinders indicates that its getting air and a spark. That leaves fuel as your problem. That the carb. looks clean doesn't mean that all those tiny ports and jets are in good shape. I went through that problem with a gas powered string trimmer. I had to soak the carb in carb cleaner overnight, even thought it looked fine. That cleared out whatever was blocking the ports/passages, and it ran fine after that.
Good luck. Jim Kolstoe, h23 Kara's Boo
Good luck. Jim Kolstoe, h23 Kara's Boo
I'd check the fuel line. After the tank there is prob a line filter. The mesh is so small, water drops will cling to in absructing the flow. Clean it and the lines...tank too if you have not previously done it. Bob
The problem is that you probably only got oil in the main engine components. The jets may have still had water inside them and they may have corroded to the point that it is affecting fuel flow into the engine. I would highly recommend replacing the carb jets. Cleaning them will do NOTHING if they are corroded... and sitting in water for a few days will do that.
Had a similar problem in a Honda scooter. (no, it did not fall in the water) Tear the carburatorr down, inmerse in a cleaning solution overnight and clean passages with compressed air. Check the fuel pump.
Benny—
If the carburetor wasn't immersed in water, then it is not a similar problem. The problem Mark's engine has is due to the very fine passages in the carb jets becoming obstructed by the corrosion that occurred by letting the water sit in the jets. The symptoms may be similar, the causes are not.
If the carburetor wasn't immersed in water, then it is not a similar problem. The problem Mark's engine has is due to the very fine passages in the carb jets becoming obstructed by the corrosion that occurred by letting the water sit in the jets. The symptoms may be similar, the causes are not.
An easy check to determine if its water causing your prob...Pull the fuel line off the carb. With the flow valve opn, fuel should be running out. If its not, then there is an abstruction up stream..tank & filter.. Bob
Start at the tank and work your way up. Did you open the fuel tank vent? Check the primer bulb for cracks and correct direction, pull the fuel pump off and check the diagphram. I used to run mine with gravity feed into the fuel pump intake with a small funnel rather than drag the tank around. Did you check the choke for correct operation? Perhaps the butterflies are seized. Good luck.
Sailingdog, I'm not into semantics. Mark indicates he found the carburator gunky and it seems he has a fuel obstruction. I recommend that he checks the lines, pump and filter but if it boils down to the carburator the a thorough cleaning should be performed before any parts are replaced. No one can ascertain what the real cause is.
Might want to read again... the engine was submersed in water, and left to sit after only a brief cleaning. The carburetor wasn't properly cleaned and allowed to sit with water in it. Corrosion starts fairly quickly if there is salt water sitting, which was probably the case with the carburetor jets, which have extremely small openings and a quick rinse isn't going to clear them of the saltwater, especially if he did so quickly. Even if it did clear them of saltwater, there would still have been fresh water sitting in them.
Even a minute amount of corrosion, not visible to the naked eye, would close off the jets.
Even a minute amount of corrosion, not visible to the naked eye, would close off the jets.
Also, he has cleaned the carburetor already. From the OP:
If he has cleaned the carb—which he has—and the engine was submersed and not properly disassembled and cleaned completely immediately—which it was—corroded carburetor jets are the most likely suspect for it not getting fuel.
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