Re: 92 Yamaha 200hp TRXQ erratic behavior
Thankfully, the engine is back working again.<br />For info, the fuel filter was clear and the water separator had about a thimble full of water looking contaminant free. I changed it anyway and the engine still was erratic, no improvement. I then got a fresh 5 gallon can of gas and put a new fuel hose directly into that, sucked on the hose to prime it (YUCK, don't do this at home, fuel tastes awful) and when the gas was flowing connected that line directly to the engine fuel filter, which was cleaned and clear. Still no success, same problem.<br />I bought and installed 6 new spark plugs as the old ones looked really fouled. After installation the engine was still not normal, as before.<br />I removed the carburetor cover assembly and ran the engine with the inlets fully exposed to the air. The linkages/flap things all worked in synch so that was all I could do.I didn't test drive the boat this time as the idle was erratic. The engine jumped to 4900 rpm without being in drive and it startled me, wasn't expecting the noise (engine and carb covers were off). The boatyard mechanic told me I shouldn't do that as I could blow up the engine. <br />Anyhow, I gave up and booked the Yamaha mechanic for a look at the engine/carbs. I put everything back together and took the boat for a slow speed fishing trip. On the way I increased the throttle, not expecting success and the engine is NORMAL again. Spent a lot of time test driving tonight and the engine performed flawlessly during all RPM ranges. I put as much info here as possible if it can be of use to someone else. <br />I don't understand why, but the engine now works.<br />Thank you rodbolt as your info gave me the start I needed and that's why I removed the carb cover.<br /> Many Thanks, Brian
