davejohnson
Cadet
- Joined
- Sep 4, 2004
- Messages
- 26
OK, veterans. Need help.<br /><br />My motor: '78 Merc 900 inline 6 (#5034807) I just got it this summer. Yes, I'm a rook.<br /><br />Runs great, better than great, at 25% throttle upwards. But this motor stalls at idle speed *every time*. I changed the plugs, rebuilt fuel pump, put in brand new fuel line, bulb, and plastic tank. No fix. Gummed up carbs, right? Maybe. Old-timer at the marina says (what I gathered from behind his terbaccy) something about the carbs getting gas at idle through little PORTS, and through JETS at speed. Anyway...<br /><br />So, after reading testimony after gushing testimony about SEAFOAM carb cleaner, I plunked down $12 for two cans of the non-aerosol. This morning, I went out, launched Ol' Creaky (antique wooden Thompson) and warmed her up for a few minutes. Then, I switched lines to the temporary tank in which I had prepared 1 gallon of gas/oil and an entire pint can of SEAFOAM. Let her run for 15 minutes, then shut it off. Waited 20 minutes. Started again, and yes, the motor did smoke a bit, about 30 seconds, but the smoke was white, and not the rock-n-roll billowing smoke that I have seen described here. The smoke died out. I let it soak another 15 minutes, then started on the "gas/oil only" tank, 30 seconds of smoke again, and ran about the lake at speed to rev out the yukky stuff (hopefully).<br /><br />After 30 minutes or so, thought I'd test the low-speed put-putting, and dammitt---it still stalled. I'd bring it to idle. Little sputtering. Advance throttle ever so slightly, dead. Start again, idle high for a minute, advance throttle slightly...dead. Now if I push throttle forward abruptly, it hesitates for a second, then VOOM! Out of the hole like a rabbit. Back to the dock, I stall/started back onto the trailer. Square one.<br /><br />Now, I *did* load it up with the gas/SEAFOAM mix before I put it away today, and will go out tomorrow, with hopes not so high, and try everything again. But please tell me: did I not do something correctly? Should I have necessarily seen some degree of performance improve? I'm a bit daunted at the thought of tearing out those THREE carbs and cleaning them (properly) but is that in my future?<br /><br />Sorry this is so long. Thanks for any thoughts.<br />Dave
