SUZUKI DT 65 _1987 intermittent loss of power

[daniel56]

Hi all, <br /> Can someone help me diagnose a problem? I have a SUZUKI DT 65 from 1987 (not the first owner), on a GLASTRON 144 boat. <br /> Got a problem from the beginning. The engine starts just fine (every time) and runs perfect at idle. With no load RPM goes to 7000, under load <br />RPM hardly increase to 2500, engine hesitates and if I insist it stalls. Engine starts on first crank, runs well at idle, but when I try again it does the same thing. BUT, only SOMETIMES, after many attempts, it works fine for a while (over 6000 RPM on WOT and full speed). <br /> History: last owner has changed: pistons (melted,overheated engine), CDI unit, water pump, gave up and sold me the boat including the roblem as a "bonus" at a decent price. <br /> I changed: new plugs, checking fuel and fuel line including rebuilding fuel pump <br />(classic fuel starvation symptoms?) , thermostat,temperature water sensor <br />(old one was melted)but nothing changed. Compression is 115 lbs/sqin every <br />cylinder,sparks looks OK, and pumping the bulb doesn't make any difference <br />(it stays hard all time) <br /> I have a SELOC Suzuki '88-'99 Manual and a Clymer Suzuki '85-'91 Manual, and there is no qualified Suzuki delear near by here in Romania.I'm new in boating but I have some good experience in car engines. <br /> Thanks in advance

 

[jim dozier]

Re: SUZUKI DT 65 _1987 intermittent loss of power

It sounds to me like you are dropping 1 cylinder. Start unplugging spark plugs one at a time and see which one makes no difference, that would be the cylinder not working. Check the spark on that cylinder. Also, if you haven't done so already replace the spark plugs.<br /><br />My guess is that one of your carbs is clogged with gum and is starving a cylinder. You might also try squirting some premix into the carb throats (remove the aixbox) one at a time and see if it picks up any. If it picks up on one thats your lean cylinder.

 

[Yepblaze]

Re: SUZUKI DT 65 _1987 intermittent loss of power

Had a similar problem on an older Suzuki. <br /><br />Turned out to be bits from the disintegrating foam hood liner would find their way through the carb bowl vents and into the float bowls. The bits would get sucked up into the main jets and the motor would bog badly.<br /><br />Any attempt to diagnose or repair would shake the bits out of the jet(s) into the bowl only to get sucked up again within a minute or sometimes more.<br /><br />If the motor is has an appearence of kind of semi gritty stuff under the hood, clean bowls, remove hood liner, and washdown or blow off area.

 

[daniel56]

Re: SUZUKI DT 65 _1987 intermittent loss of power

Thank you for your advices,<br />I will check all, tell you later the results.<br />