Suzuki DT 75 1992 will not rev.

[Carlsen]

Hello!

Short story:

Last weekend i was out boating and everything was fine, the engine ran about 2 hours at full speed. I did how ever mess up, as i did not check the fuel tank and the boat ran out of gas at maximum speed, afterwards i filled 5L in the 25L tank and sailed slowly into harbor.

Yesterday i tried to sail again, this time the engine will not rev. it maxes out at around 8 knots(the other day around 35) and it does not sound like it its going full rev. There is no difference in rev. from halfway point on the speedstick to maximum.

The engine is a Suzuki DT 75 from 1992, does anybody have any idea where to start troubleshooting or have tried this before with a similar problem.

Best regards.

[Murray]

Wondering if you sucked up some debris from the bottom of the tank and have plugged or partially plugged the fuel filter?

[Carlsen]

Wondering if you sucked up some debris from the bottom of the tank and have plugged or partially plugged the fuel filter?

Will be the first thing i check in the morning, thank you for the suggestion Murray!

[Carlsen]

Will be testing the fuel system tomorrow completely, i have another question - i pushed the oil reset warning on the side of the engine next to the tilt function - does this mean my engine will not use the oil mix the next time i start it up?

[Solarman]

No, if it were tripped, and you pressed the button it would "click" (noticeably), if it didn't click it wasn't tripped. If it clicked, then there might have been something with flow switch, or oil system that could have thrown motor into safe mode, possibly causing your motor to exhibit the problem you mention, low rpms. The filter may be clogged, or oil line kinked, if it trips again you might need to replace the flow switch filter unit, or clean it?

Otherwise, you may have pulled some trash from bottom of tank? If it didn't get passed the in-line filter for the tank, you might get by with cleaning/replacing fuel filter, also check fuel filter on motor. If trash is in fuel filter on motor, it may have gotten to the carbs? The motor fuel filter is not real good for trash in fuel, reason for most boat owners installing filters for tanks, as many small fuel stations buy lower-level quality fuel to compete with larger stations.

Good luck, post back on what you find out.

[Carlsen]

Hey all

So, here is what i have done so far:

Cleaned everything related to the battery so proper contact, changed spark plugs, blew through the hose from tank to engine, cleaned the fuel filter thoroughly.

Today i tried to sail, with a hose directly in a can of petrol with no connections and directly to the engine, and it sailed perfectly, so i am suspecting that the old tank(25 years old) which has sat for a few years, probably had some dirt getting stuck when i ran it dry - i will be installing a new tank and i will report back if it works!

Also looking at the oil usage, it looked like it smoked a bit when i ran it today - white smoke tho, so i am guessing that everything is OK, it has used the oil i put in so far but would like to make sure.

[Murray]

Draw a line on your oil tank at the current level and watch the oil level ensuring it drops with use, in the meantime I would suggest you premix oil with your fuel just in case your oil injection system isn’t working. You stated it was smoking and you are assuming the injection system is working but a little extra oil would be than no oil. Is your fuel tank steel? If so then it’s likely rusted, if it’s aluminum or plastic it can be cleaned.