Suzuki DT50 bogging down?

[river_bouy]

Hi,
I have a 1984 Suzuki DT50.

I will try to describe the problem the best I can.

First I noticed that at low speeds, the engine was kind of surging ie. loosing power for brief periods of time and then picking up again. Engine ran fine at higher speeds.

Then, the engine started surging and loosing power at all speeds.

At first, I thought a fuel flow problem. So I tried pumping the primer bulb and the engine picked up okay again at higher speeds. However, after a while even priming the bulb does not help and I can't reach any speed above a slow idle. When I increase the throttle, the engine will kind of surge like it wants to go but will not increase speed.

Sounds to me like a fuel flow problem. What are the best order of steps to troubleshoot this (ie. simple things to do first before taking off the carbs)?

One other point, when I had the boat on the trailer I noticed that when I put the throttle forward it pushes the spark advance leaver forward, but when I take the throttle back the spark advance does not move back ??? Perhaps not a fuel flow problem but a broken part in the throttle linkage that is not setting the spark advance. Would improper spark advance setting cause the symptoms outlined above?

Thanks so much in advance for any help offered

 

[7355hpchry]

Re: Suzuki DT50 bogging down?

Sounds like a fuel pump problem. Pull the fuel line to the carbs and crank the engine. A good stream of gas should come out. Also check your lower spark plug, I'll bet its wet.

As for the timing, my DT65 was doing the same thing. I disconnected the throttle lever from the remote, then I sprayed contact cleaner around the stator. As I was spraying the contact cleaner I was working the timing lever back and forth. This will clean it up. Then I put some white grease on the slides with a q-tip. Work the stator back and forth again until it goes back on its own.

 

[river_bouy]

Re: Suzuki DT50 bogging down?

Thanks 7355hpchry.

I will test the pump the way you describe. When you say 'crank' the engine, do you mean with the key (obviously won't start)? or by hand somehow?

I was able to speak to a mechanic regarding this and he said that water in the fuel may cause these bogging down symptons. This could well be the issue as there was alot of water (from bait tank) splashing on petrol tank when this problem started. Do the symptons sounds like possible water in the fuel?

 

[river_bouy]

Re: Suzuki DT50 bogging down?

A quick update.

Turns out I had water in the fuel. My bait tank was splashing some water onto the fuel tank and it got into the system.

Mechanic came over and took apart the carbs and cleaned them up (could see the drops of water all in them). Now runs like normal.

Also replaced fuel pump and filter for good measure.


Thanks for the tips.