Noise in engine... help!

[BrettL]

Hello. I took my Suzuki DT75 out on the water the other day, the motor was running perfectly. I ran out of gas in one tank and then the problems began, I switched tanks, the motor started up and ran awful, no power at all, I took the motor home and flushed the salt water out, the motor started strong and still ran a little ragged. I took it out again yesterday, the motor started strong and still ran a little ragged once again, but I thought it would clear itself up once i got out of the channel, the problem got much worse however. The motor kept making an odd "chirping" sound, I assumed it was backfire? It would run for 10 seconds at the most and stall, if I was able to get the motor running long enough to open it up in neutral, it would run, but on 2 cylinders. I eventually got towed in from my uncle who owns a sailboat. I checked fuel lines, primer bulb, everything was fine. The plugs are new, the gas tanks we're just cleaned out and the fuel filter is new. Can anyone help? I really would like to solve this today and get out and see some fireworks.

 

[BrettL]

Re: Noise in engine... help!

If I cover carb #2 the motor sounds like it wants to run right and then just goes back to the old problems. Is it carbs or can it be electronic ignition? I've also heard that the flow sensor can engage the rev limitor to protect the engine, could this be my problem? The water light has been on lately and the motor has a strong tell tale and does not overheat. Somebody please help!

 

[31900]

Re: Noise in engine... help!

Brett,<br />I hope you don't have the problem I had with my 1986 DT55. The chirping sound is a giveaway. The crankshaft is in sections and pinned in place. These pins can come loose and the crankshaft sections move resulting in the timing being all over the place. To check for this, take off the fly wheel cover and remove the spark plugs. Identify the timing marks for the relewant cylinders. Insert a long screw driver down the plug hole to touch the top of the piston and slowly rotate the motor. The piston should be felt to rise to the top at the timing mark. Check each cylinder.<br />If you find that the timing marks do not coincide with the rise of the piston you are in deep bother. It will require a rebuild (Expensive and consider fitting new rings etc when you do it)with the crankshaft being reset by a Suzuki specialist (Suzi Motor cycle repair if no OB suzy mech is around.) This has happened to me twice. On the second time round I asked the crankshaft repairer who was a motor cycle man to weld it in place. No trouble since. I hope this is not your problem but it took me weeks to figure it out when it happened to me. Good luck.

 

[jim dozier]

Re: Noise in engine... help!

Most likely the "chirping" or sneezing is the result of a lean mixture associated with dirty carbs (see your other long post). Time for a carb rebuild.

 

[fridays]

Re: Noise in engine... help!

jimd has the likely answer. Adam1 had a problem that only showed up in the first year (1986) 55 and 65hp. No other suzuki ever had the problem. If it's chirping it's lean..do the carbs.

 

[BrettL]

Re: Noise in engine... help!

I appreciate all the help. From what I've been reading up about the Suzuki dt75, its unlikely that it is the crankshaft, but only time will tell. I will keep updating on what the problem was. Thanks for everything.<br /><br />Brett