87 DT65 with no idle, high RPM

[ktgscg]

I have a 1987 DT65 Suzuki outboard. It worked great, then all of the sudden (in the same day of use) as soon as I start it up it races to max rpm (maybe 4000 - 5000?). I checked all the linkages and they are fine and correct. Any ideas? Could it be the reed valves? I had these replaced once before when the engine would run rough when I put it in gear. If so are they easy to replace? Thanks in advance to anyone who can offer some help!

JPG

 

[deejaycee_2000]

Re: 87 DT65 with no idle, high RPM

When last did you relace the fuel pump diaphram, I have the same motor, and have read many threads on this with more or less the same issue, and it seems that the fuel pump diaphram of this particular model have issues one time or another .....

 

[ktgscg]

Re: 87 DT65 with no idle, high RPM

When last did you relace the fuel pump diaphram, I have the same motor, and have read many threads on this with more or less the same issue, and it seems that the fuel pump diaphram of this particular model have issues one time or another .....

 

[ktgscg]

Re: 87 DT65 with no idle, high RPM

I don't think it's ever been replaced. I will try that and let you know. It may be a while though, we just received 12" of snow yesterday!!!

THANKS!!!!!!

 

[archiezift]

Re: 87 DT65 with no idle, high RPM

I had the same problem, my rpm didn't go below 3000rpm and just happened out of the blue one day. Found out that on a DT65 idle speed is controlled by the ignition timing. Pulled the throttle sensor, found some grit in the sensor with held it in about 1/3 throttle setting, cleaned it out, put it back on and hey presto, the boat now idles around 900-1000 rpm. The mechanic who guided me said it would be either the throttle position sensor or a temperature sensor. Mines a '92 DT65, and earlier ones could be different, hope this helps.

 

[James R]

Re: 87 DT65 with no idle, high RPM

If your serial number is 603134 or later then your tps is the same as the '92 model.