1999 dt140 suzuki alarm issue

[mike kelleher]

Installed used [known good] computer, had water in fuel etc. Engine starts and runs, 15/20 secs 1alarm buzz and red temp light and it may or may not go into limp mode. It will continue to run and every 30 sec it will buzz 1 time/light goes on and limp mode goes and engine rough idles or loses rpm. I have tested temp sensor[ok] replaced water pump impeller[it is pumping water, it's in a barrel],tested t-stat [ok]. I also replaced the alarm guage in dash and it still does the same thing. Major agro. Any help would be appreciated

[boats.net]

Check oil sensors.

[Solarman]

have also had alarms on over heating...

I have two dt140's, 99...
My issues were on overheating. If I ran over 2500RPMs both of mine Did start streaking and got too hot.
on both of my motors I have found the exhaust pressures blowing back through the sub-water grommet (located just under the water pump assy.) It seems someone replaced the grommets on both of my motors (improperly) before I bought them. Both grommets were burned by the exhaust caused by improperly re-installing these parts last time.
Today I finish these repairs and should know if my repairs are successful. The Manuel didn't discuss these parts as a cause of overheating, but I have done everything except pulling the engine block off the housing to check the exhaust & water passages there. Will let you know how it goes.
On my motors, the sensors were right. I saw steam as the tell-tales spitted & sputtered.
I am not saying this is the problem you are having, but no one I've talked to has mentioned the sub-water pick up as a possible problem. good luck with yours for now.

[Solarman]

update on my motors

Am happy to report both motors ran without problems for 2 hours running at 5200rpms. No overheating at all. I'm ready for fishing...
Hope you clear up your problems.

[mike kelleher]

thanks

thanks for the reply. i don't think my problem is same as yours. I am pumping plenty of water, if I take the t=stat housing an t=stat out it will pour water out while running and when together the stream is just warm but the alarm is going off constant every 30 sec or so

[Solarman]

dt 140 alarm issues...

Am just trying to offer suggestions.
I don't think the computer is the problem...
Is your Suzuki gauge giving you any codes?
If no codes, maybe the gauge is the fault?
I would also check the magnets under the flywheel... Any looseness is bad news.
(all the following occurred while trying to understand my overheating problems.)
My starboard motor gave me bad air temp sensor signal, so I swapped it with my port engine... Starboard engine gave same code again while idling just before the magnets came loose and destroyed my magneto. Both flywheel and magneto are extremely expensive... But the computer relies on the pulses from them for all diagnostics.
Am hopeful you find your problems soon.

[Gerald]

Suzuki DT 140 alarm and idles

I hope you fixed your problem.
I am having trouble with engine refusing to rev mid range and high end.
Alarm kicks in ..

[Solarman]

dt140, 99, running issues

Gerald, no need to bring up info from past. It tends to confuse issues.

Is your motor monitor giving any codes? Just turn key on (not start), and see if the lights flash any sequence?
Post your problems, and what you've checked out, out tried.