DF60 Suzuki - Problem

[rasti70]

Hello,

I have a Suzuki DF 60 where I had changed the
crankshaft, one piston, all seals etc.

The engine runs but still has some problems when running
around 3000-3500 rpm.

I already tried a new mapsensor and checked for false air leaks.

Video with Mapsensor connected:
http://www.regio.com/mit_mapsensor.mpg

idling is stable, but the motor tends to pulsate/oscillate
around 3000-3500. Sometimes the rpm corresponds nicely
to the lever position but sometimes i get these pulsations.
You see no error code is blinked out and you hear a short
beep every 4-5 seconds which I cannot get rid off.

Video with disconnected mapsensor
http://www.regio.com/keinmapsensor.mpg

idling is not stable stable, but the motor does not tend to pulsate/oscillate
around 3000-3500. The rpm always corresponds
to the lever position, no pulsations.
You see that the mapsensor error code is blinked out
(which is quite normal since it's missing) and you hear the short
beep every 4-5 seconds which I cannot get rid off.

I want to get rid of the 4s interval beeping and I want the
system to run with the mapsensor connected.

I am kind of lost now, don't know what else to check

Please help.

thanks

Ralf

PS: All testing with the gearcase under water and no prop. mounted.

[boats.net]

Have you had a computer diagnosis completed? If not I recommend it, the computer will tell you if all the sensors are with in specs.

[rasti70]

before overhauling the motor, the engine had been read out but
the dealer did not print out or store the results. this was just ignored
then because they detected that the crankshaft was stuck...

Now after overhauling there has been no computer diagnosis yet,
but this would the next step then...I have to drive 1-1/2 hours to
get the boat to the dealer and prefer to avoid that.

Regards

Ralf

[rasti70]

Have you had a computer diagnosis completed? If not I recommend it, the computer will tell you if all the sensors are with in specs.

computer diagnosis completed, electronically everything OK, no permanent errors, injection OK, etc.

Since idling could not be well adjusted the suzuki tech guessed the IAC valve may not be working well so it was changed.

Result
- no speed oscillations at 3000-3500 anymore, just speeds up fine.
- the unpleasant beeping (short beep every 3-5 s) persists.
- unstable idling persists

Any ideas ?

thanks

Ralf

[rasti70]

Engine now but idles unstable, tends to stall. The buzzer develops
a series (4-5seconds) single beep buzz with no warning light flashing.
The beeping can be switched off by pushing the ignition key in.

- Valve clearance is adjiusted
- replaced MAP sensor and IAC valve
- new oil, new sparks
- checked for false air

The IAC valve has been replaced because my Suzuki tech told me
after a ECM computer analysis that the ECM, injectors, sensors etc.
are fine.Since he could not adjust idling properly he guessed the IAC
to be the culprit (because this was the only remaining element for air intake regulation). Therefore it was changed. Idling seems to be better now but still not OK.

From the service manual, all cautions and self-diagnostic systems are associated with a warning lamp pattern but in my case that lamp has no flashing at all. From the service manual self-diagnostic system, the buzz sounds seem to fit with Rectifier & regulator, however the lamp has never flashed either engine is running or not running. Anyway I tested the following:
- DC voltage while running is 14v approx, so that's fine. Disconnected the
alternator coils (so the engine ECM only sees 12Volts), bit buzzer keeps on
beeping.. Checked the 6 diodes of the regulator, all are fine. So I suppose the
rectifiers and regulator are OK.

So idling is unstable, tends to stall, I am unable to adjust it to 600/760 rpm
with closed/opened silencer hose and I get this beeping. Any ideas ?

[boats.net]

Have you checked fuel pressure? Should be around 40 psi at all times.