Alarming alarms

[lakemac]

I have a Volvo 5.7GXI (2004) in a Larson Cabrio 260 that has been alarming spasmodically the last couple of times I have been out in it.
Both times I have been traveling at top speed (approx 4200 revs and 35 knots) when the alarm has gone off and the revs governed back.
The first time I checked the oil and found it low so topped it up and thought this was problem fixed.
The second time I was again at wot and in a mild turn when it alarmed.Oil is still good.
Can anyone tell me what else the alarms may go off for other than low oil pressure and overheating????? (temperature was in normal range both times)
Cheers Greg

 

[Don S]

Re: Alarming alarms

Hard to say for sure, Volvo doesn't list anything by year, do you have the model number letters after the 5.7GXi, or even the Volvo SN would help.
Your problem may be the exhaust temp sensors indicating a temp in the risers over 210? a steady beep would go off and the engine would go into "Engine Protection Mode" (RPM's decreased) untill the temp dropped below 160?
Those temps would not show on the gauge, but would show up on a Diagnostic computer or scan tool.
When was the last time the impeller was replaced in the raw water pump? It could cause your problem very easily at high rpm.

 

[lakemac]

Re: Alarming alarms

The engine is actually a 5.7GXI-F (2004) but i can't find an SN number anywhere(though I do remember seeing one on it somewhere).
The impeller was replaced about 6 months ago after I accidentally dragged the leg through the bottom ,( luckily at very low speed) ,and filled the thing with gravel,sand, shell, which obviously shredded the impeller blades and set off an alarm.
I haven't removed it again since to reinspect.The engine was flushed of contaminants before this was fitted by removing the plugs at the back of the manifolds and running the engine with a second hand impeller fitted.(Great loads of gunk spewed out.) Maybee it wasn't flushed enough?? But I have done approx 9 hours since then. As I said before the temp is normal when the alarm triggers?? Should I invetigate further blockages/cleaning/flushing??

 

[Don S]

Re: Alarming alarms

I would do a test run and check the exhaust risers with an IR temp gun to see if they are getting hot at full speed. They could be getting hotter than 210? and setting off the sensors in the exhaust risers I mentioned before. If the risers stay well below 210, you can verify if the sensors are causing your problem by disconnecting them and seeing if you still get the alarm and protection mode.
If the temp of the risers actually does get near 200?, then you may still have some impeller pieces stuck in one of the risers. If the outlet of one riser is partially plugged it would not cause the engine itself to overheat or the temp rise, but it would cause the exhaust to overheat and possibly burn the exhuast hose.

 

[Billwyoming]

Re: Alarming alarms

My 03 Cabrio 310 has a buzzer going off - sounds like front bilge, but when breakers and fuses removed, still buzzing. Sound coming from where A/C is located in center front of boat cabin. Only way to shut it off is turn off 12v, which I do not want to do. Local mechanics are stumped. They think it might be connected to an A/C bilge, which appears to be unreachable! Help.
Bill at bsniffin@wyoming.com.