erratic rpm readings

[Mr. Mark Thomas]

Hi All

Im looking for any recommendations regarding the above mentioned, erratic rpm readings and sometimes no readings at all on my smartcraft vessel views.

most of the time we could be cruising at 2050rpm then all of a sudden rpm will be fluctuating from 0 to 40,000rpm (engines still rev the same)

Also happens at neutral 600rpm then any old random number pops up as the rpm.

My first thought was could be a bad wire but everything seems fine. sometimes a fault will appear on the screens saying throttle or lever sync error or CCM: single leaver fault. The next day it will run fine without problem for 20 minutes or so then it happens all over again, both screens.

i appreciate anyone’s feedback

Topic

[Mr. Mark Thomas]

DVSR

We replaced the lift/transfer pump with new, didn’t seem to work. mechanic tested and determined that the pump was drawing too much current. We put a second new pump on and it seemed to work fine when key on/key off. The next day engine was starting and was running fine but RPM still
Erratic. Noticed that when key on on starboard side (good side) the buzzing of the cleaner then the troubles Portside. Ended up noticing that when key on, on the port side the DVSR light would go off and the DVSR would click. We’re about to replace this DVSR and hope for the best. Do you think we are on the right track?

[Mr. Mark Thomas]

what about the QSC-11 8.3 engines?

We’ve had the boat 2 years and ill’d say we have had to replaced the lift pumps maybe 5-6 times between both engines.

[Tony Athens]

The QSB 5.9 Lift pumps can create many different fault codes thru the Mercury “SmatCrap” system, and has been sore point since Day 1.

[Mr. Mark Thomas]

Tony thank you for taking the time to reply,

We are in Papua New Guinea and the local cummins techs are very unreliable so a factory reset may be off the cards? however weeks ago we un-plugged sprayed and re-plugged all pins on ECM. Our mechanic that happens to have 20 years experience with cummins Australia has plugged in his computer several times and has seen ”erratic data at throttles” or something similar
and also there was 8x counts of fault-2265 (prime pump high error) and 449-(fuel press very high) so we are having the lift pump changed this week. hopefully that will sort that out.

[Tony Athens]

Welcome to Mercury SmartCraft, AKA “SmartCrap”

1) Start by removing ALL power from the engine and the ECM for 
a few hours and then try it again.

2) Do you how how to do a factory “reset” and then start fresh?
 
3) take apart every plug, starting with the 40 PIN on the ECM, 
inspect, and spray with WD‐40 and re‐plug. Don´t forget the SIM
 to. If nothing changes, call a tech with INSITE in hand‐‐‐Pay special attention to the RPM counter hidden behind the damper on the front of the engine.. Something may have been “hit” and it out of alignment?

Welcome to Mercury  “SmartCrap”…

 
Tony

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