bob_t

Here is my question ... Person fired up the engine "dry", ie, no muffs, flush-out or anything, so I could hear the engine run (not too smart ...). It only ran for about 30 seconds. Later we put the boat in the water and ran it for ~ 1hr, water pressure showed normal on the analog gauge on the dash ( it was a Fountain), so I know it didn't cook the water pump impeller (guess he got lucky!). Had a technician scan the ECM and it showed a "low water pressure" fault set at ~ 3.0 hrs earlier than the current logged run time. I am 100% sure the engine only ran for ~1 hr after the "dry" engine run, and I am 99.9% sure that that "dry" run set the low water pressure fault. Is it possible for the ECM clock to be that far off, ie, accumulating engine run time faster than real run time? I am also sure that the key was in the off position (and literally removed from the ignition) when the engine was not running, anytime during this time interval.

Whipple Charged

Could've set code previously, run time clock is pretty accurate.

Dave_N

If the Low Pressure code was set three hours earlier, and again when he ran it for you with no water, that should be indicated by a Frequency Count of at least 1.

The first time a code sets the Frequency Count will show as 0, the second time the same code sets the Frequency Count will be 1, and so on.

What doesn't make sense is the Engine Hours should be set to the last time the fault was set. Did you get an alarm when you were there? If not, you may not have set the code.

bob_t

If I remember correctly, we got solid alarm when he ran it. Frequency counter is "1" for "Sea Pump Pressure is Low". It is 2.6 hours off from the scan time, and I know we ran it for ~ 1 hr on the lake, afterwards. When we ran it on the lake, no alarms other than over rev alarm with frequency counter showing 279 and engine run time at 141.49. Scan time was 142.1 and I'm very sure we didn't put .6 hours on it after it hit the over rev alarm. Another thing that doesn't seem right is that engine hour log shows 30.2 hrs at 0 - 749 rpm. and 45.4 at 750-1499 rpm. Combined, those two show 75.4 hrs at rpm 1500 or lower. Previous 1st owner "swears" that it had 10 hours on the hour meter when he bought it new, and now it shows 51 on the meter. Doesn't seem right. Previous owner possibly full of $hit ?