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Old 08-04-2013, 07:42 AM
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JimN JimN is offline
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Originally Posted by Mark rsa2au View Post
Ok so I pulled on the arctic gear, pulled the boat out the garage and started playing. First thing to note is how much water is needed... I sucked my 2000lt rain water tank dry (528 gallons)

Timing: The last time I checked the timing it was set at about 10 degrees at 1000rpm (using paperclip), but as it was hunting arround I set it about in the middle. NOW after much work the mark was a lot more stable and seemed to be about 2 degrees out. Set is exactly on 10 degrees, checked, turned off and resterted and checked again... stable at 10degrees

Fuel pressure: At key up and idle it was about 25 to 26psi. Adjusted Fuel pressure regulator to 30psi at idle/1000/2000/3000 rpm.

Also changed oil and oil filter while I was there.

Does anyone think the 2 degrees timing and the 4psi fuel difference would solve the issue of the lack of revs??
Which way was the timing off- low, or high? If it was low, it can affect idle, but it shouldn't be a major factor. At WOT, it wouldn't have much affect because base timing + maximum advance at speed would be near 40°BTDC vs 38° and shouldn't cost you 400RPM.

Did you put the ECM in diagnostic mode? If you saw the timing mark jumping around, your base timing ISN'T at 10°. The mark jumping means sparl stabilization is still operating and in diagnostic mode, it isn't. This is mandatory for setting base timing. You can put it in foagnostic mode by inserting a paper clip into terminals A and B of the DLC and setting the idle at 1000 RPM. The timing mark should be rock steady. Set it at 10°BTDC, snug the bolt, check it again and tighten it before removing the paper clip.

As far as 4psi, if the pressure isn't high enough, the fuel won't atomize properly and this is important because it needs to do this in order to burn completely. If it doesn't burn completely, you can't develop full power. Also, if you didn't check the pressure at WOT, it may be close, but not exact. However, it will be closer than before and noticeable.
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