Running rich$$$$
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I am in need of some input,
I bought a 29 with a 575, it came from Eagan MN the elevation there is about 700ft. i live in Spokane WA and our elevation is 2200ft. This would this cause it to run rich?
I have called the merc dealers and none of them have ever worked on a 575sci and that makes it real hard to let someone play with it. Any input?????
I bought a 29 with a 575, it came from Eagan MN the elevation there is about 700ft. i live in Spokane WA and our elevation is 2200ft. This would this cause it to run rich?
I have called the merc dealers and none of them have ever worked on a 575sci and that makes it real hard to let someone play with it. Any input?????
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It will absolutely run rich under those conditions. The guy I sold my Sonic to with a 500EFI is now running a Whipple. He is also running at high altitude in Montana. I'm going to point him toward this thread and see if he can be of any assistance to you.
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Is it running richer out of one side of the exhaust vs. the other??? If so, you might have a cylinder going out. (losing compression) I've had that happen on a 525 once. Check the easy stuff first (sensors and such). If it still does it, do a comp test and change the plugs in the process. Then run it on the trailer for about 20 min or so and check the plugs again to see if they all are firing. That's how I discovered that I was missing a hole and a comp/leakdown test confirmed that later. Good luck!
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Thanks everybody as for it running richer on one side, no it just leaves a bit to much black on the transom. and the plugs are clean but a little dark. Tri-citys would be fun to try when the boat races are on.
Hey Sydways thanks and please do i would like to find out what he did or who did it to lean it out.
Hey Sydways thanks and please do i would like to find out what he did or who did it to lean it out.
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Yep elevation will make your motor run too rich. After a day on the water does your transom have a black soot line across it? I run on Flathead Lake at almost 2900’ and have found out the hard way what effect elevation has on boats. The problem is the higher elevation you get the less available oxygen there is in the air so the less fuel gets burnt during the combustion cycle. The safest way to fix it is to weld a bung in you exhaust for an O2 sensor and hook it up to a data logger to see what exactly how rich it is. Then tune from there. Is your 575 carb or injected?