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-   General Q & A (https://www.offshoreonly.com/forums/general-q-20/)
-   -   500EFI Whipple rich running condition (https://www.offshoreonly.com/forums/general-q/379772-500efi-whipple-rich-running-condition.html)

articfriends 07-05-2023 09:49 PM
This is a NEW RECENT problem or its done it since you bought it or put it on?

MWhitney 07-06-2023 02:16 PM
Originally Posted by articfriends (Post 4872467)
This is a NEW RECENT problem or its done it since you bought it or put it on?
New recent issue. I purchased the boat with the blower kits already installed. I am just going through the boat and solving lots of small problems.

Severe lack of maintenance previously

MWhitney 07-06-2023 02:17 PM
UPDATE:

Replaced IAC valve and engine idles a lot better. Out of gear, count is around 0-10. In gear it shoots up to 140, but stays there and doesnt surge. Im assuming there may be some idle adjustment needed to get that count down in gear. Whipple manual says between 25-50 count.

However, between 1000-1700 ish RPM it still runs extremely rich. Clears up after 1700 and planes right off, runs flawless from then on.

F-2 Speedy 07-06-2023 02:23 PM
What ECM is it 4b ? still the stock whipple tune ? which are fat

sutphen 30 07-06-2023 08:35 PM
Originally Posted by MWhitney (Post 4872523)
UPDATE:

Replaced IAC valve and engine idles a lot better. Out of gear, count is around 0-10. In gear it shoots up to 140, but stays there and doesnt surge. Im assuming there may be some idle adjustment needed to get that count down in gear. Whipple manual says between 25-50 count.

However, between 1000-1700 ish RPM it still runs extremely rich. Clears up after 1700 and planes right off, runs flawless from then on.
how close are the exhaust tips to the water,,I had a boat that did what your talking about.ended up as we went on plane,the tips got close to the water and would revert till we planed up a bit and rpms climbed.I had to ride on the hatch looking down to see it.

MWhitney 07-08-2023 11:13 AM
Originally Posted by F-2 Speedy (Post 4872524)
What ECM is it 4b ? still the stock whipple tune ? which are fat
MEFI3.

Im going to assume its stock whipple tuning.

Do they tune it super rich out of the box?

MWhitney 07-08-2023 11:17 AM
Narrowed it down further. After idling for a while (20 ish minutes in gear), both motors started to load up and kind of surge. I put both in neutral and revved them to about 4k, held it there till they cleared up, then went on my way.

I tried this before i planed off. Revved up, cleared both motors out, put in gear and planed off perfect, no missing or sputtering.

To me, its loading up at idle for some reason, then consumes the excess fuel once under a larger vacuum, then cleans up.

No clue why its idling so rich, everything on my scan tool checks out. No parameters are abnormal

F-2 Speedy 07-08-2023 11:54 AM
Originally Posted by MWhitney (Post 4872645)
MEFI3.

Im going to assume its stock whipple tuning.

Do they tune it super rich out of the box?
Yes Whipple leans toward the rich side to be safe, I had similar issues till I had Boos work on mine, what plugs are you running ?

MWhitney 07-08-2023 06:27 PM
Was it fat enough to load up the engines after idling a while?

NGK3249, Teague recommended this plug with the setup.

F-2 Speedy 07-08-2023 07:06 PM
Yep, at LOTO its not uncommon to have a long idle out to main channel, what heat range are those plugs


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