Merc 3.0 running on

ardy · **Posted:** Fri Feb 01, 2008 3:41 am

Apparently the 3.0 mercruisers have a habit of running on after you switch them off .Has anyone experienced this ,I believe it usually happens in the hot weather .Something you guys in the Northern hemisphere must be longing for .
Also ,how do I go about putting photos on my threads (I am a computor retard as far as most things I.T are concerned)
Thanks Ardy

chrisvs · **Posted:** Fri Feb 01, 2008 9:53 am

We have the Volvo 3.0 (same engine) and did have the engine run-on (diesel) twice on us last summer. I did read somewhere that allowing the engine to idle for a minute or two before turning it off would help. Also, I noticed that the idle rpm setting on our boat was a bit higher than recommended, so I adjusted that as well. After the adjustment and allowing the engine to idle for a minute, I never had the problem again.

Cheers

Rob · **Posted:** Fri Feb 01, 2008 10:06 am

Same issue - After stepping up to the Premium fuel, issue resolved. Merc says that 87 octane is fine but seems higher is better...

taboo80 · **Joined:** Fri Jun 27, 2008 2:07 pm **Posts:** 4

This is most definitely a tuning problem....you can switch to a higher octane gasoline or have the timing retarded a few degrees.

Kevin

BrentC5Z · **Posted:** Fri Jun 27, 2008 2:19 pm

Welcome Kevin.

Ardy: http://www.smwebhead.com/phpBB3/viewtopic.php?f=9&t=1877

KSJ8 · **Posted:** Fri Jun 27, 2008 9:01 pm

taboo80 wrote:

This is most definitely a tuning problem....you can switch to a higher octane gasoline or have the timing retarded a few degrees.

Kevin

This is a electronic ignition, the timing Isn't like the older eng. Like the another poster said, let it idle after running it WOT or in the cruise range for a little while .My 2003 4.3L Bayliner did this & have had it happen this season W/new 2008 H190 4.3L.

Aussie_Horizon_190 · **Posted:** Mon Jun 30, 2008 12:55 am

My VP 4.3 did the same - drove me crazy. Spoke to local FW dealer in Melbourne, and he said to only use Premium unleaded, and the problem has almost completely disappeared. Our octane rating used in Australia is slightly different to that used in the USA (a bit like Japanese horsepower - they seem to have real small horses in Japan!)

www.iFourWinns.com

Merc 3.0 running on

Who is online