Mercury 4stroke EFI 60 HP Bigfoot 2007: Stalls with RPM between 1000 and 2000

[onur_birol]

Hello everyone,

I bought Mercury 4Stroke EFI BigFoot 60 hp 2007 three months ago...While negotiation with the former owner we made a small tour with the boat but i did not notice the problem since it was 5 minute tour...


It runs great at idle and at low rpms in first 15 - 20 minutes and also works fine on high speeds..

After 15- 20 minutes RPM vary and then the engine stalls when I try to set the RPM between 1000 and 2000. Also It does not stall when increasing RPM quickly to higher than 2000. When the engine starts to stalls, i let the boat idle and it boggs then die. Then i turn the key again, it starts easily but when i set the RPM between 1000 - 2000, it stalls again. Again above 2000 rpm it runs fine.. Also, i have tried pumping the fuel bulb while the problem is occuring but it does not have effect.. I took boat to Merc service in Bodrum/ Turkey.. They could not find the problem... They changed the sparks, checked filter, checked low pressure mechanical fuel pump,checked VST, checked ECM, also changed the Idle Air Control (IAC)... Mecanics connected computer but there were no errors in the system.. They could not diagnosis the problem so they could'nt solve problem.. I pay lots of money to them..

Do you have any idea about this problem?

Thank you.

Onur

 

[tommarvin]

When old ignition parts get hot, when you run at WOT or close to it for a while, they over heat, and have to cool down to work right.

I would start by testing the coils first, then test as many electrical part as possible. don't throw any more money until an error in the system.

Borrow a laptop, buy the software and cable, keep checking an error will finally appear in the system when the ignition part fails or finally breaks.

Ignition problems are tough,because they fail slowly, without errors in the system.

Keep using the boat, as best you can, and check for errors after every day on the water, TEST all ignition parts you can.

 

[Edsouto]

I have the same problem with my 60 hp 4 stroke 2013
If I run between 1000 and 2000 rpm for sometime, it begin to lost power and stall
Start, idle and above 2000, everything works ok
I saw several post with the same issue. Did someone find the answer??

 

[Edsouto]

Check vacuum leak at throttle body shaft
It will make the ecm crazy