Logo
FULL SITE MENU

Mercruiser 57350 Idle Problems

C

chicagoguy

New member
Just put a new/remanufatured m

Just put a new/remanufatured mercruiser long block in my boat. Its a 5.7 with 2bbl merccarb. The marina had it running on a stand before they put it in the boat and ran and idled great. Took it out for its maiden voyage and at first idled and ran great. I was running it fast for about 30 minutes and ran great. I then had to slow down to enter the harbor. I throttled down and started entering the habor. At this point ran fine at low rpm's. As I was entering the harbor it just died. Then it would not start without having the throttle at full. It starts only at full throttle and runs fine above 2000 RPM but when I try to go below this and idle it dies. How can it go from idleing and running great to only starting at full throttle and not idling at all? Any thoughts????
 
Its not the choke I ohmed it o

Its not the choke I ohmed it out and seemed fine. Also even if I manually open it up it still does not help.
 
Maybe a spark plug wire (s

Maybe a spark plug wire (s) came off?
Maybe fuel filter clogged?
Gas tank Vent clogged?
Fuel pump bad? (low fuel pressure at idle)?
Water in gas?
When not running can you get a squirt out of the accelerator circiut in the carb?

If not then no fuel.

Ohming out a choke will not tell you anything that I am aware of. It either opens (heats up) or it does not when 12 volts is applied.
 
Take it back to the installer.

Take it back to the installer. Running on a stand is not the same as on the water.

"I was running it fast for about 30 minutes..."

I hope that you varied the speed and not at the same RPM!
 
Wires are good. Changed the f

Wires are good. Changed the fuel/water seperator. Where is or does a Sea Ray Sundancer 250 have a gas vent? Does any one know? Yes 30 minutes at different RPMS.
 
"?????????????????????????????

"???????????????????????????????????????????????????????????????????????????????? ?????
question.gif
"
 
"it would have to have a vent,

"it would have to have a vent, trace the fuel fill line from the tank, if its one hose its internal and the vent is in the fuel fill cap, if its 2 hoses, you should be able to see where it goes,"
 
"get the aux. tank the marina

"get the aux. tank the marina used and hook it up to that and see if it runs, how much fuel was in the fuel tank, how long has it been sitting and was it treated with a fuel stabilizer to treat ethanol phase separation.if it does not run on there tank I would take it back to the mechanic like said above."
 
Back
Top