Engine stalls after running

[Halstead666]

I have a 96 mercruiser 5.7 alpha one. The engine runs good although one problem persists.....after running the engine with load for a typical 20-30 minute cruise to a given destination @ 2500-3000 rpms when arriving at the destination I need to baby the throttle otherwise the engine will stall.....If I run down to 1000 rpms it usually will stall out so I have to slowly run it down for about a couple of minutes to avoid the stall seems like the gas in the bowl is not able to burn off from a quick downshift and the egine floods itself ......it is mostly a problem when towing tubes/ skiers when there is the need to slow down or stop quickly. Not sure if this is just normal operational procedure or if I have a problem that needs a fix? Thinking maybe the float is off? Any suggestions on what might need to be looked at? Thanks

 

[Scott Danforth]

What does the temperature of the motor look like after 20 minutes?

its either spark or fuel related.

If its spark related - could be spark module going south
If its fuel related - could be vapor lock, plugged vent, or crud in the carb.

 

[alldodge]

I would guess your flooding, time to have a look inside the carb. Your plugs are probably a little black and sooty.

 

[Halstead666]

The temp is fine and never gets over 160.......and the plugs look good. What is a vapor lock? Guess I will do a tear down of the carb this winter with a kit from Mike's

 

[alldodge]

The temp is fine and never gets over 160.......and the plugs look good. What is a vapor lock? Guess I will do a tear down of the carb this winter with a kit from Mike's

With a carb I don't see vapor lock being the issue, only with EFI