Stalling Issues?

[Dennisjr13]

I have a 1994 18ft Sea Ray with a Mercruiser 4.3L V6 (2bbl carb and thunderbolt ignition) and Alpha One Gen II outdrive.

The engine will run for 15-20 seconds at idle in nuetral, but will then stall. Revving the motor to 2-3000 RPM did not help as it would still stall after 15-20 seconds. It does not run rough, and ran fine last season. It was winterized with new fuel/water seperating filter, carb inlet filter, and fuel stabilizer.

The electronic fuel pump was replaced approximately 5 years ago. Replaced the lower unit shift cable last year (see this thread from last year), as well as the plugs, wires, and distributor cap/rotor.

Is it a fuel problem?

 

[JoLlY_RoGeR_ARRRR!!!!]

Re: Stalling Issues?

Check the gas vent for any clogging. Then check your fule pressure from your pump.

 

[cooter2506]

Re: Stalling Issues?

There is an oil pressure switch that controls fuel pump when engine is running. Jump it out and see if it stays running then. It is located, if facing engine, on the right had side lower part of block. Should have two wires. Remove them and jumper them. That test of course is assuming you have oil pressure.

 

[Don S]

Re: Stalling Issues?

Here is the wiring diagram for the system so you can see how the switch figures into the system.
When you start the engine, power from the starter solenoid powers the fuel pump. Which keeps filling the carb full of gas which lasts for about 15 to 20 seconds.
When you let off the ignition, the pump is no longer powered by the starter, but now gets power through the oil pressure switch which closes when the oil pressure builds to over 3 psi.
This keeps the pump from running anytime the key is in the run position. It's a safety device.

 

[Dennisjr13]

Re: Stalling Issues?

Ok thanks, I will check the oil pressure switch tomorrow and see what's up.

 

[Dennisjr13]

Re: Stalling Issues?

I pulled the wires off the oil pressure switch and saw some corrosion so I applied some electronics cleaner to the wires and the terminals. After hooking the switch back up the engine started fine and ran for 10-15 minutes before I shut it off.

Do you think I fixed the problem or do you think that the switch has been failing intermittently?

 

[180shabah]

Re: Stalling Issues?

I think you found your problem, but spray cleaner is not the answer. Clean the terminals with abrasives, then use dielectric grease to to help prevent further corrosion.

 

[searay3]

Re: Stalling Issues?

Put a vom on the oil pressure switch testing resistance (Ohms). Crank the engine and watch the guage. should go from infinite resistance to 2 or 3 ohms once the switch closes. If it stays infinite (open), the switch is bad...

 

[anzomcik]

Re: Stalling Issues?

Hi, I do not want to make it seem like i am hijacking this post but i am a little confused, heres why

I bought a 2000 crestliner 2050 with 4.3 mercruiser alpha 1 gen2, when i test drove the boat i noticed the oil pressure gauge was not working. Sales man said it was easy fix... i got the boat late last season and put it right away to storage, last weekend i put the muffs on it, started and ran good. i did some looking and found the blue wire from the oil pressure send was not connected, so i connected it, wow i got oil pressure on my gauge. i took the boat out today and it started then shut off after a 27 secounds ( i started it like at least 20 times stalled about the sameevery time) i kept thinking it needed the stink blow out... got the boat home. any way now i read this,

My question is did my blue wire on the end stud of the oil pressure sender have anything to do with that? Or am i confused enough not to know what i am talking about. None the less my problem is a clone of what Dennisjr13 has wrote.