Volvo Penta 4.3 gl-a stalls without throttle

[V0x]

Hello,

I am an AZ boater in the Phoenix area. Issue I am having is when the engine is cold when first starting up for the day it will stall when at neutral idle. I have to run it with some throttle for several minutes before it will eventually let me throttle back to idle neutral without stalling and then is generally fine for the day. Seems like from reading IAC valve could be the issue but I can't seem to find parts diagrams or info on IAC valve for this model engine Penta 4.3 gl-a. Let me know. Thanks so much.

 

[Backyardmech]

I belive the 4.3 gl series is carburated. There is not an IAC. I would check if the choke is operating correctly.

 

[V0x]

I am considering buying a rebuild kit and taking the carb out and cleaning and rebuilding to see if that may resolve the issue. Quasi beginner with this level of boat maintenance so I'll have to research how to troubleshoot choke.

 

[Backyardmech]

I am considering buying a rebuild kit and taking the carb out and cleaning and rebuilding to see if that may resolve the issue. Quasi beginner with this level of boat maintenance so I'll have to research how to troubleshoot choke.

Is the choke closed when you first srart it?

 

[V0x]

I typically will pump the throttle a handful of times then start it while having it on partial throttle. I know this is proper procedure for a cold start anyway, but it seems like it needs to run for a while with throttle before it will let me back it down to idle neutral without stalling.

I bought some carb cleaner and ordered a rebuild kit. Will try my hand at that and see if it resolves the issue.

I wonder if rebuilding and replacing the carb is plug and play or if it would then require some tuning. Any idea?

 

[Backyardmech]

I typically will pump the throttle a handful of times then start it while having it on partial throttle. I know this is proper procedure for a cold start anyway, but it seems like it needs to run for a while with throttle before it will let me back it down to idle neutral without stalling.

I bought some carb cleaner and ordered a rebuild kit. Will try my hand at that and see if it resolves the issue.

I wonder if rebuilding and replacing the carb is plug and play or if it would then require some tuning. Any idea?

I just replaced my Holly 2 barrel with an edelbrock 4 barrel. It hasnt gone great so far. If it runs well after it warms up it shouldnt need a rebuild. Is the choke flap closed before you start it cold? If you open it with your hand does it close itself or stay open?

 

[Lou C]

If the engine runs well and doesn’t stall at idle after warming up then you may not need to clean out and rebuild the carb. What you need to of is observe the choke system for proper operation. The Holley carb uses an electric heated choke. This requires that the choke spring inside the black cap has enough tension to close the choke and that the electric choke heater has a constant 12v source so it can open as the engine warms up. Also there is a vacuum operated linkage that opens the choke plate a fraction of an inch so the engine gets enough air to keep running after a cold start.
So:
Before a cold start the choke plate should fully or nearly fully close, open the throttle fully to allow it to snap shut then use the throttle to set fast idle (1500 rpm or so)
After the engine starts the vacuum operated linkage should pull it open a fraction of an inch
In about 5 min of run time the choke should fully open

Is that how yours operates?