96 Maxum 17R MerCruiser 3.0 LX starting isues

[Stalefish]

Good morning everyone. I've done some research online and I'm just not finding the answers I need so I'm reaching out to other Maxum owners for help. Here's the situation (which I feel is a common issue):

Long story short, my 96 Maxum 17R with the 3.0 MerCruiser LX motor (inboard/outboard) runs fantastic. Never had any major issues in the 7 years I've owned it (knock on wood). The issue is after running for 15-20 min and I shut it off and we just chill out and float for any duration of time that exceeds 5 min, it takes FOREVER to get it started again. This issue is the bane of my existence with this boat. I do have a dual battery system, and switching to both batteries tends to help it get started again (2nd battery is a smaller House Battery).

An experiment I’ve done is to replicate this issue out of the water, with muffs attached to the lower end. I let it run for 15 min, some throttle, some idle. Then shut it off. Waited another 15 min and it starts up with maybe one/two throttle pumps (which never happens when we're out on the water). My theory is that with the muffs on, water is being forced into the lower end, whereas sitting static in the lake, not so much. Is this a logical issue?

What are the possible culprits I can begin evaluating to resolve this dilemma? My initial thoughts are a lack of battery power (but both are 100% when I go out), fuel pump, lower end issue, or temperature?

I realize this is a shot in the dark, but I’m hoping there’s other boaters that have experienced this exact issue and can share their remedy with me. My dream setup, for every boat owner as well I guess, is that I can turn the key and she fires right up.

Thanks for the assistance.

[mmwjr]

I suspect that when you shut the engine off the carburetor is dribbling some fuel thereby flood the engine. This can be verified by looking into the carburetor when the engine is shut off. A quicker way to restart a flooded engine is to open the throttle all the way up to let the maximum air in when starting. The final solution is to rebuild the carburetor.

[shrew]

Originally Posted by Stalefish

The issue is after running for 15-20 min and I shut it off and we just chill out and float for any duration of time that exceeds 5 min, it takes FOREVER to get it started again. This issue is the bane of my existence with this boat.

......Waited another 15 min and it starts up with maybe one/two throttle pumps (which never happens when we're out on the water).

After 15 min. I wouldn't expect it to need ANY throttle pumps.

Here was my Mercruiser starting sequence when I had a 454 with a carb.

1) Turn key to Aux.

2) Put shifter in neutral (throttle only) and give it 3-4 (usually 3) full pumps.

3) While in neutral bring the shifter to the FWD detenser.

4) Advance key to start while simultaneously (and very slowly) advancing the neutral throttle.

5) Once engine starts, pull throttle back to center.

This worked EVERY TIME.

[geoffm70]

my '94 3200 has 350s with carbs and Shew's startup is also how these start.