[boarder1010]

Hello All. Sorry but I am going to reactivate this post once again as I am still not 100% satisfied with my boat. To recap - I am installed a new carb from Guaranteed Carburetors, new cap and rotor this year (original OEM Merc), spark plugs last year (NGK), did not change wires or check timing, installed the fuel pressure regulator and have the flooding problem under control. The boat starts perfect every time and runs great on the mains but when I need secondary (4bbl) it still bogs like perhaps it is lacking fuel or timing. I am sure it is not short on fuel as I have installed and tested the regulator and it is within spec for my carb according to Guaranteed Carbs. Also I still have the hard starting problem after shutting down and letting it sit for more than a couple minutes. It does not start any better or worse if I open the deck when I stop. It is definately partially flooded when I go to start it because if I go to full throttle when it won't start it fires almost immediately. If I don't do anything and just turn it over it will probably take 10-15 revolutions to fire up. I did not check to make sure I have the Thunderbolt ignition but it is a 95 barchetta with 4.3LX so perhaps someone will know what I have and confirm that I have electronic spark advance? If so why do I have a port on the distributor cap? What should I try next?

[wonsnam]

Hi
A couple of thoughts on your problem first it sounds as though your carb is still flooding a little, have your float level checked if it is just a touch high it will run OK under way but will allow excess fuel to over flow into the manifold when shut down not much will cause the restart problem you explained. The second problem of bogs when secondaries open was very common in the early spread bore carbs. the float chamber is a touch to small for the large amounts of fuel required at WOT re jetting may help there I would try a size or two larger and see what that does, timing may also help, make sure the accelerator pump is in good shape. I have had a couple of Mercarbs that were jetted to lean from the factory (poor throttle response, Ski Boats) Your plugs will tell you a lot if you read them, the color of the porcelain tells wonders.
Good luck
Wonsnam
Talai Z201

[WetWilly]

Hi boarder1010,

I would start by checking the chock and making sure it opens fully when the motor get warm. Another area to check is the fuel float and needle valve in the carb like wonsnam said. Also check the clear plastic tube from the pump to the carb for any signs of fuel in it. If you do see fuel inside of the tube, your fuel pump diaphragm is torn and gas is being sucked into the motor via this hose so it's time to replace the pump.

I guess I've been lucky, I've never had the heat related starting issues with my previous I/Os. Running the blower isn't going to really help cool the motor down as the blower system is designed to suck air from the bottom of the bilge as gasoline vapors are heavier than air so it tends to build up from the bottom. I would think opening your motor hatch would be a better way to cool the motor and carb.

WetWilly