Originally posted in a related thread here <br /><br />My problem relates to an old Mercruiser GM 3.0L 181 C.I.D. engine, with a Mercarb 2 Barrel Carburetor. I was suffering from real bogging problems accelerating from idle, so I bought a service kit, and attempted a do-it-yourself carb service. The bogging problem was easy to fix - the Accelerator Pump Shaft & Lever assembly had loosened off the Accelerator pump, causing a large amount of slack. This is fixed, and my 'hole shot' is now beautifully smooth, with no bogging & no hesitation. The engine is running smoothly, ticking over evenly, with no evidence that i've screwed up anything ;-)<br /><br />...However, I seem to have created a new problem! As people have described in the thread I linked to above, the problem occurs after stopping the engine when warm, then attempting to restart after waiting about 5-10 minutes (restarting immediately after stopping is fine).<br />When this problem occurs, the engine is comlpetely flooded, so much so that rather than coughing & spluttering (how I remember flooded engines sounding) it just turns over fast & smooth with no hint of any combustion at all. I don't know exaclty how long it takes to clear, but it's more than an hour. Coming back to the boat the next morning, it starts ' on the key' as if there were no problems at all..<br /><br />When I look down the barrels after turning off the engine from warm, I can see a steady leak of fuel dripping (at a rate of about one drip per second) from each branch of the venturi cluster at the end of the 'V' that is directly over each barrel of the carb. I can also see big puddles forming on the back of the throttle valves, and a fair amount of fuel around the flat surfaces of the body at the tops of the barrels. I can't see exactly where the fuel is coming from, but i'm fairly sure it's coming through the venturi cluster brass tubes, rather than leaking from the venturi cluster gasket.<br /><br />I've had this thing apart again a couple of times, but everything seems just fine, and i'm out of ideas! It would be great if I could get some pointers...<br /><br />I've got some specific questions also, based on other peoples advice in the previous thread:<br /><br />Q1: Where are the well plugs? Can I spot if they are leaking?<br /><br />Q2: I don't know enough about the carb to understand exactly how the fuel gets from the float bowl through to the venturi. I'm going to check (again) as follows:<br />1) Main metering Jets & Gaskets<br />2) Power valve assembly and gaskets<br />3) Venturi cluster main gasket & center screw fiber washer<br />But can anyone tell me if i've missed anywhere that might be repsponsible for fuel leaking through into the venturi cluster?<br /><br />Any Ideas or pointers VERY greatfully received! Oh yeah, and this is my first post here, so hi everyone!! I promise to come back and let you know what the final solution was, and i'm hoping it won't be "Buy a new carb!"<br /><br />BTW while I was searching, I found a full MerCarb service manual PDF online at http://www.boatfix.com/merc/Servmanl/13/13B5R2.PDF <br />responses quoting page numbers and diagram references would be even more helpful (if i'm not being TOO cheeky!)
