View Full Version : carb service

10-07-2003, 09:02 AM
My questions are these:
1)I have a 2000 Boomerang with less than 100 hours. It runs well, pulls smoothly and hits top speed with little effort. I do however get a smell of gas from the exaust at idle. The idle is a little lumpy but not uncomfortably so. I tried shutting down the idle mixture screws but this has little effect on the idle speed or gas smell. I am guessing that fuel is leaking internally inside the carb causing it to run rich?
2) Assuming the carb does need a service/rebuild can I just remove the carb and send it to Holley or is it better to find someone local who can set the carb up on the boat? I have had no dealings yet with any Moomba or Holley people in the area (Toronto, Canada). The boat runs well and I hate to take a chance on getting it serviced by someone who is not fully familiar with the Holley marine setup.

10-07-2003, 08:30 PM
You should be able to take it to any ski boat dealer (Nautique, Mastercraft, Tige, etc....) They will know how to work on the Holley carb. I would think that most marinas will have technicians that will know holley, they go on allot of different boats, not just ski boats....

Mine was doing the same thing, running good but rich and fumes at ilde. I brought mine to the local Supra dealer and they cleaned the carb out (carb/choke cleaner) and adjusted the idle mixture screws. I tried to adjust them myself, like you did, but to no avail. What ever they did, it runs great now and i am happy. Only cost me $39, 1/2 hour labor and lake test.....

Good luck

Brian Raymond
10-11-2003, 11:39 PM
The #1 cause of a boat running rich at idle, is loose float bowl screws. These are the (4) 5/16 bolts that hold the primary and secondary bowls onto the carb. These bolts tend to loosen over time, due to the expanding and contracting from the heating and cooling down of the motor with the soft metal of the carb. This can cause the bolts to loosen, and cause unmetered fuel to bypass some gaskets. Try tightening them, then readjust your idle air-bleed screws, and idle. Rule of thumb is, turn the idle-air bleed screws in all the way, then, back out 2.5 turns on each side. These are located on the port and stbd side of the main metering plate, just behind the primary bowl. Your idle should be at 700-800rpm. in neut. and 650-700 in gear. If this does not help much, call your dealer for an appt. Hope this helps. Brian Raymond

10-13-2003, 10:42 PM
Thanks Brian. I prepared the boat for our long cold Winter last weekend. I will print this thread and add it to my list for the Spring.

08-04-2005, 01:59 PM
Had to adjust my idle air-bleed screws yesterday due to the carb running poorly at idle at 6200 feet. Have a 2003 Outback and wanted to share something.

On the '03 Carb, the idle air-bleed screws are hidden behind two brass caps used by ?indmar? to seal them off from adjustments. I had to punch a hole in the caps and lever them out to get at the air-bleed screws. However, adjusting them made all the difference in the world and it runs great now.

So, if you are looking for the air-bleed screws on the metering block and can't seem to find them, it's because they are hiding.

08-04-2005, 02:15 PM
yeah..capping those screws off has been s.o.p. for many years now. So what you did was what we all have to do to get at the s.o.b.'s. I've not had to adjust them, but I know what it takes to git-r-done:p