New member - with a carburetor question

VIP

Cadet
Joined
Aug 21, 2005
Messages
6
I just signed up...great site. :) <br /><br />I have a 2000 Merc 25hp 4-stroke. I was having acceleration problems so after replacing the gas, checking the fuel lines and replacing the fuel filter I decided to look at the carburetor. I'd never taken one apart before but I decided to try. I found the rubber cap (over a metal rod) was torn and rubber was getting inside the carb. <br /><br />I disassembled the carb and removed the rubber pieces, replaced the cap and put it back together (correctly I hope). I put the carb back on the engine but now I can't get it to start at idle. :confused: If I throttle up it will start and seems to run OK but as soon as I try to go to idle it will stall. <br /><br />Any ideas or maybe I reassembled it wrong? Anyone point me to detailed pictures? I have the Merc service manual but the carb pictures are not very detailed.<br /><br />Thanks, Val.
 

yater

Petty Officer 3rd Class
Joined
Jun 12, 2005
Messages
79
Re: New member - with a carburetor question

It sounds like a clogged pilot jet to me. Did you make sure your jets were clear before putting the carb back together? The motor runs on the pilot jet at idle and switches to the main jet under throttle. I would check that first. I'm sure a merc expert will be along shortly and tell you where to find a schematic of your carb
 

VIP

Cadet
Joined
Aug 21, 2005
Messages
6
Re: New member - with a carburetor question

Thanks yater. The jets looked clean but I did not actually clean them with a carb cleaner. What should I use? I found disassembly and reassembly instructions in a Merc Service manual but it does not mention anything about adjusting or calibrating the jets. Do I need to do anything like that or can I just clean them and put them back?
 

andy6374

Lieutenant Commander
Joined
Aug 4, 2005
Messages
1,617
Re: New member - with a carburetor question

When disassembling and cleaning the carbs, you should soak all carb parts (except the plastic parts on throttle linkage) in carb cleaner. Napa or any other good automotive parts/service (Autozone..) will sell carb cleaner you can buy by the gallon. Let the parts soak for ~3-5 minutes, rinse with water, then completely dry them with compressed air. <br /><br />This will guarrentee you clean carbs<br /><br />You will need a new set of gaskets for reassembly.<br /><br />-andy
 

Coolmaker

Petty Officer 2nd Class
Joined
Mar 15, 2005
Messages
134
Re: New member - with a carburetor question

Make sure to use compressed air to blow out all passages (air and gas)after soaking the carbs...
 
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