87' Merc 20 - Fuel Problem

[HLongcrier]

Motor was running like a top and cranking on first pull all day. I reached my duck hole and shut her off. When I came back a couple of hours later, I pulled the string and she fired off fine. After about fifty yards, the motor choked out and she hasn't run since. I changed plugs and they seem to be fine. Traced all the fuel lines from tank to fuel pump and fuel is getting to the fuel pump, but it doesn't seem to be going anywhere from there. I changed the fuel pump (no pin holes or anything seemed to be wrong with the old one, but I changed anyway) and still same result. She fires on first pull when starter fluid sprayed in the carb, but will only run on the amount of fluid sprayed. I have a feeling cleaning the carb will be next step but just wondering if some other part that I'm ignorant to would contribute to the prob. I'm new to the forum and would welcome any advice. Motor did this to me last year but after shutting off for an hour or so it would run fine, like nothing was wrong. Thanks again.

 

[Harker]

Re: 87' Merc 20 - Fuel Problem

First off, never use starting fluid on a 2 stroke..put a little pre-mix gas in a small spray bottle and spritz it in the carb..if it starts, I would say your carb needs re built. Take it all apart and soak it in carb cleaner over night then blow out all the holes with compressed air and put the new carb parts and gaskets in it.

 

[JUSTINTIME]

Re: 87' Merc 20 - Fuel Problem

time to rebuild the carb
if u do not have a shop manual get one and red up on it

 

[HLongcrier]

Re: 87' Merc 20 - Fuel Problem

time to rebuild the carb
if u do not have a shop manual get one and red up on it

Thanks for the advice guys. I disassembled the carb and soaked all the parts in gas last night. Cleaned them with the air compressor sprayer today and reassembled with new gaskets and fuel pump diaphragm. The merc is back in business! . Hit 32 mph in my little 14' jon boat today. She is idling and running great. I still can't believe a carb job it is that easy. Thanks again for the advice and have a great weekend