88' 25HP Mercury with some problems

[korykreisler]

The motor will not idle without the choke pulled out. I can get it going out on the water and push the choke in and it will run like a champ but as soon as I power down it will kill and I have to pull the choke to get it to run again. I have cleaned the carb but don't know what direction to take next.<br /><br />Any help?

 

[Coolmaker]

Re: 88' 25HP Mercury with some problems

Check the fuel pump and make sure the o-rings are good in the hose ends.

 

[ntoracn@yahoo.com]

Re: 88' 25HP Mercury with some problems

I am having the same issue with my 1986 20 hp. It turns out that my switchbox is bad and allowing on one cylinder to fire at low speeds. Pull the plugs and perform a spark check.

 

[korykreisler]

Re: 88' 25HP Mercury with some problems

I replaced the fuel line and that didn't help. I have already replaced the fuel pump, and I have checked for spark. It seems like it will idle fine without the choke for about 30 seconds then it dies and needs the choke from there on out. When I pump up the primer ball it seems to stay firm but not as firm as I initally pumped it, could this be a problem, should I check the float level? Maybe I should just cough up the $70 an hour and have the dealer take a look....

 

[ntoracn@yahoo.com]

Re: 88' 25HP Mercury with some problems

The primer ball will be soft after the engine runs, this is normal. ANY engine takes 4 things to run: gas, air, compression and spark. You are missing one or more of them. get a manual and figure out which one and fix it or take it in and have it fixxed.

 

[Bob H.]

Re: 88' 25HP Mercury with some problems

Check fuel pump (replace it, they're cheap), the diaphram may be stretched and not pumping like it should at low speeds. If that doesn't do it move on the to carb. Low speed circuit probably has some crud and the carb needs to be taken apart for a proper cleaning.