warm engine bad idle

goodtimesfishing

Petty Officer 3rd Class
Joined
Jan 8, 2011
Messages
84
I have a 88 50 hp force. When I start the engine cold it will start right up, barely need to turn the key and it is running and stays running. After it warms up and I stop to fish for a while it will start right up but if I don't get it in gear and increase rpms it will stall. Once I increase the rpms for any amount of time (even just a couple seconds) I can put it back in neutral and it will idle fine. It acts like the idle needs turned up, but if I do that then the cold start rpms are way to high. What does it sould like I need to do????? Other then that it runs good, will do 29-30mph(gps) in current(saltwater).
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,909
Re: warm engine bad idle

Have you tried increasing the idle mixture screw a tad and if the idle rpm goes too high then lower the idle screw? High idle rpm's are really detrimental to the clutch fingers during shifting gear.
 

fucawi

Banned
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May 18, 2011
Messages
1,039
Re: warm engine bad idle

are you pumping the primer before you start it ..sound like you are lacking fuel until the pump gets going ....
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,075
Re: warm engine bad idle

Start with the basics.Comp test and a spark test.
Check the fuel pump diaphram.Check for water in the fuel?Clean the carb and while it's off check the reeds.
Then at the top of this linc is a linc and sinc it will tell you how to set up the carb linkage.
Then the air screw.In till it just stops,then out 1 and 1/16 turn.After it's warm,turn it in till it just starts to buck,stutters ,stalls.Then out 1/2 turn.
The rpm's should be 750-800 in gear, motor warm.In the drive about 1100-1200rpm.
 

shakazulu

Seaman
Joined
May 16, 2011
Messages
67
Re: warm engine bad idle

jerryjerry when you say "turn" do you mean 180 degrees or 360 degrees ?
 

goodtimesfishing

Petty Officer 3rd Class
Joined
Jan 8, 2011
Messages
84
Re: warm engine bad idle

fucawi- I don't think you are suppose to pump primer for warm engine are you? When it is cold or warm it starts very very easy, but when warm the idle is low and wants to stall.

Jerry, I ordered a fuel pump kit and hope that is the problem. I read that this problem can happen with a bad diaphram, as the fuel will leak down into crankcase??? I have had a blackish/oily residue on the splashwell on the port side?? Also, I am not familiar with checking the reads...how do I do that?
 

fucawi

Banned
Joined
May 18, 2011
Messages
1,039
Re: warm engine bad idle

I always give the primer a pump hot or cold ....and what I am suggesting is for diagnostic purposed to confirm you have enough fuel in your carb bowl...I dont see the point in getting all the spanners out until you given it a quick squeeze ........and its reeds
 

goodtimesfishing

Petty Officer 3rd Class
Joined
Jan 8, 2011
Messages
84
Re: warm engine bad idle

I knew it was reeds, I don't know why I spelled it reads.....anyways how do I check them?? What do I look for??
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,075
Re: warm engine bad idle

Turn is 360.
Remove the carb and with a flash light look into the opening behind the carb.The reeds should be all about the same.Any cracked/broken,bent or missing,then you have a problem.
If you set for any length of time you might have to pump the ball again.Possible the fuel leaks back down.
Black oily residue.Could be unburned gas/oil comming from the carbs when you tilt it up after use.
 
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