85 HP Force Running Rough at Idle

fishthebay

Petty Officer 2nd Class
Joined
Aug 17, 2001
Messages
180
Hi all. I did a few posts last month in regards to my 1987 85HP Force Outboard.<br /><br />Here is the trouble.> When first started (starts fine) it seems to idel kinda low and will miss on occasion. Also, sometimes has a tendacy to die out when first put in gear.<br /><br />Once you are on your way the thing runs great at low level, mid level and WOT. It runs fine just giving it a little gas, but idle is the problem. Again, I do notice a miss sometimes.<br /><br />These are things I have done-<br /><br />1) Decarb treatment<br />2) Fresh fuel/oil mix 50:1<br />3) Primer bulb is hard and no leaks in the fuel line.<br />4) Fuel filter screen clean.<br />5) New plugs after decarb.<br /><br />I also turned up the idle speed screw a turn. This seems to help a little, but still getting the miss and rough and sporadic idle.<br /><br />I can see the carb (rich/lean) adjustment screws, but the bottom carb would be virtually impossible to get to because the motor casing seems to be in the way to get a screwdriver down there.<br /><br />My plugs also seem to get wetness (gas/oil mix) on them after removing. Not a ton, but I don't know if they should be getting that.<br /><br />Any suggestions?<br /><br />Also, does this cause any harm to the motor to keep running it this way? It seems to go just fine once you get going.<br /><br />The idle also seems to be better once the boat has ran for a while and you are stopping to fish.<br /><br />Thanks in advance...
 

Solittle

Fleet Admiral
Joined
Apr 28, 2002
Messages
7,518
Re: 85 HP Force Running Rough at Idle

It will not hurt it to run that way. Go to red Search and enter "Rough Idle" and read to your hearts content.
 

sony2001

Chief Petty Officer
Joined
Mar 17, 2001
Messages
607
Re: 85 HP Force Running Rough at Idle

You MUST adjust the bottom carb mixture screw. 90 degree screw driver or 1/4" ratchet with screwdriver bit. Its idling on 2 out of 3. :cool:
 

fishthebay

Petty Officer 2nd Class
Joined
Aug 17, 2001
Messages
180
Re: 85 HP Force Running Rough at Idle

Thanks everyone. Sony - I didn't ajust any of the carbs at this point, but was stating if I did this the bottom was hard to get too.<br /><br />Today's update-<br /><br />Just got back from my marina. Started the boat this morning. It fired right up and ran strong pumping a lot of water for about a minute.<br /><br />After about a minute it started to slowly idle lower. A little spit and sputter, but then suddenly came back to life and was fine ever since.<br /><br />Ran about 6-7 minutes total. <br /><br />Also, what I noticed was that a lot of fuel deposits were in the water (not a good thing for the environment)<br /><br />It appeared these were coming out of the tell tale, which also acts as a secondary exhaust.<br /><br />I suspect I have a lot of carbon and unburned fuel buildup.<br /><br />Is it safe to do another decarb treatment???<br /><br />I did it a month ago and let it sit in the carbs for about 15 minutes before blowing it out at fast idle and WOT.<br /><br />Any more thoughts on this idle problem????<br /><br />Thanks everyone.
 

fishthebay

Petty Officer 2nd Class
Joined
Aug 17, 2001
Messages
180
Re: 85 HP Force Running Rough at Idle

Do you think Quicksilver Oil may cause this to carbon up? I mix exact everytime and shake well.
 
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