1988 Force 125 Idle Mixture Adjustment****FIXED****

Justinde

Justinde

Chief Petty Officer
Joined
Dec 11, 2010
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431
Hi All

My top carb idle mixture screw does not make a licking difference to the boat- it runs the same screwed all the way in, or 7 turns out. The lower carb mixture adjustment works. I have taken out the needle/screw, cleaned and inspected and put it back, with no change. The carb is a little ' leaky', but it looks from reading some threads that this is mostly normal. The engine idles well, but I just wondered where I should look to try and fix this- maybe a fuel blockage but where to I begin to look.

Any ideas greatly appreciated. :)

Cheers
 
S

steveclv

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Re: 1988 Force 125 Idle Mixture Adjustment

Re: 1988 Force 125 Idle Mixture Adjustment

Yep, your float is out of adjustment, stuck or has sprung a leak and the top carb is flooded. Hence the idle valve having no effect and the leaking fuel.

It may also be the needle valve that is leaking.
 
Justinde

Justinde

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Messages
431
Re: 1988 Force 125 Idle Mixture Adjustment

Re: 1988 Force 125 Idle Mixture Adjustment

I'm going with float adjustment. I have the Clymers, but anyone have a rough idea as to how long and complicated this is to do?
 
jerryjerry05

jerryjerry05

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Re: 1988 Force 125 Idle Mixture Adjustment

Re: 1988 Force 125 Idle Mixture Adjustment

Simple as turning the carb upside down.Get the factory directions.5 min.J
 
Justinde

Justinde

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Re: 1988 Force 125 Idle Mixture Adjustment

Re: 1988 Force 125 Idle Mixture Adjustment

Sorry to sound dumb- turning carb upside down I envisage removing carb/linkages/fuel lines etc. ??
 
Justinde

Justinde

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Re: 1988 Force 125 Idle Mixture Adjustment

Re: 1988 Force 125 Idle Mixture Adjustment

Having saved literally thousands of dollars, the last little bit I don't want to stuff up is the mixtures and timing. I am thinking I might bow out here and pass it on to a mechanic who I found, that knows a lot about these engines. Last thing I want is for it to run too lean, and pop a piston, or, too rich and keep fouling plugs. I am happy with what I have done thus far, but I feel that the timing and carbs are out of my scope of ability. I tried today, but it still has a miss in it. Idles great for ages, then a small miss. Rev it up, it backfires, has a small miss, then revs freely. I don't want to stuff it up- so, over to the mech and see what happens!!
 
S

steveclv

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Messages
242
Re: 1988 Force 125 Idle Mixture Adjustment

Re: 1988 Force 125 Idle Mixture Adjustment

The timing is the easiest thing to do - just get yourself a cheap timing light from the auto parts store (or cheaper on eBay)

The carbs are so simple you can't screw them up unless you start fiddling with jets and you don't need to - there's only two linkages and two nuts and it's in your hands. Turn upside down and remove the bowl nut and there's the float and needle valve.

Mechanic will charge you $250 to do what you can do in an hour. You might as well learn how to do it.

If that top carb is flooding then you'll not get it running right - chances are very high that the timing is spot on - they don't change like a car with a distributor does.
 
Justinde

Justinde

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Messages
431
Re: 1988 Force 125 Idle Mixture Adjustment

Re: 1988 Force 125 Idle Mixture Adjustment

Thanks Steve


My 1988 Force has had the older ignition retrofitted to it- so I have in a way what looks to me like a distributor! I'll do the float- but from there can I completely stuff up the mixture?
 
jerryjerry05

jerryjerry05

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Re: 1988 Force 125 Idle Mixture Adjustment

Re: 1988 Force 125 Idle Mixture Adjustment

Picture 002.jpgThe linkage and all has to come off.There is a sticky at the top of the page for linc and sinc when you take it apart.
First do a compression test.Then check the reeds while the carb is off.
Hope you can see the pic.It's real easy to adjust thje float.
I wouldn't bet that's the problem.J
 
Justinde

Justinde

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Dec 11, 2010
Messages
431
Re: 1988 Force 125 Idle Mixture Adjustment

Re: 1988 Force 125 Idle Mixture Adjustment

HI All

GREAT SUCCESS!!! I adjusted the float level- it was definately out. I inspected and cleaned it anyways, put it all back together, and now it purrs like a cat ( or Force 125). The idle mixture adjustment works a treat on both top & bottom carbies, so now for a link & sync.

When I first joined I was very green behind the ears- now I have the confidence to do most work on the outboard. I dont want to ruin and speak to soon- the link & sync will be the telling factor as to weather or not all is well, but my guess is that it is pretty much 100%. Thank you to everyone who has helped me along the way!
 
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