1998 Force 120 HP Help

buddyt396

Cadet
Joined
Apr 6, 2015
Messages
8
I have a 1998 Force 120hp I bought new and have had very good service with it over the years. I recently had a problem with it not taking the fuel or something when you take off. (Won't plane off). It does it worst after you have run it a few minutes. Fuel line is good and ball stays hard. I noticed it has gas dripping out the front of the top carb while idling. Cleaned the carbs and replaced needles. Cleaned fairly new plugs. Went to river to fish and it's still doing the same thing
 

titaniumneck

Petty Officer 1st Class
Joined
Apr 11, 2016
Messages
209
I'm not going to say I'm a professional, but I have worked on plenty motors, so I will try to help. First off, what do you mean by the "not taking fuel or something"? Now, I have been told by some good guys on this site about a 75 EVINRUDE doing the same thing with the carb" spitting gas". Is the gas coming out of the carburetor throat, or the low pressure port? The EVINRUDE was spitting out of the low pressure port, which they said was normal for an older engine like this one, and the carburetors cover had a fuel recovery hose at the bottom of the carburetors cover housing. But can you please elaborate on the problem with the acceleration of the motor. I have worked on various outboards over the last 30 years.
 

roscoe

Supreme Mariner
Joined
Oct 30, 2002
Messages
21,657
Does the motor eventually get up to speed and wide open throttle?

I suggest starting by checking the compression and spark on each plug.

There are several possible causes.
Bent or broken reed valve is one.

Have you ever had the fuel pump rebuilt?
If nothing else, it is good preventive maintenance.
The diaphram in the pump tends to deteriorate over time, and faster if you use gas containing ethanol.
When this happens, little holes or tears develop, and it allows gas to leak through the back of the pump, into the block.
This causes a flooded condition, and the engine will bog and not reach full rpm.
Fuel pump rebuild kit is under $20.
 

buddyt396

Cadet
Joined
Apr 6, 2015
Messages
8
I'm not going to say I'm a professional, but I have worked on plenty motors, so I will try to help. First off, what do you mean by the "not taking fuel or something"? Now, I have been told by some good guys on this site about a 75 EVINRUDE doing the same thing with the carb" spitting gas". Is the gas coming out of the carburetor throat, or the low pressure port? The EVINRUDE was spitting out of the low pressure port, which they said was normal for an older engine like this one, and the carburetors cover had a fuel recovery hose at the bottom of the carburetors cover housing. But can you please elaborate on the problem with the acceleration of the motor. I have worked on various outboards over the last 30 years.[/QUOTE
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
17,923
Spitting or dripping out the carb on any outboard is NOT normal.
Do what Roscoe suggested after you check the overheat system.
​Possible it's getting hot??

​The Force doesn't have a system to shut down an overheating motor.

Compression,spark test.
Then remove and check the carbs for dirt? Replace that white filter with a see thru one.
G-2 G-3 G-12 Fram..
While they are off check the reeds.
The later years Forces had a problem with the reeds and you might be experiencing that?

Ethanol can hurt the inside of your hose.
It can melt or delaminate the rubber casing the filter to clog.

Post the results of your tests.
 

titaniumneck

Petty Officer 1st Class
Joined
Apr 11, 2016
Messages
209
I'm sorry Mr. Jerryjerry05, but I was to o this site that the low pressure idle adjustment screws with the hole in them on a 1985 EVINRUDE will spit a little gas from them after time, this answer came after I asked if I could change the factory screws with hole to s/s screws with no holes. I was advised but high ranking officials on this site not to change screws, that the carburetor cover was designed to account for this and had a pickup tube for excess gas. I cannot work with contradicting responses.
Now I will still ask if the gas is coming out of the carburetors throat. And more information on the symptoms of the hole shot problem. The more information you can give, the more accurate the response, and the minimal chasing ghost.
 

buddyt396

Cadet
Joined
Apr 6, 2015
Messages
8
I think I might have found the problem. I think I have some bad or cracked reeds behind the top Carb. Can these reeds be replaced with Carbon Fiber? Do I have to replace plates or can I just replace the reeds?
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
17,923
You can replace the reeds with carbon fiber.
I understand they sell a product called Boyensen Reeds.
Look them up.

The OEM is available from a few parts places.
E-bay has them from $30
 
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