Force 125 88’ won’t run

Oillywater

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This might be a stupid question but when I removed the lower unit there was some water inside. Like in the cavities. Is this normal? Tried searching but closest I found was someone mentioned it but no one brought it up so seemed like it was ok but not confirmed so I just want to confirm it.
 

Oillywater

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https://forums.iboats.com/threads/step-by-step-impeller-change.229221/ This thread by the late Frank Acampora is about replacing the impeller and gives detailed instructions for removing the LU......it's in the stickies at the top of this forum....lots of good info in those threads.
I saw that it is very helpful. Anti seize.
This might be a stupid question but when I removed the lower unit there was some water inside. Like in the cavities. Is this normal? Tried searching but closest I found was someone mentioned it but no one brought it up so seemed like it was ok but not confirmed so I just want to confirm it.
 

topgun3690

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Water in there is normal. Not a problem.....water IN the gearbox itself is not good.
 

Oillywater

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Water in there is normal. Not a problem.....water IN the gearbox itself is not good.
Ok and I won’t know till I change the gear fluid right? Also what do you suggest I do to the motor. As In “tune up” terms. Gear fluid, sparks, carb cleaning. Anything else. I do need to change the prop the previous owners where hitting the rocks with the prop looks like the edges are grinded down. Was also thinking of adding a telltail
 

topgun3690

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Ok and I won’t know till I change the gear fluid right? Also what do you suggest I do to the motor. As In “tune up” terms. Gear fluid, sparks, carb cleaning. Anything else. I do need to change the prop the previous owners where hitting the rocks with the prop looks like the edges are grinded down. Was also thinking of adding a telltail
If the LU has been sitting for a while any water in the gearbox will settle to the bottom....when you remove the plug water may come out first. If the LU has been used recently, any water will be mixed in with the lube, and will look creamy or milky.....see what comes out when you drain it, post a pic if in doubt.
 

topgun3690

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You did a comp test and spark test.....jerry suggested replacing fuel pump diaphragm, transfer port gaskets, clean the carbs.....have you done all that yet? The prop.....is it bent or damaged? Aluminum or stainless steel? Running a bent prop can damage the gearbox over time. Guess you saw the stickie about adding a telltale.
 
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Oillywater

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You did a comp test and spark test.....jerry suggested replacing fuel pump diaphragm, transfer port gaskets, clean the carbs.....have you done all that yet? The prop.....is it bent or damaged? Aluminum or stainless steel? Running a bent prop can damage the gearbox over time. Guess you saw the stickie about adding a telltale.
I just got the fuel pump gasket today will change tomorrow. Still don’t even know if the motor will stay on haha. Was waiting for this gasket. Also got the one port gasket behind the fuel pump. Should I change all of them? I clean the carbs it doesn’t seem bent just grinded almost flat on the ends seems like steel not 100% will let you know tomorrow.
 

topgun3690

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I just got the fuel pump gasket today will change tomorrow. Still don’t even know if the motor will stay on haha. Was waiting for this gasket. Also got the one port gasket behind the fuel pump. Should I change all of them? I clean the carbs it doesn’t seem bent just grinded almost flat on the ends seems like steel not 100% will let you know tomorrow.
If you're going to replace the port cover gaskets best to do all of them. Then do the fuel pump. If your prop is SS it can be repaired but can be expensive. You could probably buy a new aluminum prop for a few more dollars compared to repairing a SS prop. I switched to aluminum mainly because it you hit something, it will bend or break the prop instead of damaging the LU....SS props are hard and if you hit something it can trash your LU. That is my opinion, others may disagree.....
 

Oillywater

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If you're going to replace the port cover gaskets best to do all of them. Then do the fuel pump. If your prop is SS it can be repaired but can be expensive. You could probably buy a new aluminum prop for a few more dollars compared to repairing a SS prop. I switched to aluminum mainly because it you hit something, it will bend or break the prop instead of damaging the LU....SS props are hard and if you hit something it can trash your LU. That is my opinion, others may disagree.....
Ok I’ll post In here about how the fuel pump goes and I’m with you with ss and alu makes sense to me. I’ll probably see to get a new one soon just wanna fish already lol
 

topgun3690

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Ok I’ll post In here about how the fuel pump goes and I’m with you with ss and alu makes sense to me. I’ll probably see to get a new one soon just wanna fish already lol
If your old prop isn't real bad, could use it as a spare, to get you back to the ramp.
 

Oillywater

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GASKET, FUEL PUMP

F438760
DIAPHRAGM, FUEL PUMP
F438747
change them.

GASKET, TRANSFER COVER

F40223 This gasket could be the problem.
4 of them. Cheaper on Ebay
"27-820500A3 Transfer Port Cover Gasket Kit Mercury Force 40-50HP Outboards"




Bad news:/ I changed the fuel pump gaskets the port cover gasket on the fuel pump. Changed impeller not that that matters I think. Also re did the spark test and everything was sparking at the same speed and seemed like a good speed for me. But still won’t start unless I put starting fluid and it only stay on for a sec or 2 then backfires and dies. I just want to go fishing:(. Please help
Also I might add it seems like some redid the timing it has some marks on the flywheel and some notes for timing in the manual
 
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Oillywater

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I pulled the fuel line to the carbs and they were all pressurized so they are getting fuel idk if they are when the motor is cranking but I just changed all that so I’d assume so. Did I **** somthing up in the carbs. I just took the idle screw all the way out. And sprayed carb cleaner took the bowl off. Sprayed down the middle since I couldn’t manage to get the jet screw off took float off and sprayed the float stop thing and even then the carbs are actually pretty clean.
 

topgun3690

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Oilly, you say you changed the fuel pump gasket.....did you put in a new diaphragm too? Does the primer bulb get hard when you squeeze it?
 

Oillywater

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Oilly, you say you changed the fuel pump gasket.....did you put in a new diaphragm too? Does the primer bulb get hard when you squeeze it?
Yup changed the gasket diaphragm the little cork gasket behind the 1 way valve in the pump the x looking gasket in the back and the port cover. It does get hard. I checked for gas coming out when pressing the bulb on the carb fuel lines and the fuel pump out line everything was good. I’m wondering why when I cranked it for the first time after disconnecting the magneto, while it was cranking gas would drip out the mouth/ opening of the carb then it started for about 4 second then backfired and ever since then no more gas out the mouth of the carbs. Has to be fuel related if it starts with starting fuel right? And thanks for your help and your patience with me haha
 

topgun3690

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When you had the carbs off did you check the floats to see if they were adjusted right? And how many turns out did you use on the low speed/idle screws?
 

Oillywater

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When you had the carbs off did you check the floats to see if they were adjusted right? And how many turns out did you use on the low speed/idle screws
I just took off the carbs to clean for the 3rd time. Noticed on the carb for the bottom the speed screw was worn(pic below) top carb was in very good condition. As for the floats I heard they are just supposed to be flat when u hold it upside down and I can see the plunger thing move with it up and down and don’t see much wear on it. But I don’t really now how to adjust them.
I honestly lost track of that halfway thru when I was trying to remember but I read in the manual to screw it all the way in then back out one turn and adjust from there. But I do remember they were backed out pretty far about like 10 turns or. soIMG_1003.jpegIMG_1004.jpeg
 

topgun3690

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Yes, floats should be level or even with the carb body when turned upside down.....10 turns out on the idle screws is waaay too much. Try 1 1/2 turns out from lightly seated. Sounds like this motor was in a non-running condition when you got it? There is no telling what the PO did to this thing before you got it. If the timing is way off it will not run even if you have spark. May have to do a complete Lync n Sync to get it right. There is a stickie by Frank A. about synchronizing the carbs and timing.
 

Oillywater

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Messages
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Yes, floats should be level or even with the carb body when turned upside down.....10 turns out on the idle screws is waaay too much. Try 1 1/2 turns out from lightly seated. Sounds like this motor was in a non-running condition when you got it? There is no telling what the PO did to this thing before you got it. If the timing is way off it will not run even if you have spark. May have to do a complete Lync n Sync to get it right. There is a stickie by Frank A. about synchronizing the carbs and timing.
Ya motor wouldn’t start but it also had a faulty ignition switch messing with the magneto. The carbs have to be timed? I thought that was only for when it’s running and you hit the throttle. Can I check the timing with a car timing gun. Could the timing of the engine be off. Also what did you think of the idle screw picture.
 
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