Force 125 1986, hole in front of lower unit weeping oil

[Radiodan]

Just bought this boat (1987 Bayliner with 1986 Force 125 1251x6b), had motor lowered to clean up a few little things, lube starter, add low unit oil thru fill hole until runs out vent. It took about 12 or so ounces to fill. After filling, it sat for three days in the lowered position and I did not see any oil leaking. After putting water muffs on and starting engine, let idle a few mins, and at idle put it in fwd, then rev, no problem with that, then shut it down. Tipped up motor to get ready to tow to lake and when tipped up, I then noticed a small round hole, about 1/8" diameter in the front of the lower unit (about 3 inches up from the bottom) started weeping gear oil. I used to have a 1984 Force 125 long ago and do not remember this. The hole is perfectly round, like it is supposed to be there but I doubt it is supposed to weep oil. The leaking gear oil thru this hole did not happen when I filled it and it just sat. It only happened after I put water muffs on and ran motor, then tipped up to transport. I try to limit the water pressure but still have flow. I do not turn on water full blast. When I lower the motor it still weeps oil and water out that hole. After about 10 minutes with motor lowered, no more leaking oil but water is dripping out that hole. Water also drips out the small holes near the lower unit bolts to upper unit
Is this hole normally there?
Why no oil leak when filled but now oil leaks when tipped up after running motor?
One other clue, seller said he just replaced impeller (I do not know if he put it in the water to use it after the replacement)

 

[las]

I don't know if the same, but I have several small holes in the ventilation plate venting the inside of the leg I guess.
If the gearbox is full and you trim it up, oil would leak out of the shift shaft seal and the main oil seal under the water pump if they are toast.
But if you have a hole below the ventilation plate in the gearbox itself, then it's bad!

 

[racerone]

Most motors have these drain holes.----Makes sure that cavities do not freeze in cold climates.----And yes the oil mixed with the gasoline can leak out of them at times.----Just normal 2 stroke operation !

 

[Radiodan]

Tnx very much for the responses, a bit more research and it appears that nice round 1/8" hole in the front of the lower unit is supposed to be there.
Update - After sitting for 2 hours, I opened lower unit drain plug and the lube that came out was very milky, so I definitely have some seal problem. However, when I trim the motor partially back up, the gear lube coming out that front small hole in the lower unit is pure golden brown just like when I put it in. Just talked to previous owner and he told me he never had the boat in the water after he replaced the impeller.
Is it possible or probable that Water pressure on water muffs created too much pressure and blew past seals? (I suppose, either way, I need to drop lower unit and replace seals?) Is there a good video on how to do this and check for whatever other seals and gaskets might be a problem? Are mid-late 80's Force 85 and 125 basically the same. Also, are 85 and 125 lower units interchangeable?

 

[las]

No muffs won't create that much pressure unless you have a 100% seal and high pressure in the tap, but I would say the seals are bad.
If you only ran on muffs and still got water in the box it's either the o-ring on the prop spool and / or driveshaft seal. These are the ones under pressure when on muffs.
And since you have oil coming from the top of the leg I would say the driveshaft and maybe even the shifter seals are bad too and likely the spool o-ring.
I would replace all lower seals, including prop shaft seal.

 

[Radiodan]

Tnx so much for your input, I really appreciate it!
If I consider the clue of the previous owner changed the impeller because the old one disintegrated, perhaps damaging the driveshaft seal when it broke into pieces or some error in replacement. When I get it down, I will replace all seals I can find. When done, I will report back here so others may benefit from this thread and the help offered.

 

[las]

Your welcome, and do let us know how it turns out.

 

[The Force power]

Is there a good video on how to do this and check for whatever other seals and gaskets might be a problem? Are mid-late 80's Force 85 and 125 basically the same. Also, are 85 and 125 lower units interchangeable?

Get a manual it will be your best investment ever!
google seal kits or check the shop on this site for a complete kit
as long as the both have two piece shafts then yes they are interchangeable

 

[jerryjerry05]

Don't listen to everyone who gives you feedback.
Some have no clue and just use the WAG system for diagnosis.
You need to remove the lower, drain the oil and do a pressure test before you go and do a reseal job on the lower unit.
When the lowers off, remove the pump and check and see if there's oil there under the wear plate.
The base of the pump is VERY fragile and can be broken easily.
Get a factory service manual. Clymer and Seloc cover some but nothing like the factory book.
(wag system= wild a## guess)

 

[las]

Don't listen to everyone who gives you feedback.
Some have no clue and just use the WAG system for diagnosis.
You need to remove the lower, drain the oil and do a pressure test before you go and do a reseal job on the lower unit.
When the lowers off, remove the pump and check and see if there's oil there under the wear plate.
The base of the pump is VERY fragile and can be broken easily.
Get a factory service manual. Clymer and Seloc cover some but nothing like the factory book.
(wag system= wild a## guess)

What's the point of this forum then?
And by the way I only use the BBD system, it's a system you adapt when you reach godlike level WAG operator.....

(BBD system = Big Brain Deduction)

 

[jerryjerry05]

The purpose of this forum is to get GOOD info not someone guessing on how to repair something.
It better to be thought a fool than to speak and remove all doubt.

There have been people on here that have cost the new posters a lot of $$
They mean well? but do more damage when they add something that isn't right.
Simple: if you don't know?? say nothing.

Example: fellow was having trouble with his motor, he was told "without a doubt it the stator" $200 spent when it was the flywheel magnet. That guy meant well, but shouldn't post. His experience came from owning 1 Force motor.
Mine and other poster come from years (35)of working on boats.

 

[las]

Ok and you decide what is good info then? I had a suspicion, but by now you certainly removed all doubts....

How arrogant do one have to be, to think they know more than someone they've never meet or know.
My experience comes from almost as many years working as a mechanic, owning several boats, over 100 cars, been driving gokarts and racing 2 stroke RC cars on a semi pro scale. I've worked on almost anything under the sun.

But I too know mechanics, that have worked as such for many years and think what they say are gospel. Full of themselves, not able to process thoughts outside what they learned 40 years ago in school, only accepting their own opinions and way of thinking and doing things.

Sorry to ruin your thread Radiodan, I hope you still get some valuable info out of it!

 

[Radiodan]

Hello again, these are the three manuals I have for my engine, 1986 Force 125, model 1251X6B
Left one is Force manual OB4130, 1984-1988 85/125
Middle manual is Force manual OB3874-1 covering 125 among others
Right one is Clymer manual B750, 3.5-140hp, 1966-1988
I believe I am in good shape as all three seem to cover my engine and two of them are factory. I trust this is what you guys had in mind?

 

[Radiodan]

I want to thank you fellows again for the help, I don’t have much experience with my motor as the 125 I had before with my older Bayliner required no work! I have wrenched “in the old days” on my ‘64 GTO’s and other muscle cars but that was late 70’s. All I had time for today was to drain milky oil out drain hole. I hope to remove lower unit on Sunday and let my eyeballs do a good visual inspection, then pressure test, but need some advice.
On the pressure test, Do you have a specific tool in mind? I really don’t want to buy a professional version since I will be limited to working on my own motor (hopefully rarely!) and don’t want to spend more than needed. I read elsewhere about a bicycle tire pump ( with attached gauge, I suppose).
Also, where to get the fitting with hole in center to screw into fill or vent hole that I can connect to air pump? I have seen the plastic cone type that can be pressed into the hole but will only hold pressure while I hold it in there, this will allow me to use only one hand while I hold the cone fitting to the hole. I would rather have a screw in fitting. What Am I looking for? Thread type? Ace hardware have this?

 

[jerryjerry05]

I use the compressor with an air nozzle.
Take the drive off, soapy water in a spray bottle.
TINY!!! bursts of air and spray the leak points.
Lok on Google for home made pressure testers.

 

[las]

A bicycle pump would be a great idea and that way you can safely increase pressure to around 10 psi and see if it leaks. Be careful not to blow your seals!
Maybe get one of those refill kits for gear oil and use that adapter for the thread.

 

[Radiodan]

OK, dropped lower unit today. Noticed the "driveshaft spline seal" near the top bushing of driveshaft missing and the (what I call the)"bellows" covering the shift shaft is damaged but I cannot even find a rubber "bellows" in any parts lists. I would imagine the seal below it is the important water keeper outer. Also, the "lower inlet water line seal" on the water pump housing looks like it probably is functional but could be replaced. Nothing else obvious to me visually. I will order a fitting from a fill kit to make my own pressure tester and report back. Here are some pics from todays work. If you fellows see something of note, let me know, With your help, I am sure I can get this done and my boat in the water!
EDIT --- Is it possible the driveshaft spline seal is stuck up inside where the driveshaft fits in to? 2nd to last picture.

 

[The Force power]

I want to thank you fellows again for the help, I don’t have much experience with my motor as the 125 I had before with my older Bayliner required no work! I have wrenched “in the old days” on my ‘64 GTO’s and other muscle cars but that was late 70’s. All I had time for today was to drain milky oil out drain hole. I hope to remove lower unit on Sunday and let my eyeballs do a good visual inspection, then pressure test, but need some advice.
On the pressure test, Do you have a specific tool in mind? I really don’t want to buy a professional version since I will be limited to working on my own motor (hopefully rarely!) and don’t want to spend more than needed. I read elsewhere about a bicycle tire pump ( with attached gauge, I suppose).
Also, where to get the fitting with hole in center to screw into fill or vent hole that I can connect to air pump? I have seen the plastic cone type that can be pressed into the hole but will only hold pressure while I hold it in there, this will allow me to use only one hand while I hold the cone fitting to the hole. I would rather have a screw in fitting. What Am I looking for? Thread type? Ace hardware have this?

I made mine out of fittings of old handpumps to fill the gear oil into the lower-units. one for pressurizing & one attached to a gauge RATED for low-pressures ONLY (for accuracy )

while pressurized (no need for more then 10 psi) turn drive & prop shaft move the shift-shaft up/down multiple time to ensure it holds the pressure in every situation.
IF....you can?? pull the LU in a vacuum and see if it holds Seals are funny that way; it can hold pressure at certain pressures & not a vacuum, resulting in water in the LU

 

[The Force power]

If you fellows see something of note, let me know, With your help, I am sure I can get this done and my boat in the water!
EDIT --- Is it possible the driveshaft spline seal is stuck up inside where the driveshaft fits in to? 2nd to last picture.

I don't understand why I see tread on the shift shaft?
The rubber seal could be stuck up in there as there with amount of grease showing although I cant really see it in the pic.

 

[Radiodan]

I made mine out of fittings of old handpumps to fill the gear oil into the lower-units. one for pressurizing & one attached to a gauge RATED for low-pressures ONLY (for accuracy )

while pressurized (no need for more then 10 psi) turn drive & prop shaft move the shift-shaft up/down multiple time to ensure it holds the pressure in every situation.
IF....you can?? pull the LU in a vacuum and see if it holds Seals are funny that way; it can hold pressure at certain pressures & not a vacuum, resulting in water in the LU

Harbor Freight has a vacuum/pressure tester for $65, I was just going to make my own pressure tester but if a vacuum is also of value, maybe I should just buy that kit?