1986 85 HP Force Lower Unit Drain Plug missing?????????

[fordpickup]

Ok, so I just bought this 1986 Bayliner Trohy Bass boat with an 85 HP Force. I've had it out on the lake once to try it out and it ran pretty good.

So I get it back home and figured I'd do a bit of maintenance since I can't be sure when anything's been done. My intention was to change the oil in the lower unit and the manual says there are 3 plugs (Pic from manual below) The problem is there is no lower drain plug. The skeg's been replaced, probably a few times, and I can see what looks like where there possibly could have been something but the weld went over. All I see is a small hole the size of a pencil lead, and what behind the hole is counter sunk into the oval about 1/32" so I can't really tell if it was once a drain plug, but even if so it"s way too small. Do I try drilling it? I must admit it scares me a bit to try that...

So I'm stumped on what to do now. Is there another way to change the oil? There's the pivot screw that the manual says not to touch, but could I drain the oil from here?

 

[foodfisher]

Re: 1986 85 HP Force Lower Unit Drain Plug missing?????????

Only down to the the level of the screw. Screw is a good description of the possibilities if you do. Solve the ? of what you've got going on w/the drain plug. Pic?

 

[jerryjerry05]

Re: 1986 85 HP Force Lower Unit Drain Plug missing?????????


Drain plug on the very bottom.
Allen head screw.Maybe covered with paint??
The slotted screw is for the shifter linkage.
DON"T TOUCH!!!!!!!!!!!VERY IMPORTANT!!!!!!!!

 

[jerryjerry05]

Re: 1986 85 HP Force Lower Unit Drain Plug missing?????????

Try scrapping the area around the hole.Wire brush?
Like I said before,DON"T TOUCH THE PIVOT PIN!!!!!
I had this problem with the allen head being stripped.
Until I fixed it(drill and easy out) I would remove the vent/fill screws.
Then pump oil in the fill till the dirty oil was replaced with fresh.
Or you can drop the drive and change the impeller and while it's off remove the screws and turn it upside down and drain.

 

[fordpickup]

Re: 1986 85 HP Force Lower Unit Drain Plug missing?????????

I'll try and scrape it back tomorrow and try to post a picture. The small hole I found was pretty much in the location where your 1st picture has it. I'm thinking whoever welded the skeg must have tacked over it a bit?? Hopefully I can dig it out.

If not I'll have to drop the drive. I've never done this before, is it hard to do?

 

[Jiggz]

Re: 1986 85 HP Force Lower Unit Drain Plug missing?????????

For last resort, you can also buy a small hand held pump with a small hose adapter to suck the old oil from the fill hole and then fill it on the same hole. Like this one.

http://www.amazon.com/Custom-Accessories-36670-Fluid-Quart/dp/B001DKQZ9Q/ref=pd_bxgy_hi_img_b

 

[jerryjerry05]

Re: 1986 85 HP Force Lower Unit Drain Plug missing?????????

Not hard to do.I see your in Canada so I guess it's probably never been in salt water.
The screws get gummed up and can be hard to remove.
If they don't come loose with regular hand tools then you might need some heat.
Remove the prop.
The exhaust snout.
Under the snout is a bolt.
Then the shift linkage in the front of the drive.
Then 6 bolts and it will drop down.

 

[Frank Acampora]

Re: 1986 85 HP Force Lower Unit Drain Plug missing?????????



If you can not get the drain plug out, remove the prop. Remove the anode behind the prop. Remove one of the bottom bolts holding in the bearing carrier and spool. Tilt the engine all the way in and with the vent open, most of the old oil will drain.

 

[fordpickup]

Re: 1986 85 HP Force Lower Unit Drain Plug missing?????????

Well I wasn't able to dig out the plug so I think I'll drop the LU and change the impeller along with the oil.
Thanks for the help guys.