1979 Force Drain Fill Plug

Hello, I purchased what I think is a 1979 140 Force(Rebuilt in 2003) and have now used it about 7 times and I am trying to change the lower unit oil. The problem is I can not get the drain/fill plug out and i'm very close to stripping it. I have tried WD40/ Dry Ice, Heat hammer etc.. No luck. Anyone have any ideas ?


Here is a picture:
http://img369.imageshack.us/img369/3453/img1071fh0.jpg

Before I use a bolt remover drill bit I want to make sure I can replace it(along with the vent seals). I don't have the serial or model number.. I found the part below but it shows no longer available.

PART: 22-47945
http://www.mercruiserparts.com/Show.../22.png&inbr=1827&bnbr=100&bdesc=GEAR+HOUSING

Any help is greatly apperciated

Lance

Re: 1979 Force Drain Fill Plug

That's a solid stainless 1/8 NPT slotted head plug. Same as the one usually found in the top of the head. Drain the lower unit by removing one or two of the bolts holding the spool (Behind the prop, behind the anode).
Then, heat the P I double ESS out of it with a propane torch and use an impact screwdriver. Nothing else will do and even then, you may strip the slot. However, because it is a solid plug, it is possible to re-slot it with a Dremel while it is still in. You can try drilling and using an easy-out but I have never had much luck that way, and if you break the easy-out, you are skunked. They are too hard to drill. The plug tends to corrode in tight so when you replace it, use teflon tape on it. If it just refuses to come out and you absolutely MUST drill it, then there is enough meat so you can re-tap to 1/4 NPT (or even 1/2 NPT only if absolutely necessary). If you do re-tap, don't go too deep These are tapered taps and plugs, and if you tap too far in, the plug will not seal.

If it is a Force, then it will be around 1983. Chrysler was still Chrysler in 1979 1/2 when they changed to the one piece lower unit. Strange--I don't remember Force ever making a 140 but around the changeover from Chrysler badging, anything was possible. They may have taken old stock and re-badged it. Look at the aluminum tag inside the lower cowl pan (support plate) below where the fuel line and control cables enter. If it is force, it will say US Marine and the model number will be 140XXXX With the first X being another digit and the next two being letters such as HB. They define the year.

Re: 1979 Force Drain Fill Plug

Good Luck! Those things can be tough!

Re: 1979 Force Drain Fill Plug

Frank, thanks for the advice that helps me out a lot and gives me some new hope.. I heated (probably not enough) with a small butane torch and used a regular hammer and screw driver before.. For some reason impact screw drivers are hard to find around here.. (Home Depot and Lowes did not carry them)..

This has become personal between me and that bolt..

I'll let you know how it goes...

Re: 1979 Force Drain Fill Plug

Sears

Re: 1979 Force Drain Fill Plug

Alright after some time I finally got this out by drilling through the bolt and pulling it out with a pair of plyers. I did strip the first couple of rows of threads, but there appears to be enough there to get a tight seal with a 3/8 bolt from home depot and rubber washers (I can't find a 3/8 actual drain fill plug online). My questions now are:

1. What's the best way to go about flushing the lower unit to ensure no metal made it into the gears?

2. For adding the new oil I have the Chrysler Outboards repair manual and it instructs to tilt the engine fully vertical and fill until oil comes out of the vent plug. I can raise the engine mostly vertical, but not all the way so i can't seem to get enough oil in to have it come out of the vent.. Does anyone have any ideas on how to do this easily? How much oil is enough ?

I apperciate any help..

Re: 1979 Force Drain Fill Plug

Not horizontal vertical, the other vertical. Flywheel points to the sky and the skeg points to the ground. Replace the drain plug and remove both fill and vent. Fill through the fill hole until oil appears out the vent. This will take somewhere between 24 and 32 ounces. let engine sit for about 1/2 hour to let air rise, then top off oil and replace fill and vent plugs.

You should be able to get a fill or vent plug from the local Mercury dealer. You definitely can get one over at The Chrysler Crew.

However, be absolutely certain that you are getting a good seal. this portion of the gearcase gets significant water impact and it will force its way through a poor seal.

If you do used a fill/vent plug, since the gearcase is curved at this point, you MUST spotface a flat circle for the plug to seal against. It would be MUCH easier and a more positive seal to try to clean up the threads for 1/4 NPT or re-tap them to 3/8 NPT.