Cannot remove gearbox flat screws on Johnson 1972 4HP outboard

[mircearstan]

Newbie here, profuse apologies for this request but after 1 week of struggle I'm a bit desperate...

Trying to service the water pump on a 1972 Johnson 4HP outboard and everything went fine until I had to remove to flat screws on top of the gearbox to reach the water pump (see photo). I tried *everything*, regular flat screwdriver, power screwdriver, impact driver, the screws just won't budge The main problem is the "flat" aspect of the screws, there is really nothing I can figure out to do to keep the tip from slipping when I apply force. This should be a common issue for these lower units so I hope someone has a ready smart solution that I didn't think of.

In any case, if I get these off I'll make sure to use a different kind screws when I put it back. Thanks a lot!!!

 

[racerone]

There are various ways.-----Grind the head off.----Remove pump housing and impeller.-----Heat the housing and use vice grip to remove screws.----Impact screwdriver can also be used.-----I would grind the heads off.

 

[Crosbyman]

1/4 inch impact screw /nut driver try deepening the slot a bit with a hacksaw blade (not to much) before impacting

try to screw in a bolt just a tad to see if the thing moves forward .... then unscrew it

try shock freezing the bolt head 10-15 seconds with keyboard air blaster can (dollar store) held upside down

very important.... use proper sized flat blade on any screw/bolt head


but....grinding the head off will allow you to soak the threads with wd-40 or similar lubricants (Dupont snowblower silicone spray does wonders)

 

[mircearstan]

I was hoping for some magic but I guess good old elbow grease will do. I am still surprised that with so many of these motors around there are still such basic issues that linger. Anything other than a flat screw would have likely not caused this issue...

 

[oldboat1]

Big dog screwdriver (biggest one in your toolbox or your neighbor's). Visegrip clamped near the blade. Bear down hard vertically and use the vise grip as a lever to turn counterclockwise.

 

[racerone]

Back in the day the folks had to work hard to earn the money to buy a new outboard motor.-------They were expensive compared to today !!----Folks knew that you had to look at the impeller every 5 years or so.-----Today folks are much different.-----Never see the hood up at the gas station to check the oil !!----Run the outboard motor till it goes --" BOOM "

 

[werewolf]

if the screws dont turn i use a small plumbers torch and heat the screw head and soak it with gm heat valve spray, that stuff will loosen bad rusted parts , small amount of heat and it pulls the spray in like a vaccum

 

[racerone]

Heat the housing. where screw threads are.----No need to heat the screw.