View Full Version : stuck lower unit screw
bobber_boy
06-08-2006, 06:45 PM
Hello
I am trying to replace the lower unit oil on a 2005 Yamaha F150, brand new. I have done this many times on other engines but I can't get the drain screw to come loose...I can't put too much pressure on it without damaging the screw...so does anyone have any suggestions? I've tried hitting it w/ a hammer to break it loose and of course no worky :smash: :whazzup:
Impact wrench should bust it loose.
namu mac
06-08-2006, 07:22 PM
I had the same problem with both my 150's. I used a square shaft large screwdriver leaned hard on it and put a wrench on the shaft of the screwdriver the came loose.
I had the same problem with both my 150's. I used a square shaft large screwdriver leaned hard on it and put a wrench on the shaft of the screwdriver the came loose.
:yeahthat:
Chrome Bumper
06-08-2006, 09:25 PM
Don't forget the anti seize when you install it. The marine pros we use like the permatex? copper flavor, the silver is too gritty... They make those screwdrivers you hit with a hammer to pop it out. Or call in a pro to use some heat. Did you soak it with so good penetrating oil? Go slow so ya don't make a small problem big. Have you gone to ace hardware and got the biggest square shaft screwdriver they got yet that fits the slot perfectly? Brand new screw drivers with sharp edges work bettter than worn ones ya know. But those impact crewdrivers that ya whack with a hammer for about a 1/16th turn are the schizzle. I think they have a robot torque that stuff down, or maybe hired the trunck monkey to install them.
Spoiled Daddy
06-09-2006, 04:58 AM
I had that problem on an Mercury. I finally got the screw out, but damaged the head in doing so. Used a large screw driver and had a buddy tap it with a plastic mallet several times before it would break loose. If you damage the screw, I would suggest going to your Yami dealer and getting a replacement. It will make changing the fluids easier next time.
Just my .02
the Spoiled Daddy
bigredapes
06-09-2006, 07:48 AM
Copper based anti-seize? I thought that was a no-no on aluminium, and I thought all those lower units were aluminium. Idea was that copper and aluminium don't mix and cause the al to corrode.
What gives?
bobber_boy
06-09-2006, 09:13 AM
Thanks for the suggestions, I finally got it out!
thanks again
BB
patman00
06-09-2006, 10:12 AM
Copper based anti-seize? I thought that was a no-no on aluminium, and I thought all those lower units were aluminium. Idea was that copper and aluminium don't mix and cause the al to corrode.
What gives?
Anybody know the answer to this? I'd like to know also. Thanks,
The Salamander Hammer :whazzup:
Chrome Bumper
06-09-2006, 10:43 AM
I will retract that recommendation. We are working mostly with bronze, stainless and steel. It really helped the stainless from galling to itself and other metals though and for steel on steel it really works good. Aluminum may be an exception.