TOPIC: Transom screws for 1960 Merc 300

I bought a 1960 Merc 300, and found that it must have fallen over while not on the boat at some point, because one of the transom screws is slightly bent.
So I can not screw it all the way in.
I am guessing that transom screws were not redesigned from year to year , and I'm also guessing the threads, and lengths are standard also?
So my question is:
what range of years and motor sizes used the same transom screws that will fit a 1960 Merc 300 ?
Thanks in advance for any replies.

I have a few.
They are used, and are not flawless.
Little nicks & dings in the black grips.
$20 + shipping.
If you don't have the required tool to install one, I will loan it to you.
Don't try and remove the bent one until we talk.
PM if interested.
doc

Actually, there are two different sizes of the threaded shank for an original 1960 Merc 300, and they would change depending on whether the clamp brackets are from a short shaft or long shaft model. As the difference in diameter is small, you will best want to accurately measure to ensure the correct replacement is obtained.

Regards,
Joe
www.fergusonpoolemarine.com
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WOW !
I guess its a good thing I asked ?
Special tools to un-screw a screw or take the clamp screw washer off ?
Slightly different sized diameters and threads between short shaft and long shaft transom clamp ?
Damn !
(Im going to vent here a bit)
Ive been a design/detailer most of my life. And I try to design stuff to make it ME€ proof.
You see, Im left handed and of Polish decent. If there is a wrong way to build stuff, I usually find that way !
So I have to reprocess everything in my brain, because Im backwards in a right handed world.
So I do my best in designing, to make sure I can put stuff together , frontwards, backwards right side up, or upside down, and it still works AND put it together with a plastic spoon. AKA ME€ proof
Apparently Mercury decided Lets mess with people so they fix anything ?
Kind of like putting together Harbor Freight tools where they ship 1-1/4 long bolts and 1-3/8 long bolts, And I get to the last step in those blurry a$$ crooked instructions that have been thru a copier 1000 times, and find out I put the long bolts where the short bolts go, and I have to take the whole damn thing apart again to put the correct bolt in the correct place ?
Ha-Ha-Ha !

Anyway, back to topic. I will get my calipers out to check the diameter of the screw, To make sure I let the good doctor know what I need ?
It may take a day or two because its still cold here and the motor is in the barn.

No special tool required to unscrew the 'screw', but once you have knocked off the washer with a punch & hammer, you might find that the end of the threads are mushroomed, and need to be filed off a bit to allow you to unthread it without damaging the female threads in the transom clamp.
doc

I just use a wiz wheel and cut them off when replacing them. ball pien hammer will mushroom the end for the washer.

Hi Chuck,
While I understand you thought, Mercury was doing extensive testing to ensure safety and durability if the outboard should strike an underwater object at speed. With the greater leverage a long shaft model has, they choose to use clamp brackets with greater length, machined for up-sized boat mounting bolts/washers/nuts, and the mentioned larger diameter thumb screw assemblies shared with higher horsepower models. I feel that it is like many other companies which "go to their part's bins" to make wanted/desired changes.


Regards,
Joe
www.fergusonpoolemarine.com
This email address is being protected from spambots. You need JavaScript enabled to view it.

There you go. That makes sense. That is why I'm a designer not an engineer.

I grew up in a high crime area in the 70’s. Some kids floated an old dry railroad tie out across our muddy river by the bridge. Floating flush with the water, my brother could not see it. Luckily we were cruising about 25mph instead of 48 with the ‘74 150 Merc on a checkmate. BAM - what a violent strike! Thanks to the motor and boat engineers, it all survived without breaking something. Glad they are engineering for the unknown. 3 kids laughing under the bridge at us. We didn’t find it funny. Plenty of refrigerators, bikes, furniture and even stolen cars dumped right there...nice to live far away from there and boat in nicer waters where people respect each other.