Need identification of two screws

[opie]

I am trying to get ready for the first splash of 2024 for my 1999 Mac X.

Yesterday I replaced both control cables. I dropped the lower unit to check the water pump impeller. I removed the internal flywheel cover and checked the Honda BF50A belt and put in a new thermostat. I changed oil and filter. I put in new spark plugs.

During all that, especially taking apart the control head, I threw all the screws, washers, pins, bolts, nuts, etc. into a small box. Also, I completely removed the control head even though I did not need to. (My bad)

All went well, but I took no pictures during my work. After all the work was done I found a pair of stainless steel screws left over . I have tried to identify them and so far have no idea where they go.

Any help would be appreciated.

Thanks

Opie

[leefrankpierce]

My MacX has boots that cover the holes where the cables go into the hull. Screws kinda look like those.

[opie]

Lee,
I won’t be back to the boat for a few days but thank you for that observation!

Indeed, I removed the boot from the cables and fuel and power lines at the transom. And while I replaced the boot afterwards, I probably left out those two screws.

99% sure you are correct bc the threads are NOT machine threads. The thread is tapered to catch fiberglass most likely.


Thanks for solving my dilemma.

[OverEasy]

Hi Opie

They don’t look like machine screws (too coarse a thread)…
They don’t look like sheet metal screws either (no taper, no lead-in point or self tapping features)….
So given the style of thread (uniform coarse thread without taper and a constant minor diameter) they could most likely go into a plastic component or housing.

They are relatively short too… so whatever they go through to hold on (like a cover maybe?) isn’t going to be very thick.
Typically “a designed for” fastener will allow for at least 3 threads (or more) of engagement into the base component.
Judging from the photo one would be looking for a flange or cover thickness of 8 to 10 mm or less.

Now given that nothing is a given when it comes to boats and people this is just an observational opinion.
People do/use what they want with what they have available.

Hope that helps narrow things down some for you…

Best Regards,
Over Easy

[tomradams]

These look like Thread-Forming Screws similar to this https://www.mcmaster.com/product/99461A207. They are used for screwing into plastic, and work well for fiberglass.

[opie]

Thanks Tom, Lee and Overeasy,

Indeed, the screws were left off the rubber boot covering the exit hole of the new cables.

What a great forum you have here!