ox66 trim and tilt

[Dr1532]

I have twins 02 250 0x66, the power trim and tilt seals sit in the water and every few yrs i have to change them from barnacles sticking to them. up until now never had a problem as I use a spanner wrench, i must have bugger the inside threads on one of them as the cap binds up when i was putting it in even though i had washed and suc out what was in there. it is what it is . does anyone know if there is a tap to clean it up ,my machinist did some calculations and came out with a 44.958 x1.5 thread pitch, only thing i an find is a 45mm x 1.5 inch tap. my options are buy the tap, work a new cap back and forth as it is about three turns before tight , or buy a used one . like said cannot believe I did this thanks

[fairdeal]

I do not know what the nominal thread is.

But if I measured the actual part at 44.958 mm, and the pitch gauge said 1.5
I would assume that its "45 x 1.5"

[DennisG01]

Agree. .04 mm is nada, zilch, nothing, zip. Get the 45x1.5 tap.

On another note... how come the engines sit so low?

Use some of this stuff next time... carefully on the threads so it doesn't contaminate the fluid - put it on the male threads, skipping the first two threads. Once the cap is on, put some more all around the seam. Mercury Perfect Seal. That stuff is amazing. I'm sure there are things similar, but I know for sure that this stuff is what it is.

[Dr1532]

I will go with the 45x1.5, the boat sits low in the water as it has a stepped hull, 26" with a bracket 241/2 degree deadrise, probally should have a jack plate ,I could go up one more bolt hole , then i would be off underneath

[99yam40]

jack plate sounds like a good idea.
that way you could raise it when moored to keep the barnicals from growing