Mercury Optimax Power Tilt and Trim

[Waterman]

So my leaky PTT has reared it's ugly head once again!

Coming back from a short trip last week I noticed the trim wasn't holding when under way. I replaced the o rings in the PTT unit last year and did notice some putting around the surface of the main tilt cylinder, however replacing the o rings fixed the leak until now. (I didn't buy the merc o ring kit, just measured the old ones and ordered the correct size).

Whipped the unit off the engine yesterday and replaced the o rings once again. When I refitted and filled the unit it was clear the leak was still there.





















The last pic shows the damage on the main tilt cylinder.

Is this repairable/salvageable?
If it was machined to get a clean flat surface would it make any difference?

Or should I be on the look out for another PTT unit??

Any advice would be most welcome??

[Locozodiac]

Is the damage located inside part 1 as seen on parts list, if so, there's no spare cylinder sleeve shown to change worn one. Seems you'll need a new one. Is the same issue as when brake cylinder corrodes and starts loosing brake fluid.It´s a non repairable part.

Happy Boating

[GONE FISHING]

HELLO,Waterman.
THE "O" RINGS ARE THE THE SEAL TO ANY P/T SYSTIM,
MACHINEING THE SURFACE WOULD NOT HELP AT ALL.
I WOULD REBUILD THE UNIT WITH NEW "0"RINGS ,AND FILL WITH A STRAIGHT S A E 30 OIL.
IF IT IS STILL LEAKING S***.
I WOULD BE ABEL TO HELP YOU WITH PARTS.
IF I CAN BE OF HELP P/M ME OR 07974 716522.
REGARDS,
GONE FISHING.

[Waterman]

Thanks for the replies guys.

There is no problem with the o rings. What I believe is happening is the gland into which the o ring in the last pic sits is pitted and causing the PTT fluid to leak out around the o ring.

I've replaced the o rings twice now
But as soon as I fill the system it starts to leak.

[GONE FISHING]

Hi.Waterman.
IF ITS OF USE TO YOU I HAVE 2 BRAND NEW P/T UNITS MERCURY Pt No,
99659A47. ONE IS COMPLETE IN ITS BOX.
THE OTHER ONE IS COMPLETE MINUS, THT MAIN PISTON.
REGARDS
GONE FISHING.

[Jizm]

Got a second hand one available if needed.