trim pump leak

[Teamgreen]

So Im going to bring up this old thread as it is now applicable to me. I have pump C in the diagram shown above by Don S.
It started leaking a few days ago , so I replaced the four O-rings on the bottom of the pump. Just used O-rings from the auto parts store.

So my fix didn't last long. It is now leaking again, and it seems to be pushing out oil when I raise the stern drive. Its almost like the stern drive is all the way up but the pump wants to keep going so it blows oil out that O-ring. Is there a way to limit how high the stern drive raises?

 

[Bondo]

Is there a way to limit how high the stern drive raises?

Ayuh,.... Welcome Aboard,...... Take yer finger off the up button,....

From the thread ya hy-jacked,....

Re: Leaky Tilt/Trim Reservoir on '87 Alpha One Mercruiser

Which pump do you have, A,B or C?

 

[Teamgreen]

hmmmm. thats a novel idea. Was thinking more about a limit switch when raising stern drive.

 

[Pete104]

You never said what you have but I bet you don't want to get involved with the trim limit switch that old.

 

[fishrdan]

If the O-rings were not the correct size (too thin?), they could have blown out easily, probably a jillion different sizes and never the right size handy that you need....

I picked up a couple different O-ring assortments kits at Harbor Freight that have a pretty good variety, just not the standard "red box", but metric and others that I can't remember. 4 boxes in total, I think...

I would think there is a pressure relief valve somewhere in the pump, might be hanging up and causing the blown seals too. You would have to find an exploded diagram to verify, or start disassembling the pump and hope something doesn't go flying across the room.

 

[achris]

hmmmm. thats a novel idea. Was thinking more about a limit switch when raising stern drive.

If you have an 'R' drive (1982) or later, it's actually possible with the current set up to adjust the limit switch so that it would cut off just at maximum UP, but you would lose the proper limit function. It would also mean not using the trailer switch (or disabling it).

However, go to your local friendly hydraulics shop and ask for 4 Viton 'O' rings, size '012'. Problem solved. (BTW, they are not 'cheap', initially. But when you consider they outlast Nitrile about 6 times, they are actually about half the price. )

And yes, when the pump loads up, release the button.

Chris.....

 

[Teamgreen]

Thanks all! And thanks for the exact part required achris.

 

[Teamgreen]

https://www.acklandsgrainger.com/en/product/O-RING-VITON-ETP-AS568A-012-PK-5/_/R-WWG3CRT3

I hope this is the right one!

 

[achris]

https://www.acklandsgrainger.com/en/product/O-RING-VITON-ETP-AS568A-012-PK-5/_/R-WWG3CRT3

I hope this is the right one!

Looks it to me.