Hydraulic Fluid Leak - what am I looking at here??

[NatedoggAZ]

Hey all -

Need some help with a diagnosis here - I am totally lost on what the heck is going on here...

So - I replaced my hydraulic manifold the other day - but didn't get a chance to add in the fluid and test it out.

Just yesterday - I went over to where it is stored and brought a few quarts of hydraulic fluid. I filled up the reservoir on the pump and cycled the outdrive up and down a few times. The pressure built up and the OD now stays up - previously it was tied up because there was no hydraulic pressure due to me removing the pump for overhaul...

Anyways - after I cycled the outdrive up and down a few times - I noticed that the fluid was still a little cloudy - so I may have to drain it again...

....but that is the least of my worries now...

After I though all was good and well - I noticed fluid coming out of the drain plug hole - as well as fluid coming from between the transom and the housing!!

I probably have at least a busted hydraulic line - but fluid coming out from the gimbal housing???

What exactly is going on here??

Thanks in advance for your help/support/comments:

 

[alldodge]

few quarts of hydraulic fluid

Should use 10W30 motor oil

After I though all was good and well - I noticed fluid coming out of the drain plug hole - as well as fluid coming from between the transom and the housing!!

I probably have at least a busted hydraulic line - but fluid coming out from the gimbal housing???

Agree, either a busted/cracked line or leaking threads. Best to leave the manifold loose and hanging to check for leaks after installing lines on manifold.

The leak between transom and housing is not good. Might have to replace the transom seal, but might be coming between manifold and transom assembly, or even Mercathode if you have one of those

 

[NatedoggAZ]

This is the hydraulic fluid I used for the trim pump:

I took off the anode and checked the manifold to see if it might be leaking from there - see the 2nd pic.
The leak does not appear to be coming from up above the manifold - appears to be fully coming from the transom seal .

How big of a job is a transom seal replacement if that's the case?

ND

 

[alldodge]

You want 10W30 motor oil, not 30W non-detergent



To change seal, need to remove motor and drive. Then unbolt transom plate and remove transom assembly from the transom.

 

[Bondo]

The leak does not appear to be coming from up above the manifold - appears to be fully coming from the transom seal .

Ayuh,.... The leak could be anywhere along the line,....

The oil would chase the line downhill, 'n appear in the same place,.....

 

[NatedoggAZ]

Urgh - well, that's some pretty bad news - having to pull the motor.... that's some major work...to replace probably a $10 or less part... I might as well replace everything if I have to do that. ... all the bellows and gimbal bearing...and whatever else usually gets replaced while you have access to it.

Guess I will be changing out that hydraulic fluid to 10w30 as well...

Crap... summer is just getting started and now I have to deal with this...

ND

 

[Bondo]

- having to pull the motor.... that's some major work...to replace probably a $10 or less part...

Ayuh,..... Why would you pull the motor,..??

Ya drop the manifold, 'n fish the line up through to the pump, on the end of the one yer changin' out,....

The pump don't care which oil ya run in it, so long as there ain't any water in it,.....
I've run 10W hyd. ATF, or motor oil,..... They don't care,.....
Should all be the same oil though,....

 

[alldodge]

So long as your certain it is coming between the hull and assembly, and not to make matters worst, but if that is where its coming from, then there is a strong possibility that the transom is soft. So long as the transom stays solid, it is very rare if the seal ever breaks.

 

[NatedoggAZ]

Bondo AllDodge Is there a way I can check to see if in fact that leak is coming from the transom seal?

I'll pull down the hydraulic manifold just in case - but I just installed that thing and I wrenched it on pretty good with a new manifold gasket - so I kinda find it hard to believe its already leaking from around the manifold...

Is it possible that cavity is filling up with the hydraulic oil - and with having nowhere to go - slips in between the housing and the transom as in the attached picture?

Thanks!

​​​​​​​ND

 

[alldodge]

Is it possible that cavity is filling up with the hydraulic oil - and with having nowhere to go - slips in between the housing and the transom as in the attached picture?

Yes its possible but if a little bit of oil can seep out, then a whole lot of water under pressure will come flowing in.

Dry the thing real good, then run it so its leaking, then start looking real close as to where its coming from. Taking the manifold off just opens a big whole but does not tell you where the original leak was

 

[NatedoggAZ]

OK - I need to know if I am FUBAR here or what...

Went down to the boat yard this weekend to try and find where the hydraulic leak is coming from.
So - its pretty evident I need to replace the hydraulic hoses...

BUT - here is the larger issue... That fluid that is leaking from the busted hose - is definitely coming from between the housing and the transom.

I had a buddy raise and lower the outdrive so I could see where it was leaking from. The ourdrive got lowered too much one time and it hit the ground and put a little pressure on it.

That's when I saw a small gap open up between the transom and the housing - and the hydraulic fluid poured out like a waterfall from between the transom through that gap at the bottom of the housing...

So - whats going on here? Do I just need to tighten up the housing with the 2 bolts on each side - or what else am I looking at...

Thanks all...

ND

 

[Grub54891]

Raise the drive all the way up, have a buddy stand on it and jump up and down. Watch the transom itself, of it flexes it's rotten. You can drill holes from the inside of the transom, down low and see what the shavings look like, if they are dark mush, not good. If they are light colored and solid, you should be ok.
Seal the holes with so epoxy if it looks good. Just do not drill through to the outside.

 

[Bt Doctur]

Without knowing what your working on makes it difficult. If you have anode bolts, there probably corroded away, newer housings have studs and that would mean a very, very hard impact to break the stubs or a very rotted transom

 

[NatedoggAZ]

I'm really hoping for busted bolts - although still maybe a PITA to fix.... may still have to pull the engine to put on a new transom seal?

It could be because the previous owner hit something hard like Bt Doctur mentions.

Here is a pic of the bottom outdrive fin that may have caused that?

 

[NatedoggAZ]

I guess I could reach down and see if those bolts are loose and can be tightened any first... and also then check the transom. I live in Arizona though - so its not going to be wet rotted due to our climate if the transom went bad...