Need advice on hydraulic fittings for Merc trim pump

LaRea

I'm looking for advice on hydraulic hose fittings for my Mercruiser trim pump hoses:

As built by Rinker in 2007, the hydraulic hoses from the trim pump to the outdrive had a 90 degree bend at the pump.  I'm installing new transom assemblies, and the hoses have a 45 degree bend.  Unfortunately, the hoses don't clear the steering gear.

The pump has 1/4" Parker ST Series quick-release fittings.  A male-to-female fitting with a 45 or 90 deg bend would work, but I can't find one.  Do I need to find a local outfitter and make custom adapters?  Surely somebody on this forum has tackled this problem.  

LaRea

I don't think I can bend the fittings.  There's only 2" between the fitting and the hose.

Aqua_Aura

Call around to some brake shops or if you have a hydraulic rigging company nearby that does equipment hydraulics. 

YYZRC

Could you relocate the trim pump slightly to port to get it out of the way of the steering?

Handymans342

NAPA or a hydraulic hose shop. They are just flare fitting thread. 

Handymans342

I have a shop here and they have shelves of fittings

Grahamu

I am not sure, will check tomorrow, but I think the other end of the hose has a 90 degree bend. If so is it possible to turn them around?.

Grahamu

You might also consider having your old hoses pressure tested and possibly using them.

aero3113

@Grahamu , I think he mentioned in the other post that the transom assembly would have to be removed to replace the lines. 

Grahamu

OK I did not see that, I'm installing mine tomorrow so I will see what that entails.

LaRea

Seems there is no such thing as male-to-female elbow in that quick-release fitting.  

I'm gonna try putting a 1/8" NPT elbow between the pump body and the quick-release.  The problem is that when I screw the elbow into the pump body, it might end up at some angle that I can't use.  But I'll try it.

I definitely can't reuse the old hoses.  One of them ruptured, which is the event that led me to replace the transom assemblies.  I could buy new ones, but as I said, that would be a huge amount of work.

Grahamu

You can also get them in 45 degree
Extruded 45° street elbow | Pipe fittings - brass | Fairview (fairviewfittings.com)

LaRea

Thanks.  Amazon had next-day delivery on the 90 elbows, so I'll try them first and then look for 45s if needed.

LaRea

Epic fail.  The thread on the pump body is not 1/8" NPT.  It's 7/16-20 SAE with an o-ring.  

Plan B:  I bought a mini pipe bender ($20 overnight on Amazon).  I have four scrap hose fittings from the old transoms, so I'll practice on them.  If it works, and if I'm brave enough, I'll try bending the new ones from 45 to 90.  

Grahamu

Disregard I removed my comment

LaRea

Yes, if I can't make the pipe bender work.  I'd need second adapter to connect the 1/8" NPT elbow to the 7/16" SAE quick-release fitting.  

Dream_Inn

Sorry, but I'd still go with adapter and another 45 degree.  Bending something that is already prebent will not be correct and will probably weaken in certain areas.  This is because it may have been bent using heat.  Just my. 02.  

Take it from someone that has several pipe benders and use to bend RF hardlines for radars.  

LaRea

This is a tough parts search.  Every company has a different term for that thread.  I think all of the following terms mean the same thing:

7/16-20 SAE
7/16-20 UN/UNF
7/16-20 MS Straight Thread
1/8" O-ring boss
1/8" ORB

All I need is a 45 elbow male (one of the above) to female (one of the above), but I can't find one.  

@Dream_Innyou see why I'm hoping the pipe bender will work.  I have four practice attempts to convince myself it's safe.  It would have been so much easier if Merc didn't change the hose configuration.  

Grahamu

I agree with @Dream_Inn what you are attempting with the bending is very risky. You might want to consider a short tube to tube extension with a bend if necessary. A local hydraulic shop should be able to help.

LaRea

I guess time will tell if I should have listened to your advice!

I got the mini tube bender and tested it on the two scrap fittings.  It worked perfectly -- nice, smooth bends with no kinking or any sign of any distress to the metal.  The tool is small enough to make a bend very close to the fitting.  So I bent the new hoses, and I'm gonna call it success.  

Grahamu

good  to hear you were successful 

Grahamu

As a footnote mine are 45 degree bends but the pumps are installed much higher than yours allowing the hose to run behind the tie rod

LaRea

And the Merc installation manual shows hoses with a 45 degree bend.  Makes me wonder if Rinker modified my originals during assembly.  

Grahamu

I think so, I checked older hoses  and they are all 45 degree.

aero3113

Awesome @LaRea !! 

LaRea

And if anybody needs a mini pipe bender, you pay shipping and it's yours. 

aero3113

@LaRea , I’ll take it if you really don’t want it. 

Dream_Inn

I hadn't paid any attention to mine, but I bet they are 45 degrees after I had both transom assemblies changed.  Not sure what they were before though.  Oh well, it works.  Yours looks good!  Tool looks nice as well.

reneechris14

Nice work @LaRea keep that little tool you never know.

LaRea

Shee-it.  I've been collecting tools for 40+ years, and I have a lot of tools from my dad's collection.  To make room for the hydraulic crimper that I bought for this project, I sent a bunch of tools to Goodwill.  Every time I buy a tile saw, I say "I am never, ever, laying tile again, and this time I mean it." 

Aqua_Aura

I always justify my tool purchases with the money saved from DIY.