regalman4925

i scrapped my idea to use omc trim hoses on my k planes so i have been searching the web for a affordable solution. i keep noticing that the inverted flare fittings that is used for mercruiser trim lines appear to be the same as brake lines from what i have figured out. anyone that has had hydraulic lines made knows it is not cheap to make them. whats stopping me from using the hard lines like the ones that the auto part store sells? i plan to mount my trim pumps on the transom about a foot above the k planes? those lines cost less then 5 bucks a piece from the parts store. 200-300 for hoses or 20 bucks for hard lines and i have 250ish to put in my gas tank and cover beer for a weekend of boating? i honestly think hard lines would look custom. from what i have seen online the brake lines are good for a minimum of 3000psi.

dereknkathy

the cylinders move as they extend-retract. must have a flexible hose between hull and cyl. you could run brake lines part way. parts stores have a box full of misc adaptors for brake lines. then hook to those merc trim lines for the last foot or so transom to cyls.

502ss

iTrader: (3)

Did you actually have custom flex stainless lines quoted from a hydraulic shop? I had all custom made lines for my trim cylinders and my steering cylinders plus long lines from the trim pumps(which are mounted at the front of the engine compartment) to the bulkhead connection under the gimbal. I think all those lines cost about $250. For what you need it shouldn't cost nearly that much, time to shop around!

I though most brake line for automotive is steel, your going to need to find stainless especially if they are outside the boat and below the waterline!

regalman4925

i am only thinking of using them on the inside only not the outside, they would see little or no movement. i can get new braided lines for the outside for 14 each so there is no issues there. as far as i have seen, the brake lines are rust resistant from what i am reading online. i have used these in the past on cars i still have as far as 10 years back and they are still not rusted so if its on the inside of the boat and fresh water i dont think that would be a issue. if i have my own lines made, the length doesnt appear to be where the cost is, the fittings seem to be the expensive part, about 25 each. honestly if i mount my trim pump a foot above my planes on the transom i cant really see a reason why hard lines would not be a good option. they are used on pretty much every single car, under them, in all conditions including salty midwest roads and hold up for decades. i have also used these same lines for fuel lines, technically our fuel lines in our boats are suppose to be hard lines after the fuel pump....

regalman4925

here is a pic tyo give you a idea of how short of a distance i have in mind. from the ports of teh trim tabs to the ports on the bulkheads mounted on the transom how the picture shows

fireboatpilot

I think the constant vibration and shock from pounding will lead the ridgid lines to fail early. If you insist on using auto parts which by the way will not be USCG approved, get the SS lines. Better yet how about the flexable brake lines?

c_deezy

iTrader: (1)

I used hard lines from my pumps to the k-planes. My pumps are right above my planes.

One side I used annealed stainless the other side I got tire of flaring the stainless and just used two short parts store lines. I don't see how there would be any flexing between the lines when they are mounted that close.

bustedbrick

You can put a few loops in hard lines to give a bit of "give". Done in automotive (mostly older) all the time around master cylinders and a good practice anytime you are not using a flexible section.

regalman4925

exactly what i am getting at. i think that looks nice too! thanks for the pics and info

as far as vibration you could make the same arguement for pretty much most mercruiser motors having a hard line from the fuel pump to the carb...

Twin O/B Sonic

I spent a bunch of time tryng to get mine done right and gave up and went to the local parts store.
My problem was all the hydraulic shops said they could make my lines based on all of them telling me they're 1/4" lines.
They're not. They're 3/16" and that stopped everybody dead in their tracks. I even got as far as a shop that makes them for Merc trying to supply me the 90* ends for my local guys to crimp. He also struck out.
20 hrs use and I'm more than happy. My old lines were fine but too long and I was trying really hard to keep the bilge uncluttered for additional storage. With the hard lines installed, they take up less room than the rubber hoses. I think I have $20. into all 4 lines for both tabs.