JarJarBlinks
Cadet
- Joined
- Apr 20, 2009
- Messages
- 22
Background: 1973 Mercury 115HP Outboard 2 stroke. Extremely well taken care of through the years, needed 1 rebuild due to general wear and tear.
Problem 1:
OK when I bought this engine/boat, the PO stated that the trim unit leaks a little bit and it just needs topping off every other year. I was curious why it was leaking and I traced the problem to a threaded hydraulic line fitting going into the trim pump. It could be either the threads on the fitting or the sealing surface of the "nut" to the line. Really hard to tell which...
Anyone have an idea on how to figure out that problem?
Problem 2:
Apparently it has been over 2 years since the trim unit has been filled as some air got into the hydraulic lines. The pump will make a high pitched "air in the liquid pump" sound when trimming down but not up. The nose goes away when the engine hits the lower stop and the trim lines "tighten up". The engine still raises/lowers just fine and it isn't any noticably slower than before.
I figure that having air in the lines isn't a good thing so I have been trying to bleed the air out of the system. The engine has 2 cylinders so I bleed them according to my service manual. On 3 of the 4 bleed screws, when first loostened the fluid came out quite vigirously and during the actual bleed process the fluid spouted out by an inch or 2.
But for the Down bleed screw for one cylinder there was problems. When I removed the bleed screw there was very little residual pressure in the line and therefor little fluid came out. During the bleeding process itself, fluid came out MUCH slower than the rest of the ports. 1 air bubble did come out, but it did not make a difference with the noise.
Why does the fluid come out so much slower from this port?
In sumation:
1) What is the best way to fix a leaking hydraulic line fitting?
2) Why does oil come out of 1 bleed screw much slower than the other 3 and resulting in not fixing the air problem?
Any ideas?
Thanks!
Problem 1:
OK when I bought this engine/boat, the PO stated that the trim unit leaks a little bit and it just needs topping off every other year. I was curious why it was leaking and I traced the problem to a threaded hydraulic line fitting going into the trim pump. It could be either the threads on the fitting or the sealing surface of the "nut" to the line. Really hard to tell which...
Anyone have an idea on how to figure out that problem?
Problem 2:
Apparently it has been over 2 years since the trim unit has been filled as some air got into the hydraulic lines. The pump will make a high pitched "air in the liquid pump" sound when trimming down but not up. The nose goes away when the engine hits the lower stop and the trim lines "tighten up". The engine still raises/lowers just fine and it isn't any noticably slower than before.
I figure that having air in the lines isn't a good thing so I have been trying to bleed the air out of the system. The engine has 2 cylinders so I bleed them according to my service manual. On 3 of the 4 bleed screws, when first loostened the fluid came out quite vigirously and during the actual bleed process the fluid spouted out by an inch or 2.
But for the Down bleed screw for one cylinder there was problems. When I removed the bleed screw there was very little residual pressure in the line and therefor little fluid came out. During the bleeding process itself, fluid came out MUCH slower than the rest of the ports. 1 air bubble did come out, but it did not make a difference with the noise.
Why does the fluid come out so much slower from this port?
In sumation:
1) What is the best way to fix a leaking hydraulic line fitting?
2) Why does oil come out of 1 bleed screw much slower than the other 3 and resulting in not fixing the air problem?
Any ideas?
Thanks!