Equalizing two outdrive trim pumps?
#1
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One of my Bravo XR drives moves in or out at about twice the rate of the other. Everything is new and fluids are clear and properly filled.
Is it possible to equalize these? At this rate the trim switch in the throttle is useless as it operates both pumps.
I assume this has been hashed out before but I haven't found the thread.
Is it possible to equalize these? At this rate the trim switch in the throttle is useless as it operates both pumps.
I assume this has been hashed out before but I haven't found the thread.
#2
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Are you sure that both pumps are "identical"? Bravo pumps have a different flow rate than tab and other drive pumps.
If they are both the same, look at the size and length of the main power cables to the batteries. Voltage differences change the rate substantially, especially when trying to trim out against a thrust load from the prop. Drives trim out against a load slower than at the dock. Likewise, they trim in faster with the prop thrust.
If they are both the same, look at the size and length of the main power cables to the batteries. Voltage differences change the rate substantially, especially when trying to trim out against a thrust load from the prop. Drives trim out against a load slower than at the dock. Likewise, they trim in faster with the prop thrust.
#3
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Actually they are on the trailer as I watch them. I will double check all the wiring but I recall they are nearly identical in everyway. They were rigged very nicely by the factory.
#4
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Do they run to the battery for each individual engine (different supply voltage)? Are you checking them with the engine(s) running (good supply voltage, batteries charged). It is inevitable that there will be differences between 2 pumps. Even slight electric motor hp/rpm differences show up quick. Also, if there are any internal frictional differences in the cylinders or a restriction in a line (check the "screens" in the brass pump fittings) it would slow that side down. Good Hunting!
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I re-wired my boat to insure that both pumps
are powered from the same point (they used to
be wired to their respective engine).
I remember after camping on the boat where we
nearly run down one engine, but the other is ok,
that the low ones trim pump was much slower
until the battery charged. They are very voltage sensitive.
They will never be perfect but wired together will
make them as close as they get. If they are radically
different after that you may need a pump or cylinder
overhaul on the slow one.
Pesky Varmint
are powered from the same point (they used to
be wired to their respective engine).
I remember after camping on the boat where we
nearly run down one engine, but the other is ok,
that the low ones trim pump was much slower
until the battery charged. They are very voltage sensitive.
They will never be perfect but wired together will
make them as close as they get. If they are radically
different after that you may need a pump or cylinder
overhaul on the slow one.
Pesky Varmint