It's been awhile since posting here. I see it is still lively. I didn't know
Bush was such an avid boater.

I need help with a mercruiser trim system. This is a 12 page story that I will
shorten as best I can.

So I rebuild this 1976 Sea Ray. Totally put in new stringers, etc. etc. Have
the lower end rebuilt by my trusty local mechanic and initially, everything
works great.

I take the boat to Canada and hit a rock and my trim quits working. I get home
to find a loose wire, reconnect it and things work OK but I notice the lower
unit goes down at 1/2 the speed it goes up and sounds like it is straining.
Take it back to my mechanic and he tests and says it is a bad trim pump.

So I send the pump out to a guy I find on the internet in Florida that knows
what he is talking about and will rebuild it. He checks it out and says things
are fine - great pressure both ways. He puts on a small part and doesn't even
charge me. Ya gotta trust anybody that is THAT in to service. He says it is
probably the cylinders. Later that summer, one of the cylinders splits an
outside casing. So I buy complete rebuild kits and carefully rebuild them,
checking to see there are no bent rods, etc. However, it still goes down slow
and sounds like it is straining. At the end of last season, it was "sticking"
in the up position. The only way I could get it to go down was to bleed a
little fluid from the line. Once it started down, it worked fine but slow.

This year, I decide to replace the pump. I order what I think is a complete
pump (keep you eyes open on Ebay) and find it is the motor and pump housing,
but not the "guts" of the pump. Undaunted, I take my pump guts clean them
meticulously, carefully make a diagram so I am sure all the balls/springs get
back exactly, blow out the lines and reassemble.

At the time, I notice that the 4 ball/spring ports have an adjustment on them.
I can't find a schematic in my service book. Figuring the springs are almost 30
years old, my logic says tighten them just a smidge to compensate for age. I
turned each of them in a 1/4 turn.

Put the pump back together and, while trying to bleed the lines, the cylinders
will go UP fine but will not even go in the down direction before the pump
stops alltogether - even with me pushing on them full force.

At this point it has been 3 years, several trips to the mechanic(s) about $400
and my self image as a fairly decent home mechanic is shattered. I don't get
how there could be a malfunction in the pump guts, it is a couple of gears,
passageways, and spring/ball stops. The pump motor is new, the cylinders
rebuilt. I am afraid to pop another $400-500 for a complete pump to find out it
does the same thing. My current plan is to loosen the ball/spring adjustments
and try again. That failing, I go back to my trusty mechanic and make the big
pop for a new pump.

Any help/advice you can offer would be most appreciated. I would like to move
out of hell, and back into purgatory...

Dave Kirby
Proud Owner/Builder of the Wayward Sun
Richland, Michigan

Something else to check. There is an inline valve (for reverse
lock?), maybe it's plugged or otherwise out of whack. Mine doesn't
like to hold trim Stoopid mercruiser.




On 22 Jun 2004 01:09:48 GMT, (Ppleworks) pulled up
to the drive-thru window and hollered:

It's been awhile since posting here. I see it is still lively. I didn't know
Bush was such an avid boater.

I need help with a mercruiser trim system. This is a 12 page story that I will
shorten as best I can.

So I rebuild this 1976 Sea Ray. Totally put in new stringers, etc. etc. Have
the lower end rebuilt by my trusty local mechanic and initially, everything
works great.

I take the boat to Canada and hit a rock and my trim quits working. I get home
to find a loose wire, reconnect it and things work OK but I notice the lower
unit goes down at 1/2 the speed it goes up and sounds like it is straining.
Take it back to my mechanic and he tests and says it is a bad trim pump.

So I send the pump out to a guy I find on the internet in Florida that knows
what he is talking about and will rebuild it. He checks it out and says things
are fine - great pressure both ways. He puts on a small part and doesn't even
charge me. Ya gotta trust anybody that is THAT in to service. He says it is
probably the cylinders. Later that summer, one of the cylinders splits an
outside casing. So I buy complete rebuild kits and carefully rebuild them,
checking to see there are no bent rods, etc. However, it still goes down slow
and sounds like it is straining. At the end of last season, it was "sticking"
in the up position. The only way I could get it to go down was to bleed a
little fluid from the line. Once it started down, it worked fine but slow.

This year, I decide to replace the pump. I order what I think is a complete
pump (keep you eyes open on Ebay) and find it is the motor and pump housing,
but not the "guts" of the pump. Undaunted, I take my pump guts clean them
meticulously, carefully make a diagram so I am sure all the balls/springs get
back exactly, blow out the lines and reassemble.

At the time, I notice that the 4 ball/spring ports have an adjustment on them.
I can't find a schematic in my service book. Figuring the springs are almost 30
years old, my logic says tighten them just a smidge to compensate for age. I
turned each of them in a 1/4 turn.

Put the pump back together and, while trying to bleed the lines, the cylinders
will go UP fine but will not even go in the down direction before the pump
stops alltogether - even with me pushing on them full force.

At this point it has been 3 years, several trips to the mechanic(s) about $400
and my self image as a fairly decent home mechanic is shattered. I don't get
how there could be a malfunction in the pump guts, it is a couple of gears,
passageways, and spring/ball stops. The pump motor is new, the cylinders
rebuilt. I am afraid to pop another $400-500 for a complete pump to find out it
does the same thing. My current plan is to loosen the ball/spring adjustments
and try again. That failing, I go back to my trusty mechanic and make the big
pop for a new pump.

Any help/advice you can offer would be most appreciated. I would like to move
out of hell, and back into purgatory...

Dave Kirby
Proud Owner/Builder of the Wayward Sun
Richland, Michigan

Something else to check. There is an inline valve (for reverse
lock?), maybe it's plugged or otherwise out of whack. Mine doesn't
like to hold trim Stoopid

Could be that a piece of rubber from inside of the hose stopped up one of the
hoses from the inside.