99 VP SX Trim Issue, continuosly runs in "down" postion

mikeneal

Senior Chief Petty Officer
Joined
Jan 28, 2004
Messages
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I noticed this morning that the drive was trimmed all the way down into the ground (typically I trim almost all the way down, stop right @ skeg to flush). And there was trim fluid running out of the bilge. Long story short, the trim automatically trimmed itself down, ran until battery was dead and got the motor/pump way hot, hot enough to melt the plastic reservoir. (hence the fluid leak). Removed the pump assembly and have a new reservoir but in checking the wiring / relays the "down" wire is energized all the time. So either the trim switch in the control box failed or the wiring has a short. (betting on the trim switch because the boat was uncovered in lots of Fay rain recently and the trim button has small hole where your thumb activates it, plus short to +12V, seems odd.) My problem now is...how do I remove the control box assembly? I removed the 3 self tapping screws, but acts like it will not come thru the side of the boat. (see pic). I posted a pic on the boat topics not engine, but since then I found out I believe it think it is VP part, so I posted a longer story here, hopefully they can delete other post if I am violating site policy.
 

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Don S

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Re: 99 VP SX Trim Issue, continuosly runs in "down" postion

Before you take the control all apart, back at the pump there is a plug with 3 wires in it. that goes to the control. Disconnect it and check the control sing an ohm meter. You shouldn't have any continuity between the red and green wires. If you do, that would indicate the switch is bad.
I have also seen the trim relays on the pump fail and do the same thing.
 

mikeneal

Senior Chief Petty Officer
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Jan 28, 2004
Messages
710
Re: 99 VP SX Trim Issue, continuosly runs in "down" postion

I have the pump off and I do not recall seeing a plug w/ 3 wires. I have an "up" and "down" relay and a 10amp fuse. With the relays removed I have a steady 12+ on what I believe is the sense wire for the down relay. I say "believe" because I have a factory service manual for the boat and my wire colors do not totally match up what is listed in the manual. I am using the schematic though and I am pretty sure the "down" wire that gets energized when you depress the "down" button has solid 12V all the time.
Before you take the control all apart, back at the pump there is a plug with 3 wires in it. that goes to the control. Disconnect it and check the control sing an ohm meter. You shouldn't have any continuity between the red and green wires. If you do, that would indicate the switch is bad.
I have also seen the trim relays on the pump fail and do the same thing.
 

Don S

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Re: 99 VP SX Trim Issue, continuosly runs in "down" postion

What is your full engine model number?
 

mikeneal

Senior Chief Petty Officer
Joined
Jan 28, 2004
Messages
710
Re: 99 VP SX Trim Issue, continuosly runs in "down" postion

5.0QL PWTR serial # 4110175131
 

Don S

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Messages
62,321
Re: 99 VP SX Trim Issue, continuosly runs in "down" postion

Thanks, it's a WT model, that's what I was looking for.
Still, you need to locate the plug, disconnect it and check the control switch wiring from the trim pump forward. Before you take it all apart.

SXtrimwiring.png
 
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