Trim Pump Troubleshooting-please help

UNSUREBOATGUY

Petty Officer 2nd Class
Joined
Sep 14, 2009
Messages
117
1987 Mercruiser 3.0 Alpha 1

The leg is dropping very slowly when the boat is parked. I walked by the boat the other day and noticed that the skeg was touching the garage floor. I know when I parked it, it was a little off the floor. I raised it a little yesterday and placed a piece of wood under it to see if it was really dropping. I found it resting on the wood today. There was a very small gap when I set up my "test"-just wanted to be sure I wasn't crazy.

Getting to the point...The pump is the oildyne version with the round resevoir. I looked for leaks, but didn't see anything obvious. The pump seems to work perfectly otherwise. The oil level is a little high, but the drive is not completely in (very close). The trailer is too low to get the drive all the way down even with it raised up on blocks and the tongue as low as it will go (a pain in the behind).

When I got the boat last fall, I found the vent closed-not backed out 1 turn the way it was supposed to be. I corrected this and all appeared to be fine. I just noticed the slow lowering this week, but the boat was stored over the winter with the leg almost all the way down. We've had it out a couple of times this spring.

I looked at the troubleshooting guide in manual #6, but I don't have the pressure testing equipment shown in the manual. Is there an easy way to know what is happening, or do I need to get the testing equip?

Thanks a bunch for any advice.
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,344
Re: Trim Pump Troubleshooting

Re: Trim Pump Troubleshooting

Are you sure it was a vent screw and not the manual release screw
 

UNSUREBOATGUY

Petty Officer 2nd Class
Joined
Sep 14, 2009
Messages
117
Re: Trim Pump Troubleshooting

Re: Trim Pump Troubleshooting

It was the one with the dip stick on it. I hope that was the right one:)

I guess I did not check the manual release screw-could it loosen on its own?
 

UNSUREBOATGUY

Petty Officer 2nd Class
Joined
Sep 14, 2009
Messages
117
Re: Trim Pump Troubleshooting-please help

I took a look-there does not seem to be any manual release screw-looks like some sort of factory plug in its place (just an empty hole with a plug in it). I could take a photo if it would help.
 
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