Trim pump wont go down????

[riskibusiness]

OK I rebuilt my shifter and reinstalled it today. Everything works great except the trim down. The pump runs when I push the button but it doesn't go down. It does go up. Any body got any ideas. 1980 wellcraft 170, 470 mercruiser with the old style quicksilver control

 

[Bondo]

Re: Trim pump wont go down????

OK I rebuilt my shifter and reinstalled it today. Everything works great except the trim down. The pump runs when I push the button but it doesn't go down. It does go up. Any body got any ideas. 1980 wellcraft 170, 470 mercruiser with the old style quicksilver control

Ayuh,... Jump on the outdrive, with the pump runnin' Down....

 

[O-fishal]

Re: Trim pump wont go down????

Find the trim relays and swap them with each other if it goes down and not up one of the relays is shot!

 

[riskibusiness]

Re: Trim pump wont go down????

Ayuh,... Jump on the outdrive, with the pump runnin' Down....

Are you serious? because I thought about doing that!!

 

[Don S]

Re: Trim pump wont go down????

Find the trim relays and swap them with each other if it goes down and not up one of the relays is shot!

It doesn't have relays, it has solenoids, and they are working or the pump wouldn't be running.

Originally Posted by Bond-o
Ayuh,... Jump on the outdrive, with the pump runnin' Down....

I agree, what happens, is when you raise the drive, and bog the pump motor down, the valves have a tenency to hang open due to the pressure. Get in the habit of putting the drive up, when you hear the pump bog down, just trim down for a second just to relieve the pressure on the valves.

 

[greg82255]

Re: Trim pump wont go down????

Are you serious? because I thought about doing that!!

On my old Merc 898 I definitely had to jump on the drive once or twice to get it to trim down.

 

[riskibusiness]

Re: Trim pump wont go down????

It doesn't have relays, it has solenoids, and they are working or the pump wouldn't be running.




I agree, what happens, is when you raise the drive, and bog the pump motor down, the valves have a tenency to hang open due to the pressure. Get in the habit of putting the drive up, when you hear the pump bog down, just trim down for a second just to relieve the pressure on the valves.

yeah it did bog a little when I got it to what i call trailer position. But this is the first time its ever not gone down. So what your saying is in the future when it bogs just bump it down real quick?

 

[Don S]

Re: Trim pump wont go down????

yeah it did bog a little when I got it to what i call trailer position. But this is the first time its ever not gone down. So what your saying is in the future when it bogs just bump it down real quick?

Yes, just enough to relieve the pressure.

 

[Pete104]

Re: Trim pump wont go down????

That does work?! But if you add another ounce or so to the resevoir, you should have enough for "down" pressure. Make sure the vent is open the recom 2 turns.

 

[riskibusiness]

Re: Trim pump wont go down????

O.K. it went down while my son stood on it. And it still goes up fine but wont go down on its own. The reservoir was a little low so i topped it off. I took the rams off the out-drive and they don't go down then either???

 

[Don S]

Re: Trim pump wont go down????

Then you need to do some pressure checks on the trim system to see if the pump is putting out any pressure in the down position, or the trim rams are binding.
When going up, is it real slow? Should only take about 10 seconds to go from full down to full up.

 

[riskibusiness]

Re: Trim pump wont go down????

Then you need to do some pressure checks on the trim system to see if the pump is putting out any pressure in the down position, or the trim rams are binding.
When going up, is it real slow? Should only take about 10 seconds to go from full down to full up.

goes up just like its supposed to. bout 8 seconds or so

 

[achris]

Re: Trim pump wont go down????

Sounds like the end caps might be corroded. When your son is standing on it and it is going down, does it make a squealing noise? Also check the piston rods for scrape marks. Either one of those signs means the end caps have corroded and are grabbing the rod. The reason it will go UP is because the UP pressure is around 3,000psi, operating on the full area of the piston. The DOWN pressure is about 1,700psi and only operating on about half the area of the piston (due to the rod being in the middle)...

Chris.....

 

[Don S]

Re: Trim pump wont go down????

Does the trim pump motor sound like it's bogging down under pressure when you try to trim down, or does it sound like it's not pumping anything.
I still say you need to do some pressure checks, if you have a valve stuck or leaking or ???? in the pump, it won't build any pressure.

 

[Don S]

Re: Trim pump wont go down????

Sounds like the end caps might be corroded. .

I was thinking that too, but since it goes up in 8 seconds, it doesn't sound like that is the problem. They are usually slow going up as well, when they won't go down from corrosion.

 

[riskibusiness]

Re: Trim pump wont go down????

to me it sounds like it isnt pumping anything when going down. It only boggs when it gets to the limit going up

 

[riskibusiness]

Re: Trim pump wont go down????

so I guess tomorrow I will pull the down hoses at the outdrive and see if I get fluid out of the line when I push the down button

 

[Don S]

Re: Trim pump wont go down????

It needs to pump pressure too, not just volume. You could get plenty of fluid out, but if it's only got 1 psi of pressure, it will not push the drive down.

 

[riskibusiness]

Re: Trim pump wont go down????

O.K. boys which one is the down hose. I have a clymer manual but the pic it shows is totally differentView attachment 128053 from my unit

 

[Don S]

Re: Trim pump wont go down????

Can't you find some smaller pictures ???????? Upload the picture, not the thumbnail.

I have a clymer manual but the pic it shows is totally different

See what happens when you try to use a knee pad for a service manual. Here, download the OEM manual for your drive
http://www.4shared.com/document/wPl4tS8_/Service_Manual_04.html

Then turn to section 5, page 5-7 for pictures, and how to pressure test it.