Outdive won't trim up at WOT.
 

Since I got my motor back together I can't get it to trim up above 4500rpm when I have 4-6 onboard. I am pushing about 600hp though a B-1 with a 24P.

I normaly am able to have it trimmed where I want it before I go WOT. But this W/E i got beat by a boat I know I can outrun during a short sprint from about 30mph. And you guys know that can't happen again :D

Is this just a weak trim motor or do I need an upgrade. The outdrive was a 91 model with a 330 454 motor. Trim motor has the plastic reservoir underneath.

If I hold the trim up button it will trip the thermal overload so I know the motors trying.

Re: Outdive won't trim up at WOT.
 

Anyone?

Re: Outdive won't trim up at WOT.
 

Any chance you've got the low and hi pressure hoses reversed?

Re: Outdive won't trim up at WOT.
 

Not sure about that Gary. They have been off, but the drive goes up when I push up. If they were reversed, wouldn't it be backwards?

Re: Outdive won't trim up at WOT.
 

If it's wired backward AND plumbed backward, then it will go up but not hold on the low pressure side.
You should also consider it may be leaking past the trim cylinder seals.

Re: Outdive won't trim up at WOT.
 

Gary,

I'll look into the high low thing, anythings possible. It doesn't leak down at all, so I'm assuming cylinders and check valves OK.

Are all the B-1 trim pumps the same?

As I look at pump which should be The high pressure out port?

Thanks,

Re: Outdive won't trim up at WOT.
 

Not sure which pump you've got, there are several types. It's easier to check wiring.
Blue should be energized for trim up. Green for trim down. If that's OK, your plumbing will be OK.
On certain pumps, you can replace the regulator on the bottom. But if it'swired/plumbed OK and still doesn't work, I would suggest just buying a new one. BAM may have a good deal on pumps.
Gary

Re: Outdive won't trim up at WOT.
 

Gary,

looks like this one, as mentioned, it operates perfectly on the trailer or up to about 4500rpm in the water. I will check the wiring. Hope it's not the motor, about $900.00. Could it be anything mechanical in the outdrive/gimbal?

Re: Outdive won't trim up at WOT.
 

I doubt it is the motor, I have never seen one go. But you may need to get a brush kit and replace the brushes, it is much more common.

Re: Outdive won't trim up at WOT.
 

Where can I find a brush kit. Nobody seems to list internal parts for the trim motors?

Thanks,

Re: Outdive won't trim up at WOT.
 

Merc part number 17631A1, list price $42.10. Any Merc dealer should have them.

Re: Outdive won't trim up at WOT.
 

Thanks Mr V, I'll order a set and see if that helps.

Re: Outdive won't trim up at WOT.
 

Check BAM for a discount.
http://www.go-fast.com/trim_pumps.htm

Re: Outdive won't trim up at WOT.
 

I was looking on their other website. $490.00 is a great price.

Thanks,

Re: Outdive won't trim up at WOT.
 

Check the simple things first if not already like where the trim limiter is set. Maybe limiter is shorting out when drive is under load vice hanging in the driveway. Does it trim up if the trailer button is used while running at 4500rpm? Fluid level? I'm only suggesting becuase I haven't read what you've done to try and isolate it. My experience with boats has always been to methodically go thru the simple crap prior to thinking on a more complicated level. Good luck.

Re: Outdive won't trim up at WOT.
 

An easy way to remember the wiring on the pumps is this; Blue=Sky (up), Green=Ground (down).....

I've seen the cylinders go bad more than the pump itself but, you've got to check both.

Re: Outdive won't trim up at WOT.
 

Thanks guys,

Didn't think to try the trailer trim button, The trim limiter could easily be part of it. Fluid is ok, i assume rams ok because no fluid leak and does not bleed down once up.

I will be checking all the possibilities listed here tonight and then trying a brush set.

Re: Outdive won't trim up at WOT.
 

Are you sure the trim pump is running when you try to trim up at 4500rpm? Check that first of all. I had a similar problem last year.

What caused it was that the trim cables in the throttle control got short cutted above a certain angle of the throttle control...

Re: Outdive won't trim up at WOT.
 

Thomas, It sounds to me like the pump hoses are reversed. If you need a pump go aftermarket discount marine site. I got mine for 300 a piece two years ago. On your pump hoses you can switch them on the bottom of the gimbal housing at the hose manifold. I had the same problem a couple years ago when i put mine back together. It would trim till I hit the throttle, then theprops would push the drives back towords the transom.