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Raceman
05-05-2018, 03:24 AM
This is on a Bravo 1. The trim will work up/down on trailer and sounds normal, but will not trim the drive up under power. When running along at speed if the throttle is pulled back, eliminating load on drive the unit will trim up and will hold in that position. There are no noticeable external leaks. The engine and drive were recently removed and reinstalled to install a new transom and this problem wasn't present prior to that time. I've never seen a pump that seemingly did not have enough power to trim up, but would hold in whatever position it's placed in. I've got a set of guages somewhere to check pump pressure, but can't lay my hands on 'em and don't know what the pressure spec is if I find them.

patchesII
05-05-2018, 05:24 AM
You sure the lines were put back in the proper position? I have seen that on our drag boats. Usually had to replace the pump

tux974
05-05-2018, 05:32 AM
X2^^ Sounds like they are reversed. Swap the UP & Down lines.

billybob
05-06-2018, 09:31 AM
yea swap lines. up pressure is about 3 times higher than down press. swap lines at pump.

Dave Strong
05-06-2018, 11:18 AM
This is on a Bravo 1. The trim will work up/down on trailer and sounds normal, but will not trim the drive up under power. When running along at speed if the throttle is pulled back, eliminating load on drive the unit will trim up and will hold in that position. There are no noticeable external leaks. The engine and drive were recently removed and reinstalled to install a new transom and this problem wasn't present prior to that time. I've never seen a pump that seemingly did not have enough power to trim up, but would hold in whatever position it's placed in. I've got a set of guages somewhere to check pump pressure, but can't lay my hands on 'em and don't know what the pressure spec is if I find them.

If you don't get this sorted and find your gauges I can get you the press specs.

Dave

Raceman
05-07-2018, 07:19 PM
Thanks guys. I think y'all fixed it. It appears the lines were reversed when the engine and outdrive were put back in the boat.

90 5.0
05-08-2018, 11:17 PM
I bought a boat that had the lines backwards for a long time (was that way when I got it and supposedly had never been apart ). Was always real slow but worked, though was just because single rams were slow, hit it with 24v and it blew up two days later.

Thats when i figured out they were backwards putting the new pump in.

tux974
05-09-2018, 05:09 AM
Easy to tell, it trims fine when you back off the load/throttles.

texasvector
05-09-2018, 07:22 AM
mine did same thing. .... had em backwards