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View Full Version : Bravo Trim In Blocks?



snake plissken
09-03-2009, 03:07 PM
I believe thats what there called I just bought a new Bravo X drive and was wondering If I need to inslall the blocks that prevent the the drive from triming in to much My boat is a 1999 zx stepped hull if anyone can tell me about them that would be great thanks:nilly:

mrfixxall
09-03-2009, 03:25 PM
I believe thats what there called I just bought a new Bravo X drive and was wondering If I need to inslall the blocks that prevent the the drive from triming in to much My boat is a 1999 zx stepped hull if anyone can tell me about them that would be great thanks:nilly:

isnt it 1 nylon block? goes through where the trim pin goes...the hole is oval the it needs to go in their one way,stern or aft or their will be some slop in it..

MOP
09-03-2009, 08:03 PM
The blocks like Mike says must be installed, you need advice from another owner as all boats react differently.

snake plissken
09-04-2009, 12:33 AM
Im mainly asking stepped hull 22zx boat owners. There called Trim in Limit blocks I just found out

The Hedgehog
09-04-2009, 06:22 AM
I would install them. They keep you from trimming in too much and becoming more likely to spin out. If you have a handle on things you will be ok without them. If someone else were to drive your boat for some reason well....

Dr. David Fleming
09-11-2009, 01:41 PM
These things came on the 22zx installed on the shaft that goes through the trim cylinders - there are two blocks painted black that can be installed in a couple of ways to provide different trim limit.

This is now an obsolite setup as Mercury has replaced them with a different design and the old part is not available. The new part requires the trim cylinders to be disassembled and inserts installed inside the cylinders to prevent the trim cylinders from retracting all the way in. The new Merc part no. is Quicksilver 15768A 3

The biggest problem with the original design "aluminum blocks" is that they wore on the lower drive pivot and gradually wore to the point that they drop down and are not effective at limiting the drive anymore.

The 22zx with the step hull is a bit of a control problem boat and high speed with the drive all the way "in" causes "chine walking" and bow of the boat to dig and spin especially if you have the trim planes down.

If you look through the Donzi Registry threads this summer you will see where someone in Canada spun out a 1999 22zx clowning around with the trim. It through him out the windhield into the lake and the boat ran away.

My own 22zx has an option from the factory called "trim indicators" which give an accurate reading of the drive and K-plane trim tabs. I also have the external Latham hydraulic steering option on the boat. These make the boat much more stable over 70. I have removed the trim blocks on my 22zx as it trims much better for low speed running in waves. I have also accidentally trimmed the drive all the way "in" at speeds over 70mph. In careful hands the boat is controllable but it "chine walks" and is on the verge of handling problems.

By the way the "trim blocks" you are asking about can be welded and filed to restore their shape. I keep mine and install them again as "training wheels" when my family is going to be driving my boat - I also take off the lab finished propeller and install a stock prop for the same reason.

Dr. d