I made this six second video yesterday to show one of the main reasons your high performance bass boat has a tendency to "Chine Walk" at high speeds & high trim angles. If you have ever experienced chine walk at 70+ mph it can be a scary thing. There are few things more exhilarating than flying down the lake at 75 mph passing your buddies and looking back at your roostertail. I freely admit it. It is an adrenaline rush.
Yeah, I know there is the "
You can't catch a fish at 70 mph" crowd out there and this post will be total nonsense to them.
This is a brand new *Merc 250 ProXS with Zero hours. If you were wondering why your boat does some crazy things at times try this. With the boat on the trailer and your transom saver removed grab the back of the lower unit and shake it back-and-forth. This does not get better with age. The mounts get softer and the side to side play gets worse.
The soft rubber motor mounts that comes from the factory in the ProXS motors are designed to minimize the vibration you feel in the hull and steering wheel while the motor is running. While this can make your boating experience more pleasant, it also exacerbates the chine walk on a high-performance hull.
The more the motor is allowed to move around the more side to side play you will have at high speed. The faster you go the more critical it is to minimize this movement. The boat in the video had the new style Seastar hydraulic steering system that so many boats have today.
And before you ask,
No, the steering wheel never moved while I was flopping the motor back & forth. That is 100% motor mount related. Some of you may say, "Mercury needs to fix that". They already have: It is called Merc Racing Motors. Merc Racing motors come from the factory with more rigid mounts up top and solid mounts in the lower to address this very thing.
Steering systems can also be culprits of ill boat handling. Air can get air trapped inside. This will cause slop in the steering as well. Most boats five years of age or older will need fluid added and the system bled by a competent mechanic to ensure safe operation. The way you can trouble shoot this is to move the steering wheel side to side One Inch. If the motor moves you are most likely good.
If you move the wheel and the motor does not respond, you have air in the system and this will exacerbate the problem. There are two sets of motor mounts on all outboards. There is an upper set that you have to remove the powerhead to swap out which is a major pain. Then there is a lower set that can be done in 45 minutes by most good do it yourself guys. Unfortunately there is not an aftermarket set of motor mounts for the new V8 Mercs as of yet.
There are a couple of aftermarket companies that make solid metal motor mounts that will virtually eliminate this movement thereby making your boat handle much better than ever before. Bob's Machine Shop in Fla makes some of the best. I am not endorsing any products here. Not on anyone's pro-staff.
While I do not consider myself an expert on all things boat related, I have owned 28 boats over the years with five bass rigs that would run 100+ mph so I have
lots of experience. I have taught probably three dozen guys how to drive their boats that they swore were Undrivable at top speed. I hope this helps some of you and possibly even saves someone's life. If you have ever been thrown from a boat at 70 mph it is No Fun. Been there & Done that. I know there are few of you that will care to change out your motor mounts but at the very least please check your steering system.
The water is cooling down on all North TX lakes right now and the chances of dying of hypothermia is very high if you spend more than a few mins in 50 degree water. Y'all be safe.
*My Yamaha 250 SHO is worse than this because it is now 7 years old.