Possable O/B Rig Issue?

[piperdriver]

This is a 1992 Javelin 389 Fish/Ski. 19' with an Evinrude 150XP on the back. Test drove teh boat and all was well except for one issue. Coming out of the hole just on plane the baot rides port(right) side low. This happens until you really trim the motor up. It seems as though you are on the trim button for a long time. While this is happening the steering wheel feels very "heavy". Then almost instantly the streering get's lighter and the RPMS pick up about 300-500. and the boat seems to level out. Any thoughts?

 

[seahorse5]

Re: Possable O/B Rig Issue?

...the baot rides port(right) side low.

First let's get the nomenclature correct.

Port is on the driver's left side while he is driving the boat. Starboard is on his right side.

 

[etracer68]

Re: Possable O/B Rig Issue?

Port = same amount of letters as left, also port= red wine. Sounds like you may have to ajust the trim blade on the motor, its under the cavitation plate in back. Make small ajustments to the side its hard to steer. You should be able to let the wheel go, while on plane.

 

[piperdriver]

Re: Possable O/B Rig Issue?

For goodness sake. How embarrasing is this. I am a pilot, and yes I kow port is left, but my fingers typed right. Any thoughts on the wheel feeling "heavy" until it is trimmed up? Is this an inhearant problem in these boats?

 

[etracer68]

Re: Possable O/B Rig Issue?

Does it steer hard both directions? The cavitation plate should be level to 1 inch above the bottom of the boat. Is the cavitation plate level with the bottom of the boat, when its all the way down? We need info from you to help.

 

[piperdriver]

Re: Possable O/B Rig Issue?

I will have the additional info hopefully tonight. Yes, it steers hard both directions until it is trimmed up. Thanks

 

[piperdriver]

Re: Possable O/B Rig Issue?

Ok, looking at the relationship between the cavitation plate and the bottom of the boat it looks like the cavitation plate is 2" or more ABOVE the bottom of the boat. We went out yesteerday and I ran a lot of different power settings/trim positions. With the load in the boat never changing it rode port-left side low. It would track straight, but left side low. The faster I would run and the higher I trimmed up the more level it would ride. At wide open throttle I was running 5500 RPM trimmed up. This is an Evinrude 150 Year model 1985. While wide open i kept trimming up until it began to porpose, then trimmed in just a tad to stop the porposing. At that point I was turning almost 6000 RPM. No gps to confirm speed. I did notice that the prop would cavitate often. That is the next fix. It was what I have found to be an older Evinrude 3 blade Stainless. 14.25X21. There is no cup at all on the blades, and it looks like the individual blades are reworked and very thin. I am going to go to a 4 blade. Could this left side low be a product of torque and old inefficiant prop?

 

[Silvertip]

Re: Possable O/B Rig Issue?

If the prop is ventilating (not cavitating) there is a good possibility the engine is also losing water pressure which is not a good thing. When trying to squeeze the last bit of performance out of a set-up it is a good idea to install a water pressure gauge. How weight is distributed in the boat will affect its attitude until speed gets high enough for it to begin behaving more like an airplane than a boat. (But even airplanes need trimming). You might want to check the engine mounting to ensure it is 90 degrees to the transom. If the engine is pivoted to one side or the other it can make the boat roll up on one side or the other.

 

[RRitt]

Re: Possable O/B Rig Issue?

is steering stiff without throttle? is transom solid?

 

[piperdriver]

Re: Possable O/B Rig Issue?

Silvertip--I have a water pressure gauge, and I have not noticed any drop in pressure in any of the configurations. RRitt--the steering is absolutely free and easy without any throttle. No binding at all. The transom is solid. No flex, no delamination, no soft spots. What is the best way to check the trueness of the motor in relationship to the transom?

 

[lncoop]

Re: Possable O/B Rig Issue?

Port = same amount of letters as left, also port= red wine. Sounds like you may have to ajust the trim blade on the motor, its under the cavitation plate in back. Make small ajustments to the side its hard to steer. You should be able to let the wheel go, while on plane.

Not to put too fine a point on it, but; Port = same number of letters as left, also Port = fortified red wine. Very yummy fortified red wine, but I digress.........

 

[piperdriver]

Re: Possable O/B Rig Issue?

Incoop--Thanks for beating that dead horse one more time. I guess the thread can end now, that was the technical expertise that I was looking for--

 

[Silvertip]

Re: Possable O/B Rig Issue?

You can eyeball the back of the boat with the engine down and sitting on a flat parking lot. Stand back about 25 feet and have a look. You can also center the steering and take some measurements from the center of the prop shaft to a sharp point on the bottom of the transom at either side. Dimension should be equalon both sides. That number obviously will vary unless you have the motor turned perfectly straight ahead.

 

[lncoop]

Re: Possable O/B Rig Issue?

Incoop--Thanks for beating that dead horse one more time. I guess the thread can end now, that was the technical expertise that I was looking for--

Actually, the dead horse I was beating belonged to etracer, and the beating was entirely good natured, as was his I'm sure. Nonetheless, it was not my intention to offend you, so please accept my apology. Hope you get your issue resolved.