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NEED HELP CAN'T DRIVE

wickedrister

Active member
Ok I tested the new set up today. Wow! It runs 61 by the speedo with the nose pushed all the way down. Running with the nose down feels like I am runnig in mud. Water pressure is not good 5 psi running slow 10 psi at speed but good flow of water out the P-hole at all speeds and no bolw out. I never looked at the tac don't ask me why I just messed up and didn't look. Had my hands full. RPM's never sounded high. The JP is adjusted all the way down, the motor is mounted on the center holes. The center of the prop shaft is 4" below the pad. My plan is to lower the motor one hole and retest. If I try to trim the nose up "any" at speeds over 50 or 55 mph way bad things start to happen. The first stages of my chime walk are really nasty. I get a strong revolving or dipping sensation. No way I'm going to try drive past that mess. When it starts it's hard as heck to calm down. I have to ease the nose down and ease off the power at the same time to get it back in check. If I just get out of the power it dives to one side like crazy. It looks like I need to work on my set up , learn to drive or get really brave? I really think when my problems are worked out it will run a solid 65 to 68 mph and not be a hand full. I'm lookig for any suggestions. I don't want to take the family out the way it's acting,THANKS! (ps, i'm told a 4 blade may be a big help)
 
Chine walk

Hey Wicked, Sounds like you are experiencing the thrill of going fast! If you drop the motor down and bury the prop, more than likely, it will get worse. Two things that I think will help is 1, raise the motor up, not down. 2, go to a larger diameter prop or try a 4 blade prop. If you are interested, I have a 14 3/4x 23 SpeedZone on hand if you would like to try it. I think you have my phone number, if not, 304-619-5185. boatman
 
BOATMAN

What about the low water pressure? Don't I want to see around 15 to 20 pounds at WOT? I reckecked the water lines to make sure I had no kinks or problems and it looked fine. If I go up on the motor won't I add to the low pressure problem? I am running a stock water pick up. Do I need to get the Merc scoop kit? Two questions about the prop. Is the 4 blade an SS prop and will you take my new laser in on trade? Thanks!
 
Water pressure

Wicked, My 2.5L 200 merc had about the same water pressure. It scared me to start with, but found out later it was ok. never had a problem with it. The solid motor mounts for the bottom are a fairly simple swap. To install the top one's, you have to pull the power head. As for the prop, the one I have is a 3 blade. The increase in diameter will help keep the bite and along with the heavy cup, will help with lift and may keep you from having to trim so much. If you want to try the prop, you pay the shipping and run it. If you like it, we will work some kind of a deal. You need to see if it will help first. Thanks, boatman
 
Put in the solid lower mounts. You can get them Bob's machine shop for $50. Then about an hours worth of labor to install. Put on water pick-up scoop kit from Merc.. Then jack up that motor so the propshaft is about 2"-2.5" below the pad. You need to check your water pressure guage and also make shure you are reading the press at the right place on the motor. You need a minimum of 7-8 psi. at 5000 rpm's to collapse the water steam pockets. This reading is taken at the top water jacket plug. This is located just behind the flywheel. Prop testing with the motor that low is futile. Get your set-up closer then start testing props..
 
Motor mounts

The solid motor mounts from Bob's Machine Shop come in a set of 4 ( 2 upper and 2 lower). They retail for $75. My cost is $60. If you need them, you can have them for my cost+ shipping. boatman
 
GOFAST

addgasgofast said:
Put in the solid lower mounts. You can get them Bob's machine shop for $50. Then about an hours worth of labor to install. Put on water pick-up scoop kit from Merc.. Then jack up that motor so the propshaft is about 2"-2.5" below the pad. You need to check your water pressure guage and also make shure you are reading the press at the right place on the motor. You need a minimum of 7-8 psi. at 5000 rpm's to collapse the water steam pockets. This reading is taken at the top water jacket plug. This is located just behind the flywheel. Prop testing with the motor that low is futile. Get your set-up closer then start testing props..
Thanks for the suggestions. Ok my water pressure is pulling fron the top as you said so I think it's correct. I will order the scoop kit today part#17280A 2. I have got to get this thing to drive better before I can take the family out. I know that no one runs them but I almost feel like testing with the whale tail once. The 135 had a stingray on it when I got it so I have one to try. I installed one on the boat when it was under powered and I really liked what it did for the boat. At that time the boat ran only 43 mph. Now that it's running over 60 the whale tail may be a bad idea. I'm told they can do crazy things at high speed.
 
Definitely put on the water scoops. You really don't want lower water than 10psi @wot.
Then you need to raise the motor, a quarter inch at a time. That should make a big difference, you will be surprized. I'm guessing, 3" under the pad.
I disagree that you need solid mounts. At 60+ mph they are not your problem. I don't have them on either of my Mates. If you do them you have to do top and bottom, and there is no way it is one hour labor.
Finally, I would not start prop swapping until I had everthing else dialed in. Personally, I think you have the right prop for your setup, you just need some tweaking and some seat time.
 
Oh, one other thing, it is going to settle way down with a passenger in the other seat. At 60 MPH my Diplomat can get rocking wildly in the chop, with a passenger, I couldn't do it if I tried.
 
One thing to keep in mind, is it's great to be focused on water pressure, as many other people seem to be. But the real worry is overheating. So to me the best way of determining if you have enough water pressure is with a temperature guage. ;)
 
Actually Chris, water pressure and a temperature gauge is the best way to go. A drop in water pressure will have a direct impact on engine temperature as cooling water flow has been reduced causing an increase in temperature and potentially spoiling your day. So both gauges are a great investment.

As far as the motor mounts go, taking the power head off is not rocket science, if you are at all handy, like most of the guys on the forum you can do it. if you aren't sure get the manual from a merc dealer. if you talk real nice to them and they have high speed internet, you can download the service manual onto a disk and read it in pdf format.
 
If you install the mounts do it all at once. Its not good run just the lower. Buts stress in places that really don't like it. Get the scoops, and jack that baby up. Mine had the same problem with the motor buried. Jacked it up and switched props and OH YEA, different boat.
 
Wicked...

First off.. The guys have all GOOD advice...

The solid mounts aren't really necessary, but you may want to replace the lower to with fresh factory ones if the seem sloppy (it's an EASY job)! FYI: Solid mounts should always be done top & bottom... doing only the bottom can cause housing cracks as upper still wants to move and all the load is placed on twisting the lowers.

The higher you put the motor, the less chine-walk! You will find a sweet spot, but you MUST have water pressure... so too high is no good either!

Do NOT run a whale tail or cav-plate fin...dangerous above 50mph!

>>>Water pressure IS AN ISSUE with your motor! For $60 in parts and an hour of labor, its cheap insurance and an easy job to change a water pump impeller and thermostat's (one in the top of each head). From the sounds of things, you either have no thermos in it, a shot impeller, or a sticking popit valve (controls water pressure). Being the motor is new to you, I would change the common things, but you SHOULD have better water pressure than that (is the gauge good)???

Your 23p Laser II should be on the money when you get everything dialed in (depending on your gear ratio). A 4-blade will give you better control and cruising efficency, but get your other issues set first before the great prop chase begins.

Have fun but be safe! :devil: Jim.
 
LEARNING TO DRIVE

Thanks for all the comments and information. I now see that I don't need to go and make a bunch of changes all at the same time. The solid mounts are out for now. I'm going to get the scoop kit to help the water pressure and bump the motor up some then retest. This time I will keep an eye on the tac. I also know that only seat time will fix the nut behind the wheel that keeps working loose :thumb: THANKS YALL and Thanks Gary
 
What were the water conditions like when you tested?
To my suprise My predictor was impossible to open up in anything less than perfect conditions. After getting used to it a bit I could give it a little more juice but still even the slightest chop the boat would dance like crazy.
If you have a passenger with you it will help alot.
If the water is like glass there should be just about no chine walk.
welcome to the 60+mph club wicked:banana:
PS we wanna see some pics of this baby in action
 
Boston

Thanks man, I had a good steady 4 to 5" chop on the water. Had 2 in the boat. If Dad got all the way up in the front of the boat it did feel some better. THANKS
 
Water Pressure No One Quick fix

OK let's say I had a new water pump impeller, my thermostats were good and I had a new gauge and install kit that was pulling from the top of the head. Then the problem is water pick up related or pop-it valve related. I don't know where the pop-it valve is located or how to check it so if yall have any information on that it will be a big help. Now moving on, when I take a straight edge and hold it on the pad letting it extend rearward past the motor with the motor at zero trim the line is below a few of the water inlet holes. If the boat is running WOT will that line represent the true water hight on the lower unit. If so then I can see why I have a low water pressure problem. It shows that the motor will be sucking air in the top two or three holes. Is this correct or does the boat really ride down deeper in the water at WOT or at midrange power? Is plugging the top hole or holes a good way to correct the problem rather than running the scoops. It seems like the scoops could be blocked off with trash really easy and if you were not keeping a close eye on the gauges you could have a big problem. I don't see how one can run the motor so high like 1 1/2" to 3" below the pad with no nose cone style low water pick up system and keep good water pressure. I'm at 4 1/4" below the pad now and only picking up with 75% of the inlets if my water line off the pad is correct. One S&F member told me to go on up with the motor. Plug the top two holes and open up the size of the bottom two holes:confused:
 
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