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Was a nice day so we took the boat out for the first time

jobe05

Member
Im attaching a short video of the water splash that I get from around the leg of the motor at water level. The splash is so high, as you can see on the video, it hits the side cover of the engine. What would cause this??

https://youtu.be/w_fEsPtRidM


I noticed when I got home, the position pin (if thats what it is called) that holds the position of the motor was up a little, so I lowered it one notch and that seemed to make the leg a little more parallel to the transom. Would that solve this? Sorry the pics are sideways, I tried everything..... But you get the jist...

IMG_3217 (Small).JPG

IMG_3218 (Small).JPG
 
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I could be wrong without a better photo showing the motor and bottom of the boat alignment. But to me it looks like the motor is tilted down too much, not up too much. You don't necessarily want the motor parallel to the transom but you do want the cav plate of the motor parallel with the bottom and a bit lower.
 
I think your right. I left it in the position the previous owner had it in thinking that is where it should be, but based on everything else I have fixed/replaced on this Boat/Motor/Trailer, I should have known better. Next time I have it out, I'll tinker with the adjustment and see what is best.
 
As said before, can't tell unless we see a side shot of your set up taken at hull bottom level, but my impression watching the clip is that you may have too much motor in the water.
I had that same issue on a dinghy once after replacing the motor which was a bit heavier than the previous one and maybe an inch longer (although in the same short shaft category), resulting in the motor being dipped in water more than it should have been, and I had the "spraying" issue as well. I fixed it by adding a 1/2 inch riser on the transom top and finding the right hole for the trim angle.
As far as the angle is concerned, just do some runs trying several different holes and find the one that works best, that's something easy to do while out on the water.
Good luck! And nice looking "oldie but goodie" Evinrude btw ;)
 
I just got a close look at your pics and the problem is not the engine height. The issue is your depth finder transducer is installed upside down. I've circled it in red. Your video shows all the water spray on the starboard side of the engine which is exactly where you have the transducer. Remove and reinstall the transducer as shown below and your splashing problems will go away.
transom.JPG

The 'V' side of the transducer should be facing down with the point of the V facing toward the bow. Below is a graphic from Sternmate showing correct transducer orientation.
transducer_correct.JPG

They have a really nice how-to web page showing the correct installation and orientation for a transducer.
http://www.sternmate.com/Where.html
 
The picture was taken when I was adjusting the side rails on the trailer, but in order to put them back on correctly, was to move the boat over about 4 inches. The transducer would have hit the one of the bed board so I moved it out of the way in order to move it without breaking it off. Good eye though, and thanks for reminding me I have to put it back in place before I go out again.
 
I just got a close look at your pics and the problem is not the engine height. The issue is your depth finder transducer is installed upside down. I've circled it in red. Your video shows all the water spray on the starboard side of the engine which is exactly where you have the transducer. Remove and reinstall the transducer as shown below and your splashing problems will go away.
View attachment 19162

The 'V' side of the transducer should be facing down with the point of the V facing toward the bow. Below is a graphic from Sternmate showing correct transducer orientation.
View attachment 19163

They have a really nice how-to web page showing the correct installation and orientation for a transducer.
http://www.sternmate.com/Where.html


I just went out and looked at it and you are correct!! The transducer was backwards, with the "V" facing backwards, I said Good Eye in my last post, now I will say very good eye!! and thanks for that. That might be the reason it stopped working at a certain speed of the boat. I knew positioning was wrong when it does that, but had no idea it was backwards. Thanks for the help on that!
 
Here are a couple more pictures of the motor position with the bottom of the boat:

IMG_3219 (Medium).jpg

from under the boat (yes, the ground was wet and cold, your welcome)

IMG_3221 (Medium).jpg

I hope that tells you something because it tells me nothing..... The bottom of the boat is about dead even with the top fin on the gear box..... Good or bad?
 
That looks about perfect to me. When you are in the water is the propeller fully submerged. If so I would have to assume the spray is probably coming from something on the boat. Either the boats bottom or that transducer.

As for the trim pin, you should position it on position 3 and then take the boat out. If it bobs up and down, at WOT, you probably want to move it to position 2 or position 1. If it doesn't want to get on plane, then position 4 or 5. If the boat moves well, then leave it where it is. You may also find that you may want to trim the boat (change the pin position) differently depending on how many people are in the boat.

Anyway, that is what that pin is for. I doubt any position will make the spray go away but certainly try 1, 3, and 5 and if the spray is still there, look for whatever is causing it, since you now know the trim of the motor is not.
 
The trim seems perfect now, the prop is under water (I should have shot a video off the back to see where it rode in the water)

The spray seems equal on both sides of the motor. I was looking at it today to see if there is anything on the bottom or back of boat and there was nothing, all seem normal. The lower end on right now is a lower end that I bought off EBay and rebuilt so I know what Im starting off with (I'll rebuild the one that came with the motor over time and have it as a back up). I noticed that the previous owner of this bottom end, had a hydrofoil installed and there are 4 bolt holes in the cavitation plate. I wonder if thats where the spray is coming from? Im going to put some small carriage bolts (rounded head facing down) in the holes before I go out again and see if that is the issue.
 
Here are a couple more pictures of the motor position with the bottom of the boat:

View attachment 19164

I hope that tells you something because it tells me nothing..... The bottom of the boat is about dead even with the top fin on the gear box..... Good or bad?
the anti-ventilation plate is the ‘fin’ just above the prop. That is the plate that should be just about even to slightly above the level of the hull. By your description your motor is setting too low. Try raising the motor 2 bolt holes on the transom then Re-measure. Use a straight edge against the hull and extend out to the lower unit to measure height. This is much better than the calibrated eyeball.
 
I have run these motors for many years (same leg and lower unit design). This picture shows me about 30 years ago with twin 30's, the boat is a Alumarine, made in Winipeg Manitoba. The transom design causes the spray you display because there is a slight conflict with the height of the "anti-cavitation plate" and the transom. You may need to make sure that the ACP is not causing this spray. Simply observe the boat in action, while on step. Your remedy will be to raise or lower the motors position on the transom ( as was already mentioned). My guess is that the motor is running too deep, brother. In agreement with Kevin. Maybe 2 inches approximately. Notice correct spray on this outfit. They, of course, are longshafts. Will include photo in next post....won't go through off this Android.
 
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I agree the cavitation plate is well below the bottom of the water level to bottom of the transom. I did some looking into what I can do about it, if thats the cause of the spray, and decided to live with it....... Based on what I read, It doesn't hurt anything, and the fix is a few hundred dollars in a Jack plate, but that will move the motor back farther and to me, is ugly...... I could make something to raise it, but rest assured, it would be ugly as well. The big draw back for me is the motor is not just clamped on, it also is bolted on. Moving the motor up would leave to unwanted holes in the transom and would create more, all for a couple MPH loss on the top end, which this is not a speed boat anyways, and a little water spray....... My thought is to live with it......
 
In total agreement with Tim pertaining to the cavitation plate. That type spray is called a "Rooster Tail" and is caused "only" by the engine being too deeply submerged in relation to the bottom of the boat.

The ideal setting for it to be is approximately 3/4" (no further) below the keel and parallel with the bottom of the boat.

Of course, any other object ie... pipes supplying water to bait compartments, transducers etc installed incorrectly will also create a similar but not an exact problem.
 
I went out and looked at what it would take if I were to raise the motor up. I noticed that the motor mount had 2 bolt holes and the bolt was in the top hole. I was able to raise the motor up about an inch which when I placed a board from under the boat to the gear box, I was about half way between the cavitation plate and top plate. To cold to take it for a spin (but believe me I want to). The next nice day I'll see if it made a difference.
 
I went out and looked at what it would take if I were to raise the motor up. I noticed that the motor mount had 2 bolt holes and the bolt was in the top hole. I was able to raise the motor up about an inch which when I placed a board from under the boat to the gear box, I was about half way between the cavitation plate and top plate. To cold to take it for a spin (but believe me I want to). The next nice day I'll see if it made a difference.

1 inch will (should) make a world of difference... I feel vindicated reading that the experts are confirming my suspicion described in my post #5 about motor height..... :)
Keep us updated on the result.
 
Your doing great, brother Dinghy. You may have mentioned it first of all. Another point to consider on motor depth......economy. Having the correct depth can make a significant savings on fuel consumption. Be sure to use non oxy fuel as well. The performance as well as economics......then add in fuel longevity, stability, and preserving rubber composition parts.....is well worth the higher price.
 
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1 inch will (should) make a world of difference... I feel vindicated reading that the experts are confirming my suspicion described in my post #5 about motor height..... :)
Keep us updated on the result.
Yep, that was a good call. The angle of the photos deceived me and it seemed the motor was okay. While the backwards installed transducer was a significant part of the spray, the low engine height was also a contributing factor.

1" higher will certainly make a difference, but having the antiventilation plate even with the transom is ideal. It seems on this hull a jack plate is the only way to get this exactly right, but as the OP said that's a lot of cost. I'm willing to bet the 1" higher mounting location will make enough difference for the OP to be happy enough to just gas it up and go have fun.

KJ
 
When we took it out last, we had 3 in the boat, usual boat gear, nothing else to speak of. We ran for almost 2 hours and my tank gauge went from full to one line below full, so between 3/4 tank and full tank (6 gal tank). I would say throttle position was mixed 50/50 from slow(er) to wot during that time. So economy is pretty good (? I think), or at least a lot better than what I had anticipated it being. Again...... A few MPH at wot slower, a little worse fuel consumption, and a little water spray won't be the end of the world if this little rise of the motor doesn't work.

Oh, I was hoping that I would have burned through all the fuel I had because I did use 97 - 10% ethanol, kinda by mistake........ but I did add some fuel additive. Wondering if a higher grade of clean gas would have any profound impacts?.....
 
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Its not so much the octane, but the difference in the power of combustion of pure gasoline over ethanol. Ethanol is actually an octane booster, but a poor version, that once it separates from the petrol fuel it cannot be remixed. The result is deterioration because the old ethanol has suspended moisture which pulls out beneficial additives and separates them from the petrol, further reducing octane. This will cause pre detonation, especially in 4 stroke equipment, causing potentially harmful results. Modern automobiles have sensors to detect and make compensation by richening the mixture, retarding the timing, and other measures to save the engine.....or at least try. The end result is poorer economy and potential oil contamination, causing excessive or lets say, undesired and unneccessary engine wear.
Don't take it from me, but I read all the literature put out by Amsoil.......and they don't sell fuel. They are completely and directly competing with the oil industry, yet they basically promote petrol while trying to create products to "protect" us from ethanol. The only reason most ethanol blends are cheaper is "tax breaks". Okay, end of today's lesson, brother.......believe it or not.......I HAVE TO TELL THE TRUTH........I GOT A BAD MEMORY!
 
Regarding "profound impacts"......not really. But, reliable, stabil, and confident performance. Here, try this.....go get some 15 percent ethanol and add 10 percent water. Put it in a glass bottle and shake it up. The ethanol will suspend its own weight in water. Then put it on a shelf, somewhere that has humidity.....like outside in a shelter......somewhere you might store your boat. Leave a small hole in the cap.....this is your fuel tank vent. Check it in a few months.....yuck. Would you put this in your outboard motor? Stabil can only delay the process for a short time. Remember, notice the seperation that is what will take 10 years or more for pure petrol to do.....not 4 to 6 months. The damper the environment, the faster the deterioration, as the ethanol "invites" the water.
 
I like and trust Amsoil. Thats all I ever run in my Goldwings (for oil). It has made a huge difference in how smooth the engine runs and the transmission shifts. Will never use anything else in my wings.
 
Right on, brother.....got it in my 83 Venture and also in the fuel.....front shocks too. Had that baby for over 25 years. Love it.
 
People say the strangest things, myself included. Jobe... You stated "I was about half way between the cavitation plate and top plate."

I read that a dozen times... Still don't know what it says! Reminds me of "Being halfway between here and there" :)

Where does that 1" put the cavitation plate in relation to the bottom of the boat?
 
People say the strangest things, myself included. Jobe... You stated "I was about half way between the cavitation plate and top plate."

I read that a dozen times... Still don't know what it says! Reminds me of "Being halfway between here and there" :)

Where does that 1" put the cavitation plate in relation to the bottom of the boat?
Joe, I think the 'Top Plate' Jobe mentions is the protruding part on the lower unit where it mates to the mid section. From the pictures it looks like this section of the LU is about even with the bottom of the hull. If I had to guess, I'd say moving up the next set of bolt holes still leaves the cavitation plate about 1 1/2" below the bottom of the hull. Not ideal, but better than it was.
 
Its not so much the octane, but the difference in the power of combustion of pure gasoline over ethanol. Ethanol is actually an octane booster, but a poor version, that once it separates from the petrol fuel it cannot be remixed. The result is deterioration because the old ethanol has suspended moisture which pulls out beneficial additives and separates them from the petrol, further reducing octane.
Tim I'm with you that ethanol containing fuel is not great in a marine environment. When it's available, pure gasoline is the best option for any boat engine.

Myself, I'm in a real conundrum because even though I have a few lakes around me, I'm also in the middle of corn country and have yet to find a gas station where I can find non-oxygenated fuel. For me here in central Illinois, I simply use Stabil 360 Marine in every tank of fuel, whether it's an I/O engine, outboard, or jet ski. No, it's not a perfect solution, but so far I haven't had fuel related issues in any of my boats.

So, if Jobe has 100% gas available, then that's the best option. If not, using Stabil 360 is the next best thing.
 
Good advice. Overall we have messed up our fuel but helped the farmers, hurt the consumers, and kept me in the repair business......but I still don't like the whole, overall picture. I'd rather do repairs that are brought on by normal wear and tear, accidents........., or stupidity.
 
Joe, I think the 'Top Plate' Jobe mentions is the protruding part on the lower unit where it mates to the mid section. From the pictures it looks like this section of the LU is about even with the bottom of the hull. If I had to guess, I'd say moving up the next set of bolt holes still leaves the cavitation plate about 1 1/2" below the bottom of the hull. Not ideal, but better than it was.

Your guesstimate is exactly correct. It's a flat bottom fishing boat thats never going to break any speed records, I'd love for it to be correct, but if it isn't it isn't.... The PO was the only owner since new, and it's been this way all the time he had it....
 
OK....... Still thinking about this...... it's what I do....

If I get something like a Vance JPL2412SB Jack Plate https://www.vancemfg.com/product-p/jpl2412sb.htm I like the product, I don't care for the setback because Im thinking a few things...... Linkage? Motor controls will be ok but will steering linkage go back 5" and still operate ok? It will now be hanging outside the back of the boat. Also, speaking of hanging off the back of the boat, how much effect will moving 160 pounds (roughly, with the added jack plate) back 5" have in my boat position on the trailer? Will I have to move the boat forward 2 to 3 inches to offset the weight change?.......

I wish I could find one like this with only a 2 or 3 inch set back...., or I wish one of you guys were my neighbor....... Of course you'd be afraid to leave your house......
 
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