Jack M
Moderator
No apologies necessary, might be time to check out a Bennington.
Motor Height and Water pump intake at WOT ??
- Thread starter Canufixit
- Start date
Jack M
Moderator
Have you checked with Mercury?
Here is their number, 920 929 5040
Here is their number, 920 929 5040
Lovely Boats!!! Been on Fresh water all my life (Small lake in New England). I'd love one !!!!
I got so involved - I forgot too ... I'm going to collect some more tests/data in the next couple days and then I'll call and post any findings. I WILL Post my findings and any help I can be to others here ...
Angela & Michael
Well-Known Member
From what I see in the photos, your engine is too high and too far back. Almost a design/engineer flaw.
Jack M
Moderator
The OP has not posted any pics of his set up yet .
DVW
Well-Known Member
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The photo that you referenced is of my modified boat. It shows cooling flow coming out of the indicator indicator and a slightly visible (so called) anticavitation plate. My repositioning of the single motor to the position shown allowed the boat to go 46% faster.
That's nice setup you have !!! I agree with what you said ... to clarify "my" point ... Mounting as You have done now insures that you have a reference surface to set the motor height. The Bottom of your pontoon is now in a position similar to the transom of the back of a boat. Mounting so your cavitation plate is at our just below the bottom of the boat transom.
With mine "hanging" between my 2 toons the passing surface water height will depend on how "deep" the toons run when at speed. Therefore I need a helper to run the boat at WOT while I observe and take pics. He's traveling and not here at the moment (Of Course, that's how it always works, right !) . I'm so aggravated with this, and the fact that I'm in NE and it's time to pull the boat before It gets too cold for maint/storage/winter covering (Come fast here !!) I'm just thinking of Pulling my toon out and doing the following....
- Put a Call into Mercury for assistance/discussion.
- Do Full Maint for year/100 hour service. Motor has about 730? hours at low speed,
- Replace the Pump Impeller (I'm 99% sure it is fine due to low hours). And, I normally run at 1.2K for a nice quiet cruise).
- IF I can drop the Motor to the final hole mounting - I will.
- I have ordered a 4 blade OEM. Merc website. says the 4 blade is best for a pontoon to fix this problem.
- Store it until Spring ...
Today-ish , I'll at least get some pics of the back of the boat at the dock showing Depth of motor and cavitation plate at rest.
Thanks all for ALL your inputs so far ... Nice to be able to bounce ideas around.
With mine "hanging" between my 2 toons the passing surface water height will depend on how "deep" the toons run when at speed. Therefore I need a helper to run the boat at WOT while I observe and take pics. He's traveling and not here at the moment (Of Course, that's how it always works, right !) . I'm so aggravated with this, and the fact that I'm in NE and it's time to pull the boat before It gets too cold for maint/storage/winter covering (Come fast here !!) I'm just thinking of Pulling my toon out and doing the following....
- Put a Call into Mercury for assistance/discussion.
- Do Full Maint for year/100 hour service. Motor has about 730? hours at low speed,
- Replace the Pump Impeller (I'm 99% sure it is fine due to low hours). And, I normally run at 1.2K for a nice quiet cruise).
- IF I can drop the Motor to the final hole mounting - I will.
- I have ordered a 4 blade OEM. Merc website. says the 4 blade is best for a pontoon to fix this problem.
- Store it until Spring ...
Today-ish , I'll at least get some pics of the back of the boat at the dock showing Depth of motor and cavitation plate at rest.
Thanks all for ALL your inputs so far ... Nice to be able to bounce ideas around.
Attachments
Does your Sun Tracker pontoon, feature a small fabricated aluminum "V" bottom in front of your engine? If yes, you would then set the engine height based on that "V" with the engine cavitation plate even or just below it. We are not talking about a performance application here so no need to worry about engine height to go faster. Once you establish where the engine height is relative to the "V", you can decide where the engine height needs to be. Is your engine a Bigfoot (Command Thrust) or standard gearcase?
My 2 toon does have a "splash" ? Plate under the engine it's a ramp that attaches a couple feet in front of the engine on the bottom side of the floor and drop down as it ends at the end of the boat. There is a funny "V" attached to the bottom center end edge. Guessing here, Alu piece welded? in place. 3/16" thick v 1/2" wide and 3"? inches long. Looks to be intended to be a water diverter ?? When stopped this feature is a few inches above the water ? This appears to be MUCH too high for the cavitation plate height - at least on mine. Again I need to get pics Today and post. (My Kitchen sink lower drain line - and 2" 65 year old Cast Iron beast rusted shut and I'm writing checks for my plumber right now and cutting holes in my wall)
Yes this is a long shaft Command Thrust lower unit.
I'm going on vacation soon and need to pull this out for maint/storage. I'll advise ... THANKS ALL !!
Yes this is a long shaft Command Thrust lower unit.
I'm going on vacation soon and need to pull this out for maint/storage. I'll advise ... THANKS ALL !!
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I forget to add in my password for this account into my password manager. I have 2 PCs and the other I rebooted for upgrade and now cannot log in that PC. THIS PC I can still use.... as I have not logged out. And, I can't change my password online as it wants my old password to change to a new one. On my other PC I checked - "Lost password" at login and requested a reset mail - but it nothing has arrived. Should I get lose access to this site I'll have to make a new login and I will advise here when I have done so. Always something to fix ....
Jack M
Moderator
Some work is being performed on the site currently . I'll notify the operator .
I was expecting my new 4 blade Mercury New OEM Spitfire 4 Blade Prop 13.8x10 Propeller 48-8M8026555 Pontoon today - but it had not shipped - contacted store ... Oh, he can't find it ... SO I reordered from Leaders RPM (my go to for quick ship and fast delivery). I wanted to do quick swap on the props and see if it made a difference before I started changing anything else ... Sigh ...
Jack M
Moderator
I spoke with the site operator, your password reset emails have been sent . He asks that you check your spam .
Thank you ... but no good. I have received nothing and checked my Spam, Nothing. I also tried to reset it again on my "not logged in machine" and it did say it sent me a reset Email - as before - but I have received nothing. Perhaps it's because I'm logged on on my other PC ?? But If I log off - I'll not get back on ...
I have some pics and measurements - but NOT of WOT and the Cavitation plate position in water. I did not want to leave the helm until I at least rig up an extension to the kill switch.
Note: All pics here are at rest at the Dockside. Boat is normal load except for me. These pics are to show my current mount/setup and ref to my measurements. Motor tilt is straight up and down (Almost full down/in). I took these pics and measured while standing behind the boat in 5 feet of water.... So best possible measures on non flat stuff. ....
18' pontoon boat 2000.
Toons - qty 2 21" Diameter
My center "wedge" under the toon center before the motor - back edge is 4" under water.
Wedge bottom is 11" wide.
Distance from the water surface to the top of the cavitation plate 11"
Cavitation plate is 7" under center wedge lip.
Hole pitch for height change is 3/4" between holes and I have one more hole I CAN drop the engine - one hole more from what I can tell buy spacing left in motor adjustment.
Toon bottom to water surface is 13"
Distance between toons - 56"
Pics on next post (I have to get them swapped from my phone to this PC to post.)
Note: All pics here are at rest at the Dockside. Boat is normal load except for me. These pics are to show my current mount/setup and ref to my measurements. Motor tilt is straight up and down (Almost full down/in). I took these pics and measured while standing behind the boat in 5 feet of water.... So best possible measures on non flat stuff. ....
18' pontoon boat 2000.
Toons - qty 2 21" Diameter
My center "wedge" under the toon center before the motor - back edge is 4" under water.
Wedge bottom is 11" wide.
Distance from the water surface to the top of the cavitation plate 11"
Cavitation plate is 7" under center wedge lip.
Hole pitch for height change is 3/4" between holes and I have one more hole I CAN drop the engine - one hole more from what I can tell buy spacing left in motor adjustment.
Toon bottom to water surface is 13"
Distance between toons - 56"
Pics on next post (I have to get them swapped from my phone to this PC to post.)
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Jack M
Moderator
I sent you a PM .