Pontoon too slow!

[Chris20]

The jack plate would lower the engine more? How much lower would it need to go? When I tilt the engine up now a little bit of the bottom of the shaft is already in the water.

[Chris20]

You can see it a little here.

[MH Hawker]

It depends on what jack plate its self, I have only owned one and it allowed a 4 inch drop.

[Bamby]

We or at least me can't actually determine weather the OP's motor actually needs dropped from the angle of the photo's. What would be maybe helpful is a photo of the motor trimmed down and a photo taken from behind on a level plane with the cavitation, or anti ventilation plate or the plate directly above of the motors propeller. The plate should be more or less level with the bottom of the transom itself. If it's higher ventilation may be the problem and if it's actually low enough then maybe something else under the boat will become apparent or viable.

[Chris20]

Should I start with a 4 blade prop and if so how do I find the pitch. Maybe 13x15?

[Chris20]

I will pick the boat up tomorrow or Saturday I can take pics then.

[Chris20]

Going by the picture on the first page it appears to be lower than the transom!

[pond tuuunes]

Put a big block in it, it will go faster

[ToonGuy]

The plate should be more or less level with the bottom of the transom itself.

Not true on a 2 log pontoon. WAY too many variables affect the height of the cavitation plate in relation to the surface of the water. That would be true only if we were dealing with a 3 log tritoon with the transom built in to the center tube.

[MH Hawker]

Because of the turbulence between the toons it is very hard to pick a point that's deep enough, while a 20 inch long shaft motor is standard on must toons their is still motor weight and pontoon flotation heights to deal with. So sometimes you just have to drop it lower till it hooks up in clean water.

[Chris20]

A prop calculator I just used said I should use a 14 x 11 and I have a 13 3/4 x 13 would that make a difference or not until I get it to bite?

[MH Hawker]

Prop calculators don't necessarily work especially well with pontoons. Due to the different types of hulls. right now your at 5500 and that I believe is within your max rpm range. Going from a 13 P to a 11 P would raise the rpms, but it may also help it hook up. Sadly because of so may variables it is often trial and error. It is sure worth a try, especially if you don't have a spare prop, going to a 11 P should raise the rpms about 400 plus but it may be a lot more.

I experimented with motor height last year and while I am just using a little 9.9. the same principles apply. I am on a limited hp lake. I surly wanted ever bit of speed I could get out of it

I started out at 7 mph and 4000 rpm and dropped it down 2 inches and it went to 10 mph and 4800 rpm, so I cut off 2 inches off of my plywood transom and got it up to 12 mph and 5400 rpm. Just dropping it down into clean water made a huge difference. I sort of enjoy passing people I know are running remarked 15 hp motors. Altho a few weeks ago the WV DNR did a surprise motor inspection and busted over 75 boats, snickers, 40 plus were impounded.

[Chris20]

The prop sight emailed me a corrected prop of 4 blade 13.25 x 15 or 3 blade 14 x 15

[MH Hawker]

From what I understand a 4 blade prop is more for hole shot than top end, I have used them and it dose make a lot of difference on getting ever thing moving but in my case I lost some top end.

[GXPWeasel]

From what I understand a 4 blade prop is more for hole shot than top end, I have used them and it dose make a lot of difference on getting ever thing moving but in my case I lost some top end.

I've found this to be true as well. Four blades are meant for acceleration, not top end. I think you're cavitating, and need to fix that part first, before you buy another prop. My $0.02