installing new engine on pootoon

[oojacoboo]

Ok, I need some help on installing a new engine on my pontoon. It is a 21' or so pontoon boat. My questions are, how do I determine what motor shaft length I need. What is considered to be the keel base? How do I measure it from the top of the transom so I will know. What do people generally use for a gas tank? Where do people install them? Any other tips on installing an engine on a pontoon would be greatly appreciated. Thanks.

 

[rickdb1boat]

Re: installing new engine on pootoon

You can bet you need a long shaft motor(20" leg). Standard on almost all toons. If there is no built-in gas tank, a couple of 6 gallon portables(Available at Walmart) are the answer. There are strap kits available to secure them to the deck. ( A little tip before you install the tanks is to look inside them and make sure there are no plastic shavings from the drilling process at the factory. These can clog your fuel lines and/or filter) Before I got a toon with a built-in tank, I had 2 portables hooked up to a 3-way gas valve, and then on to the motor, to make it easier to switch between tanks when one went low or empty. It depends on the configuration of your toon as to where you mount them. Most times they are on a platform on the back. When you install the motor, move it to the far left on the transom for starters, so as to make it easier to install the steering rod into the tilt tube. Then center the engine and/or match up with the existing holes in the transom.


http://www.iboats.com/mall/index.cgi?keywords=3%20way%20valve&session_id=552099377&cart_id=110423646&list_time=1152635178&view_id=2941 ] 3 way valve[/url]

 

[Silvertip]

Re: installing new engine on pootoon

Depending on how large the body of water is that you will run on, you may want a larger fuel tank. Normally the back of each "toon" has a pad on which to mount portable tanks. Check for "fuel tanks" on-line. There are many shapes and styles of square and rectangular tanks that provide more than the six gallons the typical portable provides. That does complicate refueling but if you get fuel at a marina its a non-issue.

 

[oojacoboo]

Re: installing new engine on pootoon

I was thinking more like buying a large 20 gallon or something that would fit under one of the rear seats. I was hoping there is such a thing. I live in Charleston, SC, so it would be riding around on rivers and such. The need for a larger tank is pretty critical.

As for the "leg", I was thinking a 20", but I actually measured from the top of the transom to the prop that is on the electric outboard installed on the toon at the moment, and it came out to more like 25". This is probably a waaaay off measurement, but, again, I am unsure on how to go about measuring a transom to keel length on a pontoon.

what HP rating motors do you all use on your pontoon. I was thinking I need something >70 HP, as I have to calculate the current and such around here. But, many people say they do fine with 50HP, I just don't know.

Thanks,
Jacob

 

[rickdb1boat]

Re: installing new engine on pootoon

You could put a 20 or 30 gallon under the seat or wherever you can get it. Plenty of them out there. Just check iboats, cabelas, West Marine, Etc. I run a 70 rude on mine. You may want more. What is the maximum HP the boat is rated for? I get 22 MPH on mine. You could hang a 100 HP on the back and get maybe 24-26 MPH.

BTW-What brand toon are we talkin' about?? Year?

Here ya go:

http://www.overtons.com/modperl/overtons/detail/pdetail2.cgi?r=detail_view&item_num=36867&fcat= ]Tank [/url]

 

[oojacoboo]

Re: installing new engine on pootoon

nice, thanks for that link.

Its an mid 90s model Riviera Cruiser - Tracker. I don't really know how long it is. I don't even know where to measure to find this out. Do you measure the toons or the "platform" itself?

I don't know what the rating is, I need to check that out. Any ideas on how to measure the length of the transom to keel on a pontoon? I need to find out if I need a 20" or 25". Thanks alot.

 

[rickdb1boat]

Re: installing new engine on pontoon

Re: installing new engine on pontoon

You can measure the platform and get close. As far as the transom, the cavitation plate on my motor is about 2-3 inches higher than the bottom of the logs. And I have a 20" lower unit. On that year Rivera, it will take a 20" lower unit. My sis-in-law had one awhile back. Only the newest toons with 3 large logs take 25" shafts. Be aware, those Rivera's do not have the strongest transom supports. Hers damn near fell off with an 88 HP on it. Had to do all kinds of reinforcing to beef it up and then she sold it.....

 

[tashasdaddy]

Re: installing new engine on pootoon

you still need to find out the max rating. told you you'd get better results. good luck

 

[Silvertip]

Re: installing new engine on pootoon

I can't believe a 21 foot pontoon needs a 25 inch motor. Place a 2x4 across the bottom of the two pontoons and then measure up to the top of the transom. Since the pontoons will be at least 1/4 of their height below the surface of the water, those figures should allow you determine whether a 20 will work. I've never seen a pontoon that needed a 25 inch motor (at least an average size unit that is).

 

[oojacoboo]

Re: installing new engine on pootoon

hmm, I actually found a 115 horse motor that I was thinking about putting on the toon. Maybe I need to looking into some welding support... I will check out the max rating tomorrow.