prop selection on 22ft pontoon

[raceweld]

I am helping a friend out on his pontoon boat,He had complained that the motor,a df 90 a Suzuki was acting like a dog and he could not get it to run correctly.He took me for a short ride and in the short ride I found a fuel issue as the boat would surge an pop.Upon lifting the cover I found an incorrect fuel filter and a twisted and pinched fuel line.I repaired that and took another short ride.The motor ran fine after it was getting the proper fuel supply,however the motor was laboring and could not get above 4100 rpms.My friend was disappointed as he thought the fuel issue problem would resolve the poor performance.I started to pick his brain about when this started.I found that a family member had hit something last fall,and he had to replace the prop.He had gone to a fellow who rebuilds prop and he got a good deal on a stainless steel prop which he was told was a better prop than the one he had,which was aluminum.
When we got back to the dock he showed me to old prop.That prop was a 4 blade aluminum,13-x-15 by solis.I climbed in the water and removed his prop the was on the boat and found two things of interest.First the prop on the boat was a 3 blade stainless steel prop,-13 1/2-x-19-k.The second thing I found was the prop shaft was slightly bent with about a 1/8 inch wobble.
upon further questioning I found he had bought the boat from a local marina,and then the motor from a dealer 50 miles away who is no longer in business.
My questions are,what is the correct prop for this pontoon boat,and where can I get a prop shaft for a DF 90 A?

 

[crb478]

Re: prop selection on 22ft pontoon

a four bladed 13 or 15 pitch is probably about right for that boat, The prop shaft will also need to be addressed. The stainless prop is way to big and will need to be replaced. You may also want to check the motor height, it may need to come up if the 3 bladed stainless is not blowing out.

 

[lakegeorge]

Re: prop selection on 22ft pontoon

I'm sure others on here with that motor will chime in on prop size. Don't buy a ss prop, the Merc Black Max Aluminum will work just fine and save a few hundred dollars. I would go with a 3 blade also.

 

[belairbrian]

Re: prop selection on 22ft pontoon

So was he happy with the performance prior to replacing the prop?

If so, go get the same size/pitch prop.

 

[WaterDR]

Re: prop selection on 22ft pontoon

Thats the wrong prop for sure.

 

[raceweld]

Re: prop selection on 22ft pontoon

Thanks Guys,

After a day on the water yesterday we got some of the issues resolved.In the conversation I had with the boat owner during several short test runs I found out several pertinant facts.The gas that was in the tank was from the first year he had the boat,three years.I was unaware of that because when I changed the filter the bulb and line was empty.After I found this miner fact out I drained the fuel tank of about 10 gallons of varnish and replaced the fuel.While on a test run the motor popped a few times and started to run better,but still not good.A trip to the parts store and some plugs and a bottle of injector cleaner later the motor ran great.We had found on the way to the lake a prop repair shop and picked his brain.This was not the same shop where he had bought the other prop,but a local shop to the lake.He checked the prop and found that it was not a 19 pitch as it was marked,but a 17 pitch.He also gave us a 15 pitch to try.We tried the 15 first and the motor ran up to 6000 RPM.We then put the his old one back on,the 17 pitch and the boat now ran great and topped out at 5600 RPM and planed out well.
Amazing what a few "extra" facts can do to figure out a few issues.
In order to resolve the prop shaft issue,what is needed in order to remove the shaft.Is there any special tools or pullers required.

Thanks for all of the imput,the information is great.The website is super.

Patrick