3.0 alpha rpm question

[pontotoc1]

I have a '97 3.0 alpha. I don't know the speed I'm getting because the speedometer doesn't work. I just bought the boat and it seems to run fine, but I would like to get a little more speed. The tach shows 3000 rpm at w.o.t. I guess that I'm doing around 20-25 mph. Does that sound normal?

Thanks

 

[mkast]

Re: 3.0 alpha rpm question

Engine is a tad low in RPM.

 

[pontotoc1]

Re: 3.0 alpha rpm question

Can you tell me what I should check first? Could this be a throttle problem, or possibly need another prop? I thought that maybe I should check throttle linkage and see if maybe it needs to be adjusted. When I accelarate it seems that the first few inches that I move the throttle nothing happens. Only after I get to what I would consider 1/4 to 3/8 open do I get any engine response. The guy I bought the boat from said that he cruised at about 2600 rpm. I thought that it seemed a little low. Also the prop looks like it has been replaced. Could he have put the wrong size back on?

 

[Jerico]

Re: 3.0 alpha rpm question

A bit more info would be helpful. What size boat, and what prop do you have on it? My boat is 17'6", and I have a 14 1/2"/19 pitch prop. It will run up to just under 5k rpm and about 42 mph. If I remember correctly WOT on mine is 4700 rpm. When I bought it the prop was a 14"/17 pitch. Top speed was about 35 and it seriously over revved the engine.

The 17p I rarely use gives a better hole shot pulling a skier, but I have to be VERY careful watching the rpm's. The 19p keeps my rpm's down, so I run it 99% of the time. I generally cruise at between 3000-3500 rpm and 24-27 mph.

Hope that helps at least a little.

 

[pontotoc1]

Re: 3.0 alpha rpm question

I will look at the prop tonight and see if I can figure what is on it. The boat is a 24' fisher pontoon. I may be getting all the performance possible now. This is the first pontoon I have ever owned. I just feel like I'm sitting still and hoped that there was a way to gain a few more mph.

Thanks

 

[Jerico]

Re: 3.0 alpha rpm question

You might also try posting your question in the pontoon area http://forums.iboats.com/forumdisplay.php?f=409 and see if anyone there can give you a better idea.