prop or enguine problem

[kcseasprite]

here's my info: Model 1977 1782 Cougar BR, made by sea spriteby united marine. Lenght: 17"4ft, beam: 82", weight 1150lbs dry, type: runabout / Tri hull, max capacity: gear, boat, motor 1700lbs. trans height is 20" max horsepower power rating is 130HP. My motor 1977 115hp mercury, final drive ratio: 2:1, Max speed acheived 25mph with paddle wheel attached to hummingbird 565 fish finder. This run was with me in the boat with my normal gear and about 7 gallons of gas. I weigh 150lbs so total weight with just me in the boat at full throttle should be about 1800 - 1850lbs. The prop on the boat now is a factory mercury prop 4865024 A1 19P. I do not have a tach. Please help.

 

[QC]

Re: prop or enguine problem

Something isn't right for sure. You must have a tach to do this. Use a Multi-meter or something. I am getting less than 3500 RPM at 20% slip with your numbers which is waaaaay too slow and I don't believe she would get on plane if the engine was that sick. While I like paddle wheels, you are so far off I don't trust any of the numbers.

 

[kcseasprite]

Re: prop or enguine problem

The boat was able to get on plane. no sputtering or bogging. I do have a volt meter / multi meter. where do i connect it and i'll try to get a hand held gps. Any reply's would be apprieciated.

 

[kcseasprite]

Re: prop or enguine problem

Oh, I also do have a car tach. Will this work?

 

[QC]

Re: prop or enguine problem

Yeah, I am not clear on how you hook up either to get a correct reading on a two cycle. Post that in Non-Repair Outboard and specifically mention two cycle. I think you'll get your best responses there on the tach question. Yes, GPS and correct RPM are must haves. Good luck!! We can definitely help more with that info.