Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: checked speed on the 13 today with GPS

Posted by rfuerst911sc on 09/01/13 - 10:39 AM
#1

I have only had the 13 footer in the water once since I completed the restoration. Hull is a smirked style of 1972/73 vintage not 100 % sure previous markings are gone. Anyway it has a 1987 30 Johnson with an aluminum 3 blade prop that I think is an 11 pitch ( going on memory ). Today I took my son and two grandchildren out for some fun on the water. Total passenger weight was around 430 lbs. plus a 6 gallon fuel tank that was full and another 6 gallon tank that was half full. One starting battery near the transom. One anchor, a few ropes and life jackets. The motor has the flat plate ( forgot the name ) aprox. 1 1/2 inch or so above the bottom of the boat. At full speed we hit 29 mph which I thought was pretty good with that load. I do feel some prop slip but only for maybe 5 seconds and then it grabs and gets up on plane. Unfortunately I do not have a tach so engine speed unknown. I will get a small tach just for checking for correct prop. So how does this sound compared to other 13 footers ? I think I'm in the ballpark but I believe I will probably be able to go up a little on the pitch and possibly go with a 4 blade prop. Any advice is appreciated.

Edited by rfuerst911sc on 09/02/13 - 4:52 AM

Posted by chrepp on 09/02/13 - 5:05 AM
#2

That sounds pretty close to me. I have a 1985 Tohatsu 30hp on my 1968 13' and get the same results with two adults and fishing gear. The cavitation plate is the name of the plate. I have never looked at what pitch my prop is. I only go in fresh water. Enjoy.

Posted by jhuchingson on 09/02/13 - 7:58 AM
#3

1968 13 SS - I have a 45 hp 2 stroke 1987 Mariner engine and usually have 600lbs on board - me, 3 boys, wife, dog or another buddy and a few kids etc. I also have a 12 gallon fuel tank and a single battery [when not fishing] - I get to just about 28-29 with 13p prop or 30-31 with 15p prop - with my usual load and since when were not fishing were tubing....I found the 13p prop is great on this boat. The 15p prop didnt produce enough lower end rpm's, hole shot to slow, always worrying about who's sitting where etc - This is at sea level and im anxiously waiting to see how the 13p does at altitude - 5,500ft where we have a cabin/lake - the 15p barely even got us across the lake at altitude unless we all sat in the bow and my 8 yr old drove the boat. Another member had suggested the 13p prop to an earlier post I made - he was spot on.

Posted by davebwm on 09/02/13 - 2:01 PM
#4

I have a 1969 13 ft Sport with a new Mercury 25 hp (four-stroke). Nor sure if the engine is fully broken in yet, but I checked it today with my GPS and got 27.4 mph top end with just me (about 210 lb) and essentials in the boat. Prop is three blade with pitch of 11 or 13 (different people at dealer told me different things and I haven't checked it).