Jim Swope jr wrote:
I just bought a 1971 Glastron V-170 Crestflite and it came with a 1983 75
horse Evinrude. The markings on the prop say 13-1/4X17.
The engine seems to be running fine at high and low rpm's.I cant hear any
missing. It cruises nicely at low rpm's but when I give it full throttle It
sounds like it is at full
throttle, im getting about 2500 rpms if I remember right. Also with the
cover off and manually holding the throttle at full bore I can only get
about
eight miles an hour out of it according to my hand held gps. At any rate it
goes pretty slow and Im not sure why. Is this engine too small for this
boat.
The recomendation for this boats says not to use any bigger than 125 horse
so Im thinking 75 should be sufficient.I've tried adjusting the plane in all
different positions but dosnt seem to matter much
and get no noticable increase in speed. Any suggestions would be happily
appreceiated.


Thanks.... Jim




The engine size is fine for that boat - you might want more to pull
skiers, tubes, etc. but it should go at least 30mph with a light load.

You did unhook the trailer, right?!

It sounds like the hub is spun (Google "spun hub") but that doesn't
explain the low RPM's. Since you say it sounds like it's revving higher
you may have a bad tach, too. Before you take the propeller to a prop
shop, buy a cheap aluminum prop of the same size and pitch. You should
carry a spare anyway.

If the RPM's are correct and you are getting 2500 at WOT, you probably
need a good carb cleaning. A bad stator will also cause that problem
but the carburetor is more likely and a lot less money to repair.

One last thought would be that the boat is taking water in the bilge and
weighing you down. You did put the plug in, right?!