posted 01-22-2002 01:53 PM ET (US) I just got a 1996 Johnson Ocean Pro 90hp this weekend. It has a 17 pitch SS prop. My old engine (1985 Evirude 115) has a 21 pitch SS.
Three questions. Will my old prop fit on the new motor? Which one would be the best? I think a 19 or 20 is really what I need. Can either of these be bent to a 19 or 20?
Bigshot
posted 01-22-2002 02:42 PM ET (US)
Dan, yes it will fit. How many RPM's are you doing now? I believe that new 90 is 5500 redline(double check) so if you are there......enjoy.
If you are over the red by 100-200 you can have it double cupped which will add about 1" of pitch. If you are blazing through redline and know your tach is acurate, try the 21 but most 90's run a 17SS but maybe a 19 if always with a light load. 21" will be too big. My 1985 115 ran a 19" SS and was perfect.
Whalerdan
posted 01-22-2002 02:54 PM ET (US)
Thanks. Haven't been out on it yet. Should be installed some time this week. I'll try the 17 first.
TightPenny
posted 01-23-2002 10:26 AM ET (US)
I use a 17" Michigan Wheel SS Rapture on my Montauk with a 2001 90hp Ocean Pro. Lightly loaded (excluding me) it runs around 5300. 5500 is red line.
A 21" pitch would never reach full RPM
Wild Turkey
posted 01-25-2002 10:22 PM ET (US)
Tight, I bet with a jackplate it might. Didn't one of Clark Roberts' 17's run a 23 pitch with a Merc 90? Granted... those Mercury 90s were fast!!!!
Bigshot
posted 01-28-2002 11:28 AM ET (US)
Not with a jackplate. You can't gain 4" of prop by raising the engine. If you do you are just cavitaing and not getting any performance gain.
Wild Turkey
posted 01-28-2002 04:23 PM ET (US)
Nick:
I'm thinking about a plate. How did you lift the engines during your swap?
Chris
TightPenny
posted 01-29-2002 10:08 AM ET (US)
I use a 1-1/2 ton Yale Chain hoist in the garage in Seaside. It was free. A come-a-long would work as well.
Bigshot
posted 01-29-2002 10:22 AM ET (US)
Depends on what kind of access you have to lifting utensils. If you have a sturdy tree, a come-along works great. If you have I-beams in your garage...ditto. If you are like me and have nothing to strap a chain to that is high enough, rent an engine hoist(cherry picker) from Taylor rental, etc. $20 a day I think. Do you have boat davits? Know somebody with a garage(lifts work well too), etc.
Wild Turkey
posted 01-29-2002 10:30 AM ET (US)
Nick & Tight: I have a garage and a come-along (rated for 2000 lbs.- plenty). I guess what I am asking is.... did you use a strap around the engine?
They make an eye that bolts to the flywheel on my OMC. Should I buy one of those? (approx $45)
Chris
TightPenny
posted 01-31-2002 06:04 PM ET (US)
The 90 has two lifting attachments on either side of the engine head. I was lazy and used a rope through the two of them to form a yoke. The edges are sharp so watch the amount of swinging that you do so that you do not cut through the rope, or get the appropriate hardware to make the attachment.
Bigshot
posted 02-01-2002 10:46 AM ET (US)
You should have lifting eye(s) on it somewhere. My 90 Yamaha only had one eye. My 70 4S has 2. If no eye(s) then try and borrow the flywheel eye from a mechanic.
where2
posted 02-01-2002 12:36 PM ET (US)
Agreed on the Car Engine Hoist. Used it to hold the 70Hp OMC while installing the Power Trim & Tilt guts. Agreed on the davit too, Used that to swap several engines including the 50Hp 4Stroke Yamaha. Used the Come-Along off a rafter in the garage before...