SS188 Prop Ventilation

garrett575

Hello group.  I just passed the breakin on my SS188 with Yamaha F150.  While "horsing around" and during tight turns experience prop ventilation.   I have not owned a boat in many years and my previous boat was a 16' with a  90hp outboard.  I was able to make tight slow turns to create wake for tubers.  When I try this on my 188 the prop ventilates and I cannot get any speed to hit the wake. Does anyone else experience this?  Suggestions on preventing this.

TNriver

Its funny you posted this today. I just ordered a new prop today for the same reason. I asked around the last 2 years and could not find anyone with a SS188 / F150 combination that had experimented with props other than the SS Reliance 17" pitch.

Several people with similar boats went with 15" pitch 4 Blades like Power Tech with pretty good results; however their boats were a little larger and slightly heavier. I have no problem hitting the rev-limiter on mine even with a decent load, so I wanted to try something a little different.

I am currently running the SS Reliance SDS 17" pitch 14.25" diameter prop.  After talking to several different prop shops and calling Yamaha, I decided on a Turbo 2+2TH in a 16" pitch. It is slightly smaller in diameter at 14" versus the 14.25" Reliance. It seems I am looking at a 2 week delivery, since the manufacturer would not sell direct.

The main reasons for switching props:
- Reducing blowout in turns pulling a towable
- Reduce minimum speed to stay on plane

I have had great experiences with Turbo 1 props in the past, I will see in a few weeks if this is a good setup or not.

On another note I am running a SE300 hydrofoil that helped with planning and turns.

Ernest_T

Are you trimming fully down on the sharp turns?  My 217 SD with a Yamaha F150 will always ventilate on sharp turns unless I trim down.  If I trim down, I can take some pretty sharp turns without ventilation.  

I also switched to a 4 blade Power Tech prop to improve hole shot and for wake boarding, etc.. I also noted less ventilation with this prop in the turns, but I still have to trim down.  

TNriver

I always pull a tube or towable with the trim all the way down on the SS188.  I have owned and worked on numerous boats, and the SS188 ventilates pretty bad in comparison to other outboard powered boats.

If you start cutting the boat trying to make waves or manipulate a tuber, be prepared to manage your throttle. This weekend I got up on plane in a straight away and then proceeded to make a gentle sweeping turn while moderately accelerating with 6 people. I had to back off the throttle because the Reliance prop started to blowout.

We will see how the Turbo brand works out.

garrett575

Thanks for the help.  I have a Reliance SS prop right now.  Not sure of the pitch and diameter but it does allow me to get up to about 6000-6200 RPM.  When I experienced ventilation I had the trim all the way down.  I ran for a few minutes with the trim in the middle to get the bow up and some good wake behind the boat.  I then lowered the trim and attempted to turn into the wake but the prop ventilated and I had to throttle all the way down before I could move forward again.  I think for now I will try a SE400 Hydrofoil and see how that works out.  I have not yet pulled a tube as the water temp is still below 60, and I have not worked it too hard because I was still in the break in, and my wife was with me most trips out!  I also want to check the mount the next time I am at the lake.  I know the motor is mounted in the second hole, but I believe the mount sits about 1" above the transom.  I will take a pic next week and post here for some opinions.  

garrett575

How does this mount location look?  TNriver, looks like we are mounted in the same hole location, but your mount looks to be lower than mine.....

TNriver

garrett575 your F150 is mounted one hole higher than my setup. This probably explains why you are having more of a problem. Nice boat!  I wish my boat had the stainless bimini top option. My boat came with everything upgraded to stainless except for the top. I have converted the nylon mounts to stainless on the boat already and plan on purchasing the stainless bimini frame here soon.

TNriver

The Turbo 2+2 TH 16" pitch worked great this past weekend. The boat holds the tight turns now and the hole shot is even better. WOT is 6000 @ 43.8mph versus 6100 @ 45.7mph with the same decent load and full tank. I can hold the boat on plane at 16mph versus 19mph before. (GPS not speedo) I even noticed a little better control while docking.

I would highly recommend this prop for the SS188 with a Yamaha F150. The overall performance is better.

garrett575

Glad it worked out for you.  I'm still playing around but I have had some success keeping the trim down and easing into the turns.  I hit 49 MPH on my GPS with one on board and half a tank.    Still might try a hydrofoil and maybe a Turbo 2+2 next year.  Thanks for the info.  Happy boating.

TNriver

Here is a picture of the Turbo 2+2TH 16" pitch mounted.