Completed The hwsiii Questionnaire

[AguaSki]

1. 1978 Glastron SSV-188
2. Length 18?, Beam 88?, boat and motor together should weigh approximately 1,500 lbs.
2a. Don't know the recommended hp, but max hp is 150 hp
3. Two adults & two Children. Total weight is 171 + 126 + 61 + 53 = 411 lbs. Gas is normally 15-25 gallons
4. Water sports with the kids (tubing and skiing)
5. Think I have a deep-v. Not sure about the deadrise, but the sales brochure says transom width is 84.75?, and the depth is 45.75?
6. 1978 v4 Johnson outboard
7. 140 hp and 2.0 gear ratio
8. Manufacture recommends 4,500-5,500, but I see a lot people on this forum recommending 5,800 as a target.
9. About 1? above keel
10. No
11. Yes, Nauticas Smart Tabs installed. No hydrafoil or dolefin
12. Michigan Wheel, Apollo, 13.375 diameter, 15 pitch, SS
13. WOT is 5,300 RPM, 35 mph (GPS verified), 25 gallons, 411 lbs in passenger weight.
14. Normal operation is at 1,700 feet above sea level.
15. Three seasons of use with this prop. Nothing is wrong, just wanting to be sure I am maximizing performance as measured by RPM.
17. No
18. Want to try to get to 5,800 RPM without going down it pitch. It seems that others with a similar set-up get 5,800 RPM with a 19 or 21 pitch prop and I can?t get close with my 15 pitch. Should 5,800 be my target RPM?
19. Not really looking for better cruising speed and fuel savings, but out of curiosity I will eventually post these numbers.

 

[hwsiii]

Re: Completed The hwsiii Questionnaire

Ski, I show you should be able to do loser to 40 MPH with that setup and the only way I know to get loser to that speed and gain the RPM without doing a good amount of prop testing is to raise the motor another noth and that should raise the RPM and the speed some more. I also show you should be able to run a 17" pith prop, so you might hek the motor for timing advane and throttle advane is working right as well as spark and ompression. You ould hange props with less rake and more up possibly, but that might only gain a ouple of more MPH and raising the motor is definitely the least expensive without reduing the pith you are running right now. I have an Apollo myself and like it very muh, and your prop slip is only 7% so that is good. Maybe Dhadley will read this and make a reommendation, if he does you need to listen well.


H

 

[AguaSki]

Re: Completed The hwsiii Questionnaire

Thanks for the help. I raised the motor two notch's a few years ago. I have one more to go, but I am hesitant to go higher because the prop already blows out pretty good when I make the sharp turn to retrieve a fallen skier. When the skier goes down I like to get back to them as quickly as possible to protect them from the other boats on the lake, and I don't want to mess with prop blowout when I am in a hurry to protect the kids. I do most of my maintenance, but do have to admit I am not clear on timing. To compensate I take my boat into an OMC shop every other year for the stuff I don't do. Carb rebuild, linkage adjustment, and timing was completed this spring, but I don't notice any difference in performance. Most on this forum operate at near sea level elevations. Do you think my normal elevation of 1,700 feet is doing anything? I went to Lake Powell last week which is about 3,600 feet and noticed a drop in power. Maybe re-jet the carb?

 

[hwsiii]

Re: Completed The hwsiii Questionnaire

If you are already having blowout in orners now you are right. I just made a reommendation this morning for someone else to rejet their arb. Yes if you run at that altitude all the time. When the humidity goes up the higher you are the worse it gets.


H