wot question

[ob]

Re: wot question

I recommend the 13X19 and if you can get one in stainless thats double cupped..... even better.Your engine will live longer and run cooler being capable of the 5900 rpm instead of the extra load that the 12 3/4 X 21 is putting on it.Was the 13 X 19 you tried out an aluminum?If so the SST should perform even better.That's my opinion.

 

[peeterb]

Re: wot question

Sorry I forgot to put that in m y last post Yes the 13By 19 was a aluminum.Is it okay if the engine hits 5900 r when coming out of yhe hole for a short burst and then take the r down to 5400 rpm.<br />Thanks

 

[rickdb1boat]

Re: wot question

glassc<br /><br />Yes, that is fine on the RPM's coming out of the hole..

 

[Dhadley]

Re: wot question

You can run the motor at 6100 all day with no damage. The stock steel reeds start to give up on that motor in the 6300 to 6500 range. The stock intake manifold gives up at about 6900 to 7000. <br /><br />I agree that with your current set up the 19 is the way to go. 5900 rpm is perfect and speed is very good too. I might be tempted to try raising the motor with the 21 to get more rpm (and therefore more speed). 5300 is killing the motor.

 

[peeterb]

Re: wot question

Thanks you guys, another question answered because of your help.<br />19" pitch will be on my boat today.I was very happy with this prop also.

 

[peeterb]

Re: wot question

Been at the lake for two whole weeks and boat never left the water.lots of time to try props.<br />13x19 aluiminum worked very well.I purchused a Hustler prop 13 1/4 x 19 prop and tried this thinking it would be perfect but even trimmed right up I could only get 5200rpm at wot and 44 mph.My question is why does this hustler prop make such a difference on my rpms?Does the little difference in diameter and cups change the rpms that much?<br />Thanks

 

[jack7771]

Re: wot question

Originally posted by glassc:<br /> Been at the lake for two whole weeks and boat never left the water.lots of time to try props.<br />13x19 aluiminum worked very well.I purchused a Hustler prop 13 1/4 x 19 prop and tried this thinking it would be perfect but even trimmed right up I could only get 5200rpm at wot and 44 mph.My question is why does this hustler prop make such a difference on my rpms?Does the little difference in diameter and cups change the rpms that much?<br />Thanks

glassc,<br />Did you ever get an answer to this? I was doing a search because I also have a 110 Evinrude and a 16' fiberglass boat, and I was wondering what is the max/min RPM for the motor at wot.<br />Also, I recently ordered the new hustler prop (2005) -- actually one 17" and one 19".

 

[Dhadley]

Re: wot question

The V4 crossflows live the longest when set up for a minimum of 5800 with an average load. 5200 as a top rpm will cause stress on the motor and may lead to a premature failure.

 

[jack7771]

Re: wot question

Thanks for that input. I guess (from your previous comments) that 6100 rpm is the "safe" max for this 1986 motor. I hope the Hustler props I ordered don't bring the rpm down to 5200.

 

[jack7771]

Re: wot question

I fairly recently purchased the 1986 boat & motor and the prop that came with it is 17" and only gets 5450 rpm, but it is a little dinged up and that's why I ordered the new props. Is there much chance the tach could be wrong?

 

[reeldutch]

Re: wot question

thicknes of the blades and rake might have to do with it.<br />every prop even if it has the same diameter and pitch are not the same.<br />your hustler could be cupped.<br />but i'm not a expert on this.<br /><br />good luck

 

[jack7771]

Re: wot question

Well I got a manual on my motor (1986 110 hp Evinrude), and it says Full Throttle Operating Range = 4500 to 5500 RPM<br /><br />So, I wonder where Dhadley gets "The V4 crossflows live the longest when set up for a minimum of 5800 with an average load"??

 

[wilde1j]

Re: wot question

Trust DHadley!!! Forget the book ... DHadley (and a few others) know what they are talking about and have many years of experience. Almost all of the OMC v4 and V6's should be propped to run ~ 5800 @ WOT. If you don't, expect lots of carbon buildup, etc, etc.

 

[jack7771]

Re: wot question

I am all for experience, and I assume OMC had plenty of it when they put 4500 to 5500 RPM in their manual.<br /><br />So it does make me wonder what is the validation for stating "a minimum of 5800 with an average load" and "You can run the motor at 6100 all day with no damage" -- don't mean to be contentious, but 6100 rpm is significantly different than 5500 rpm!

 

[wilde1j]

Re: wot question

Jack777, have you ever rebuilt one of these crossflows? I have and so has DHadley (many times), so we know the results from poor setup practices.<br /><br />Also, if you have an issue with your boat, start a new thread, don't hijack this one please.

 

[jack7771]

Re: wot question

Jim,<br /><br />I don't mean to be contentious -- I appreciate the advice and time spent by others to answer so many questions. Let me just say I have worked with some big outfits (names unmentioned to protect the innocent) whose "experience" has led to some totally erroneous conclusions/directions.<br /><br />So, I don't want to offend anyone, especially not DHadley who I see has been a big help to many. I was just naturally wary (coming from an R&D background) why a major, long-lived, corporation like OMC would not have the best insight on the matter after producing thousands upon thousands of motors (notwithstanding above comment on big outfits). <br /><br />I wouldn't have even asked the question if I'd bought the book first. But now seeing there is a conflict between OMC and what I sense is great experience by DHadley, I've got to wonder "why?" and is there any recorded validation which over-rides what OMC says. I actually wanted to email DHadley instead of posting here, but apparently I'm too dumb to figure out how to email someone on the forum <br /><br />BTW, I bought the boat and motor at the "last minute" after discovering the place from which we normally rented a ski boat was out of business. We had a big family water-ski outing planned, and I wound up quickly buying the boat to "fix the problem" -- it was just one of those crazy situations. And now I'm a hooked boat owner again after 30 years of rental!