mercuier alpha one gen 2 .. wrong ratio !!

[MikDee]

Re: mercuier alpha one gen 2 .. wrong ratio !!

that's why i said to go from the 19 he has to a 17....

Actually, if you do a direct conversion and assume that the new prop is as efficient as the old, an 18" with 1.84 is nearly equivelent to a 19" with 1.98...

Bondo- suggessted 15 before we learned that the tach was reading ca. 1/2....

Oops! Sorry, :redface: You're right Tim, that's what I get for not going back over the posts,,, (In my best Maxwell Smart), would you b-e-l-i-e-v-e,,, it's late, and I'm tired?

 

[Riggy]

Re: mercuier alpha one gen 2 .. wrong ratio !!

gauge is working know wot rpm 4400 ! I noticed once I started boat my rpm was about 1400 , so when I set the timing before I didnt set it at the correct rpm due to gauge set for a v8 . I adjusted the idle back to about 800 rpm and then moved the distributed by sound and driving it . I will bring timing light next outing to check it . I will have to say after adjusting the timing boat got on plane a lot faster seemed better .

 

[Riggy]

Re: mercuier alpha one gen 2 .. wrong ratio !!

Speedometer still isnt working ! no idea on speed .

 

[180shabah]

Re: mercuier alpha one gen 2 .. wrong ratio !!

idle still too high.

 

[Riggy]

Re: mercuier alpha one gen 2 .. wrong ratio !!

books say 650 to 700 idle . will adjust that and set timing again . my book also say timing 1 degree btdc . I cant say for sure since rpm gauge problem a butt motor seems better planing a little advanced . anyone advance theres with luck ?

 

[wca_tim]

Re: mercuier alpha one gen 2 .. wrong ratio !!

Oops! Sorry, :redface: You're right Tim, that's what I get for not going back over the posts,,, (In my best Maxwell Smart), would you b-e-l-i-e-v-e,,, it's late, and I'm tired?

Sorry if I sounded "short" was smiling and tired as well...

 

[Riggy]

Re: mercuier alpha one gen 2 .. wrong ratio !!

Update rpm gauge working fine . set my idle rpm at 650 and reset timing 1degree btdc . Tested it seemed ok . went back set timing at 6 degree btdc and idle rpm at 650 . Boat came on plane better . so thats where I am going to leave it for know . my wot was 4200 rpm . I have ordered trim tabs to help . when they come in . I will see my wot and give you all some results , along with the difference in getting on plane .

 

[MikDee]

Re: mercuier alpha one gen 2 .. wrong ratio !!

pretty much on the last post. in addition 1.98:1 vs 1.84:1 is like a couple of inches pitch. Did the same prop turn around 4600 or so before?

Higher number, more gear reduction, higher engine rpm per prop shaft rpm. I bet a 17" prop would hit right about where you want it to...

Seeing where you're rpm's are really at now, I agree with Tim, I recommend a 17" pitch prop to help your engine unwind to it's recommeded Max rpm, to take the load off at all rpm's, plus be more efficient, with a cleaner burn, to keep from excess carbon, & sludge, buildup! Good Luck, Mike

 

[Riggy]

Re: mercuier alpha one gen 2 .. wrong ratio !!

Ok , If I understand you all correctly a 14 1/4 by 17 pitch 4 blade would be a good prop due to my rpm ? also will another alluminum be ok ? or would the stainless be a better choice ? I didnt even think about my motor working harder with the 19 pitch ! Good info learning a lot from this site for sure . Thanks , James

 

[Riggy]

Re: mercuier alpha one gen 2 .. wrong ratio !!

all the 4 blades I see are 16,18 & 20 pitch ! and 15 inches not sure which one ?

 

[MikDee]

Re: mercuier alpha one gen 2 .. wrong ratio !!

Ok , If I understand you all correctly a 14 1/4 by 17 pitch 4 blade would be a good prop due to my rpm ? also will another alluminum be ok ? or would the stainless be a better choice ? I didnt even think about my motor working harder with the 19 pitch ! Good info learning a lot from this site for sure . Thanks , James

No, I meant a 17" 3 Blade! I don't know what you'd need in a 4 Blade, but I'd say less pitch then that considering that tall gear ratio

 

[Howard Sterndrive]

Re: mercuier alpha one gen 2 .. wrong ratio !!

I'm just doing a 4 to V6 conversion on an 18 footer here this week with a GenII.
I'm going to try a 23P once it's done. It has a 17P on it now.
If the 23 doesn't get it ballpark, I was going to buy a 1.84 upper. But if you can't get yours dialed in maybe we should trade outdrives

 

[Riggy]

Re: mercuier alpha one gen 2 .. wrong ratio !!

ok , Thanks mikdee I will look for a 3 blade 17 " ! Howard sterndrive Its a possibilty for sure . if we need to maybe we can work something out .

 

[Riggy]

Re: mercuier alpha one gen 2 .. wrong ratio !!

ok one last question . my wot rpm was 4200 that was checked with me and my son only ! normally we will have 4 or 5 people . another say 400 pds . my boat says rpm should be 4400 to 4800 . due to me only checking it with 2 of us in boat is the 17 pitch still ok ?

 

[180shabah]

Re: mercuier alpha one gen 2 .. wrong ratio !!

Adding weight will lower your rpm further.

For a WOT test to be valid, it must be done with a "normal" load. This includes people, fuel, fishing gear, coolers, toys etc. Anything that will usually be aboard.

 

[Riggy]

Re: mercuier alpha one gen 2 .. wrong ratio !!

OK , back to the drawing board ! will check again man the rpm will be low for sure .

 

[Riggy]

Re: mercuier alpha one gen 2 .. wrong ratio !!

I ended up getting another hustler alluminum prop 15 pitch . It works great the motor is much quieter and it planes and pulls a skier up much better . Also the trim tabs work great as well lower planing speeds and the boat turns a lot easier know . Thanks everyone for you input and ideas it has made my boating more enjoyable ...Thank You All .