Prop suggestions wanted

[Supernova]

Hi all. I have a 1984 Diplomat with a 1993 Mariner 150 v-6 on it. It had a 14.25x21 aluminum hustler on it that the P/O trashed. I happened to have a 21 pitch 4-blade Trophy in my treasure trove that does fit on the motor properly. What do you think? Any suggestions would be greatly appreciated. Thanks in advance.
--
Stan

 

[Mark]

The Trophy sounds like a perfect choice. Have you tried it? Got numbers? I would add a small setback jackplate, 3-4" and raise the motor as well. Too much setback with a V6 will cause it to porpoise at lower speeds.

 

[Supernova]

The Trophy sounds like a perfect choice. Have you tried it? Got numbers? I would add a small setback jackplate, 3-4" and raise the motor as well. Too much setback with a V6 will cause it to porpoise at lower speeds.

Haven't tried it yet--will this weekend. I was thinking about a jackplate as well, but I wasn't sure how much setback I would need. Any recommendations on a good make and model for the jackplate? There was a hydrofin on the lower unit and I took it off b/c I never liked them very much. Do you think that was a mistake?

 

[jallen355]

I agree, the Trophy will be real close. If not, however, I would be interested in taking it off your hands. I've been looking for one myself. Good luck and let us know how it works out for you.

 

[Mark]

I run a fin on mine but I cut it down (width) so it wouldn't drag when on plane. These short hulls go nose up on holeshot. I have a 6" Slidemaster JP on mine with a 130 Yamaha. It is a touch more than I would like but livable. The V6 will weigh more, that is why I think you only need 3-4" Any make is fine as long as it is a one piece unit. The Trophy will run even better once you get some engine height.

 

[Supernova]

I agree, the Trophy will be real close. If not, however, I would be interested in taking it off your hands. I've been looking for one myself. Good luck and let us know how it works out for you.

Thanks. I'll keep you in mind if it is no good. I had this prop on a 19' Wellcraft that I put a high-performance 355 in and it kicked ass. It over-revved a little, but there was NO holeshot to speak of, it just lept right up on plane as soon as you nailed it. If I didn't mention it, the prop is ventilated.

 

[daren34]

Hi all. I have a 1984 Diplomat with a 1993 Mariner 150 v-6 on it. It had a 14.25x21 aluminum hustler on it that the P/O trashed. I happened to have a 21 pitch 4-blade Trophy in my treasure trove that does fit on the motor properly. What do you think? Any suggestions would be greatly appreciated. Thanks in advance.
--
Stan

different props take different spacers
there are 3 different ones that i know of

go by a merc shop with the prop and boat and see if they can get you the right one

if you don't run a spacer the prop will hit the carrier nut

daren

 

[Supernova]

The Trophy sounds like a perfect choice. Have you tried it? Got numbers? I would add a small setback jackplate, 3-4" and raise the motor as well. Too much setback with a V6 will cause it to porpoise at lower speeds.

Well, I ran it on sunday on the local lake up here, and all I have to say is H.S!!!! We hit 74.3 mph on gps at about 5200 rpm, the boat was still accelerating and we hadn't trimmed all the way up yet, but she was getting loose and it was a bit rough out (1-2' waves, easy) so I backed her down. My 7 yr old and 4 yr old loved every second of it. Their faces are all wind-burned. The motor feels like it is missing between 1100 and 2200 rpm, but it idles fine and takes the throttle fine, although when I am running steady at say 3100 rpm, it feels like it is surging about 100 rpm and it shows on the tach.
--
Stan

 

[83PREDICTOR]

74+ in a Dipper is very good.

You sure you dont have a 200 under that 150 cowling? lol

 

[jallen355]

Sounds like you have a prop!!! That's screamin's for a 150... I found myself a 21 Trophy Plus over the wekend and should have it strapped on for the coming weekend.

 

[Supernova]

74+ in a Dipper is very good.

You sure you dont have a 200 under that 150 cowling? lol

What you mean is 74+ in a Dipper is insane--the hull wasn't built for it, I don't think. It doesn't handle it very well. Maybe a set of trim tabs to give the hull a little more length and stabilize it a little? I know they work wonders on my Wellcraft.

Oh, by the way, It's a 135 cowling. The boat is only rated for a 140.

Is it possible to work these motors? Maybe someone did something to it already?

Jallen355--do you mean the rpms are sreamin--or the speed is screamin?

 

[Mark]

I don't want to be a wet blanket here, but 74 MPH is physically impossible. A 21" Trophy turning 5200 RPM with a 1.87 ratio gear case will give you 55 MPH with zero slip. Something is giving a wrong reading. My guess would be the GPS is off because you would need to be turning 7200 RPM with that prop to see those speeds. Nevertheless, I'm glad the prop ran well for you. The Diplomat hull starts to chine walk at about 55 MPH and gets to be quite a handful at 60.

 

[jallen355]

Thanks Mark. I've been bummed all day wondering why I can only manage 60 w/my "slow boat"...lol!

 

[zstevens]

if your looking to dump the trophy i'd like to put my name on it ! ! ive got a 21p laserll to tempt you w , jallen 355 , whered you find/buy it? hows it workn out ? im gonna have to demo one

 

[zstevens]

i want a trophy too !

 

[jallen355]

if your looking to dump the trophy i'd like to put my name on it ! ! ive got a 21p laserll to tempt you w , jallen 355 , whered you find/buy it? hows it workn out ? im gonna have to demo one

My 18' Exciter did not like the LaserII 21" I ran. Turned 5900 rpm/60 mph. Pretty good luanch and equalled my top speed (slow) to date, but it did not like my engine height (4" below) which I consider low, but I don't have a LWP. It would also bust loose every time I slightly turned the wheel one way or another at higher rpms.

I picked up a 21" Trophy from a S&F member who bought it last week from yet another S&F member. He found he needed more pitch so I scooped it. Who knows, maybe I'll post it up for sale here next week.

 

[zstevens]

i dont have a lwp ,hell i dont have my water psi gauge mounted yet ! but it seems the trophy is in most cases a best of both prop topspeed n holeshot ! from my readings

 

[jallen355]

What kind of numbers did you get w/the 21" Laser II??

 

[Supernova]

I don't want to be a wet blanket here, but 74 MPH is physically impossible. A 21" Trophy turning 5200 RPM with a 1.87 ratio gear case will give you 55 MPH with zero slip. Something is giving a wrong reading. My guess would be the GPS is off because you would need to be turning 7200 RPM with that prop to see those speeds. Nevertheless, I'm glad the prop ran well for you. The Diplomat hull starts to chine walk at about 55 MPH and gets to be quite a handful at 60.

That is exactly what I thought, Mark. There is no way a 21" can hit that speed at that rpm. I'm thinking the tach has to be off, although I have to admit that the last rpm reading I took was at 5200 and as I said before, the boat was still accelerating. The problem was it was getting to be quite a handful and I had to keep an eye on the water, not the tach. My brother was reading the GPS, so I have to trust what he was telling me.

Also, I bought the prop off a guy who used to run it as a matched set on a CC with twins. He told me it had been worked, but not exactly what was done to it. It may have been re-pitched, but I am just guessing here.

Last question; how possible is it that the speedo is screwed up. It was a handheld Magellin GPS. I thought GPS speed was the end all, be all for speed readings. Are they fallible?

I would love to figure this out. I am going to call my bro and see if he was exaggerating the speed just a little.
--
Stan

 

[83PREDICTOR]

If you think it is your tach. next time you are out wiggle the pulse setting on the back of the gauge a few times and see if reads.

Sometimes my new gauge is off by 2000 rpms then I just touch the pulse setting then it works again.