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View Full Version : WTF - Used 28 Pitch prop I can put on a VP 280 T



scgj
08-26-2012, 05:56 PM
I'm toying with the idea of trying out a used 28 pitch prop to see if it a fit for my boat. I'm looking to get one "on the cheap" and if it shows promise, i'll pull the trigger on a nicer unit.

If anyone has a "beater" laying around that they could part with, please let me know.

Thanks!

- scott -

maddad
08-26-2012, 06:16 PM
Scott, I've never heard of any 28" props for an old Volvo drive. The biggest I've seen are a 26" Volvo ultra and a 23" Solas. What kind of boat and power do you have?

scgj
08-26-2012, 09:22 PM
The boat is a 19' Monza w/ ~425hp. I had read in an older thread that a prior owner had run one of these and was getting top end speeds substantially higher than what I am seeing....so I figured, why not give it a chance?

Thanks!

- scott -

Just Say N20
08-27-2012, 06:34 AM
A 28" pitch prop for the older Volvo 270/280/290 would be akin to finding the holy grail. With a 440 hp 408 going into a Ski-Sporter, I have been looking for something higher than the 26 Ultra for over a year without success.

If there is such a prop, it would be one of the best kept secrets out there!

Most of the old Volvos were set up with a left hand (counter-clockwise) rotation for the prop. Is this 28" prop left hand rotation? Is that what your 280 drive needs?

I have been to Michigan wheel, BBlades, etc., trying to find something higher than the 26 Ultra, and always get the same answer, "I can't help you out. There wasn't anything ever made for those other than the Ultra Volvo Penta props?

More info would be interesting.

mattyboy
08-27-2012, 07:46 AM
I have seen a 28 merc chopper prop exactly like the 25 I sent you Bill, it was beat up and really bad. the only thing I think will work would be to find someone who can press a michigan hub into a merc prop like the cleaver you have Bill.

I have also heard of but never seen a volvo with a merc shaft that would be another option.

mattyboy
08-27-2012, 10:33 AM
Sounds like you picked up bzmarine's red and white 19 monza

silverghost
08-27-2012, 11:03 AM
I remember seeing volvo aquamatic outdrive - to merc prop aftermarket conversion prop output shafts in a marine performance catalog sometime back.
I also remember reading on the web, possibly on this forum, that these would bend easily as the heat treatment for shaft's hardness was not done properly on these aftermarket conversion shafts.

Your best bet might be to get a new 23" pitch SS Solas Titan and take it to a good prop shop to attempt to bend-in a few more inches of prop pitch.
A prop shop once told me usually only about 2"-3" additional pitch can be cranked into a Stainless Steel prop without stress cracks developing.
It might be easier to bend-in a few more additional inches of pitch into an old Volvo 26" pitch Ultra prop.

scgj
08-27-2012, 07:41 PM
The VP 280 I have would be looking for a left rotation prop.

The boat I have is yellow and white w/ a red stripe :-)

I've got a relatively Solas Titan SS that is a 21p, maybe I should have a prop shop see what they could do with it? Anybody know of a good shop in the Minneapolis area?

Thank-you all for the feedback!

- scott -

mattyboy
08-27-2012, 07:59 PM
what are your numbers with solas 21??? it might be a better investment to get a 23 solas then try a tweak a 21 or try and find a 24-26 ultra. the solas run a tad more than the stated pitch the ones I ran were like 2 inches over the stamped number

Just Say N20
08-27-2012, 11:14 PM
you have not tried my 26 ultra yet..i bet you cant spin it past 5400..

Are you talking to me? :cool:

Hard to thoroughly test a prop, when the engine isn't running yet.

I don't know, at 5400 rpms I'm only down a few hp. On 87 octane 5,400 is still over 440 hp. Peak hp for my engine is 5,300. Max torque on 87 was 500 ft lbs. @ 4,300.

Now, whether or not I can DRIVE it past 5,400 is an entirely different matter. :biggrin.:

scgj
08-28-2012, 02:38 AM
Last time I was really pushing this I ran it up to 5k rpm and got 53 mph on an iphone GPS app (actually tried a couple of them to see if they would differ). The engine was pulling strong but I did not want to push it further. This was on a 15.25 x21p Solaris titan SS.

Not sure if/how this may factor into it, but I have never seen a prop throw so much "air" into the mix and it didn't seem to be effected by the trim...I'm kinda starting to wonder if my trim tabs are not coming all of the way out of the water?

As another possible clue, this never happened at higher speeds but with a few passengers running at ~ 25-30 (and not paying to much attention to trim), I have had a couple instances of prop blowout...essentially stalling the boat until the churn calmed and I could then again move forward.

Sorry if I am rambling on about things that may or maynot be relevant, but this is new to me and I want to learn as well as correct the situation :-)

Thanks!

- scott -

scgj
08-28-2012, 02:56 AM
Thanks for the DAH tip!

Just Say N20
08-28-2012, 06:50 AM
Last time I was really pushing this I ran it up to 5k rpm and got 53 mph on an iphone GPS app

Although I have never heard of it on a Solas prop, it sounds like the hub is slipping. The first engine I had built for my Sk-Sporter ran like it was about 260 hp. I could turn a Solas 19" to 5,000 rpms which was 53 on GPS.

The Solas prop doesn't react to trim like most props. They don't seem to lift the bow like you would expect. They were designed to run the boat flat. They also have very low slip numbers, like 3% or less. Here is a link to a prop calculator. Fill in all but one, and that one will be calculated. http://www.rbbi.com/folders/prop/propcalc.htm

53 mph @ 5,000 rpms sounds a little low for a Solas 21 Titan.

mattyboy
08-28-2012, 07:05 AM
That would be the first time I have heard of a solas cavitating or ventilating. the solas doesn't give alot of lift either bow or stern but all my testing is on a traditional Walters 24 degree rounded keel short inner strake. The monza hull is slightly different and from the one I have seen have more rocker in them, the ultra may be a better prop it carries more bow lift. those numbers are about right, how much do you think you had left?? jumping to a 28 from a 21 is a big jump that's a 1000 rpm or more might make it a bear to plane off, what does a monza 19 weigh??

Bill the numbers I have are more like 7-8 % and I had to add pitch to the stamped number to get any slip I had grip, if you run his numbers the solas looks like it is a 19.

maddad
08-28-2012, 08:52 AM
If you can spin a 23" Solas to 5000 rpm in an 18' classic, you will be just a hair under 70 mph. The math says that's -slip, but all my gps speeds/rpm data above 3000 rpm with the 23" Solas show -slip. I started a thread about it once, asking if others using the 23" were getting the same results, but the only person who replied was Randy saying yes, others were getting the same numbers. I don't think I've seen one post by anyone else who's actually running one.

Just Say N20
08-28-2012, 09:32 AM
I don't think I've seen one post by anyone else who's actually running one.

Perhaps soon. . . . . . . ;)

mattyboy
08-28-2012, 10:23 AM
The best I ever got on the 16 was 62.8 at around 4950-5000 rpm On 1.6 with an early solas 21
Run that thru the calc it has a canary need to enter 23 pitch in order for it to not have a canary

mattyboy
08-31-2012, 09:10 AM
Fix not bad for a lot more boat and a lot more motor.