Harley 42'

Prop Udate: didnt go well. I mounted the 4 blade clevered 17.25x23 pitch blades on and my 502s could not get on plane at all. We tried a few times but not even close I am wonderring if the 23-pitch is accurate. Might get them looked at/scanned to see what gives. They shoud have worked....not ever close.

I am busilding some ventilation snorkels for the boat...probably re-install the antique props for now....mount the snorkles when they are ready and then try these clevers again. Very dissappointing indeed!

 

Hey Oliver!

Sorry to hear about your prop testing. How did you get them to fit?

Rule of thumb says you will loose about 200 rpm for each one inch increase in pitch. Then another 200 rpm loss from the extra blade. The lower that figure some for the smaller diameter.

19 to 23 pitch = 800 rpm loss?
3 to 4 blade = 200 rpm loss?
19" dia to 17.25= 200 rpm gain ?

The sum of above numbers is an approx loss of 800 rpm. This would lower your WOT from 3600 to 2800 rpm.

I went from a 18X21 three blade nibral to a 17.75"X22 four blade I lost 400 rpm. Sent to BBlades to get my rpm back up. He reduced diameter to 17". added cup to blade tips to get the bow lift back and reduced blade area some. Now my rpms are in the ball park but they are not as near as efficient as they were. They work OK at 38 mph or faster, but not very good at lower speeds. Oh well lesson learned. I am waiting to hear back from ellis
propellers on a set of nibral 4 blades. We'll see

Steve

 

had a freind machine them a little - took 1/32 out of the hole for me...19-splin end always did fit right. Then he made a spacer for the prop side.

it felt like the HP wasnt there to make it go - I am going to try snorkles once I get them done to see if it helps the motors spin up....I suspect I will have to get them tweaked alot or BLOWERS baby ;-)

 

I have a two week vacation planned in the abacos this summer and this pig better run well by then. I might get some cup taken out of my old 3-blade props to gain some rpms and use the snorkels to help it get on plane with less load.

Then when I get back from the bahamas - I think I want to add some baby blowers with 3-4 pounds of boost. This should give me about 525 hp per motor but more importantly - more torque accross the powerband. IT'll suck gas more but I should be able to curise at better speeds with lower rpms....yes new props will be required.

The only alternative is to get 2:1 transmissions, change props, and stick with what I got for HP. If I find some straight BW72Cs with 2:1 that can be reversed as needed...then I will probably buy a pair of crate 540s (or long blocks) that both spin in same direction and repower next winter.

PS- my wife has almost had it with this project ;-)

 

Well I just ordered a set of props from John Rose @ Ellis Propellers. He recomended 17X20.5 4 blade, round ear, and relatively large blade area. I thought 17 sounded a little low on diameter. But John assured me that it would work just fine. He seemed very familiar with Harleys. Price is pretty fair at 975 ea. Fair as long as they work! Main goal is smooth and quiet operation, and equal or better performance. John said he thinks that I will end up with a higher cruise speed. That sounds awsome if it happens. I won't get them for about three weeks. So I am cautiously optimistic at this point.

Hey Martin: are you still around? Have you done any testing with your new props? If so lets here it

Oliver: I still think you should try the props I sent you, they are still in the box if you want to try again.

Steve H

 

Steve, I would have to have them bored out to fit my shafts - I dont want to do that to them bro.

 

46 Harley

Greetings-
Yes still here. I am almost done with my forum, I want to transfer the Harley conversations to the new site if you want. In the meantime can you guys email me the following;

name
email
contact#
boat size, type
engines
trans
props
speeds
comments

I will keep this completely confidential and you will be asked pemission before it is released on a case by case basis (another Halrey owners wants to talk to you).

I wil post boat info up on the site for others to use as a reference. I have a lot of this info but i would like to confirm and complete. Since I started this I have had several owners come out which are not part of this site.

my email address is; martin@coastaloffshore.com
(361) 949-2628 or if you have the padredevelopmet address it still works. The web site is www.harleypowerboats.com

Martin

 

46 Harley

Steve:
I have been having my own prop difficulties. I bought a new set, 25x35x4. They are not letting me turn the RPM's i need. I am 400 short of max. horsepower. I have made several corrections and I am completely frustrated. They are now 25x33.25x4. I borrowed a set from a friend who had 22x30x6 and they ran the best and smoothest although they were too small. Here's several recent items i learned;

In order for the boat to perform max. it will not come up w/o cavitation tubes. I attached picture before and ill do it again here. If it does, then you are losing on top end. All boats using ASD's (new) have these tubes. The best props I have seen on these(our Harleys) boats are 6 blade round ear. They cost about $6000USD for a pair. I am tempted to order another set like this. More diameter the better you are in the "surface mode". I can not see how a 17" diameter will work but I have also never heard of a new prop in this style costing under a $1000. I learn stuff everyday.

Currenty I am seeing 38knots w/o all the rpms. I do not know my next step and fishing season is here so I may live with it for now. Most of the Harley owners see more thn 40knots when set up. I am burning 14/16 gph per side, or 1.2/1.6 mpg.

I am also going to add some weight back to my bow as I think i took off too much during the refurbishment. It is little light in the front.

I am going to go back and read through the old post and make another comment if I see something relevant. Steve, what props do you have?

Martin

 

46 Harley

Guys:
With respect to the cavitation tubes-I took mine off becuase I did not need them with the old props. My new props would not even turn to a plane. I put the tubes back on and it popped right up. I would personally not attempt props without tubes. They are critical in the equation. I took a tour of the Fountain Factory last year and of the boat models they were running with twin and triple ASD's , they all had these tubes.

As for the lift, Bert Kehren had his 42' on a lift in Miami. Ill attach a picture. I have plans to put mine on a lift. I orginally bought a cradle base from Harley because he said that it needed it for support. I paid him $2000. I still have it. Its a perfect form of the bottom of the hull and was used in the shop when boats came in without trailers.

Finally, on value. There have been 2 42's for sale for several months if not longer, one for 135k and the other for 175k.
I have seen a few move under the 100k price, in the 70's.
It is totally subjective to the condition, power, ect.

Ok, thats my 2 cents. Ill let you know what happens with my props.

Martin

 

A freind is making me a set of ventilation snorkels - when I get them back - if they work well - I will see how much he would chanrge to make a bunch of them.....keep you posted.

 

46 Harley

Swamplizard:
If you look at the pictures I attached you can see the two different styles. On my boat I used stainless and then rubber hoses to each end, sucks right up the prop and comes out under the platform. My tubes are ventilated by the exhaust. Bert's has brackets on the drives and then a hose ran up through the platform. I had that previously but it did not last, therefore, the beefed up version. The type Bert has are obviously much easier. Make sure they are close to the props and the top of the tube has a way to get air, or exhaust. Its hard to belive but those tubes will slip the props immedialtey.
Stay at it and Ill do the same. If you want any additional pictures sent directly to you, I have several.

Regards,

Martin

 

Currently 18 X 21 3B Old style Rollas. Howard Harley called then elepant ear props, Rik @ Arneson calls them chopper props. Their performance is fine. I just need a smoother and quieter prop!

Steve

 

I sold my 4-blade cleavered props since they would not work for me and I am back on the hunt for some I can use as spares (at the very least) in case I hit a damn reef in the bahamas and need to limp home. For now - I'll be using my 3-blade elephants though I liked the smoothness of the 4-blades :-(

My snorkles go on this weekend....I'll post results but they will be with the old blades.

If I can't find any better ones or if the CFO wont approve the blower project then I guess I might do like Steve and buy a pair of new 4-blade bonze round eared props. Look forward to hearing Steve's results. Cheers all and good Memorial weekend - get out and burn some fuel!!!!

 

46 Harley

I currently have three sets of props. I do not know if you have an interest, they are 25 tooth spline so you would have to have 19 tooth spline. They are 3 blade, 24x26-they came off a 42 Harley. Let me know, thanks.

Martin

 

I have four sets: I win

Steve