Columbian L6 JB three blade bronze cleaver

[paavojaelvis]

Hi, folks!
I recently acquired an old Columbian cleaver "L6 JB". Diameter is 10 1/2" and pitch looks to be around 14"-15". Hub is cushioned, 20 mm smooth bore with shear pin. Fits to some 60's OMC? Hub has spun, so I'm going to fit a 14-spline Chrysler hub and run it in my '71 Chrysler 55 hp/15ft monohull racer from the same era. I would be very happy if somebody could tell me more about this propeller. 6230062301

[filthy phill]

dont knowanything about these, but looks a nice prop in pretty good shape.
hope your going to give it a nice polish up ? it deserves to shine .

must be plenty of folks out there who know these props, I am in England uk and have heard of them but never seen one.

I bet ron hill knows about these, or one of his buddies.

[paavojaelvis]

Measured it, pitch is 13" average. Anyway, I'll give it a try...

[filthy phill]

well worth trying it, and if its not enough pitch being bronze could be worked on easy to take it up a couple of inches by a prop shop.
plus a few other mods and make it a great prop for you motor.
plus dead easy to keep it polished and look real nice ha ha .

[paavojaelvis]

Cleaned it a bit with 320 grit paper. Next job is to make a press fit sleeve for the hub and put it all together. Truing and a test drive after that. Wish me luck... ;)62337

[hupiveneilija]

Cleaned it a bit with 320 grit paper. Next job is to make a press fit sleeve for the hub and put it all together. Truing and a test drive after that. Wish me luck... ;)62337

What splines? I do have tools for changing omc 13spline rubber hub.
Coming to MSSA?

[paavojaelvis]

What splines? I do have tools for changing omc 13spline rubber hub.
Coming to MSSA?

That's Chrysler 14 spline hub, going to make it solid. Yes, MSSA is in my plans, hope I will make it to Puumala this year. If I'm lucky, maybe even back to Lappeenranta... =D

[filthy phill]

once you get it done, remember to balance it !!!! and a polish up once its done would make it look that bit better.
also a highly polished prop helps you see if any cracks start to appear.

Balancing the prop will make it run a lot better and save the life of the hub and your gears too.
be surprised just how out of balance a prop gets, especially as when new most are way out of balance.

if you dont have a balance they are easy to make.

here is what I made recently and works a treat for any prop upto about 16 inch diameter. the cost of this was zero as everything made from old scrap bits lying around.
you can buy a motorcycle balance that works just like this does, but making your own is better for the wallet.

.

[Fastjeff57]

Love that rig! Plan to build one myself.

Thanks.

Jeff

[filthy phill]

simple to make, and when balanced the props do run a bit better.
got to be easier on the shaft bearing life too ?

[Fastjeff57]

..."simple to make"

You weren't kidding! Took me only an hour or so, and it works slick!

Thanks,

Jeff

[filthy phill]

Now you can get all your props to be that little bit better.
you will also see how some are so far out of balance its incredible.
got to be much easier on the prop bearings for longevity.

[Fastjeff57]

You bet. Tried to upload a photo of my rig but the site was being muleish.

Jeff

[filthy phill]

pm me your email and ill upload the pics for you.
the site has changed a bit.

but when trying to upload on here in the box look for basic uploader, then try from there.
if no luck send to me and ill post them for ya.

[paavojaelvis]

First test run, propeller fully submerged... 38,5 mph@4800 rpm. Not bad at all. :)

[filthy phill]

where did you get the gear ratio from ? and what did you use for a speedo ?

[paavojaelvis]

Gears are 21:13 and speed was from GPS.

[filthy phill]

Have you double checked on the gear ratio by turning the motor over ? I had a old 55 that was 2 to 1 ratio.
think mine was about 1974/75 could be a bit wrong on the year but 100% it was 2 to 1 ratio.
I know the old Chrysler was only meant to have about 13 pitch prop, but if yours is pulling it then great, but it needs to reach max revs.
you might be able to tweak it to what is best, faster out the corners too if a touch less pitch.

but to just get an old prop and get that speed from it is fantastic. plus it looks a very cool old school prop too.
nice that you managed to re-hub it too, makes it a very good usable item.... and rare ha ah

[paavojaelvis]

I have had those gears in my hands numerous times, so no need to re-check... ;) Anyway, i'm already happy with the prop, and i'm sure it will build more speed when jacked up a couple of inches. We'll see...

[filthy phill]

I think its a nice piece of work, something about a nice bronze prop, I do like my shiny stainless, but bronze just has that typical nautical bit extra.

[paavojaelvis]

Jacked up 2" -> 40,5 mph@5000 rpm. Porpoising, must try again with full tank & co-driver on board.

[filthy phill]

thats a good speed from that motor and prop.
do you have a set back/ jack plate or just raised engine on transom ?

[paavojaelvis]

Jack plate with 4" setback.

[filthy phill]

if you want to try a little bit more setback.
place a 1 inch piece of ply between boat and jack plate to give you 5 inches setback, and another piece of ply between engine and plate for 6 inches of setback.
might improve the porpoise ? plus give more speed.

it is doing pretty good already though.

[paavojaelvis]

Prop shaft 2" below hull bottom, worked well in choppy water.
https://www.youtube.com/watch?v=UI3tgFVkeGs
https://www.youtube.com/watch?v=YqVFS4vfUv0

[filthy phill]

Yes it's looking good.
Maybe need to trim engine out about 3 inches at the prop to get motor more level, but that prop is definitely getting boat going well.
love it when an old forgotten prop turns out to be just as good (if not better) than new ones.
Looks like you had a good ride and plenty of fun.

[paavojaelvis]

Thanks Phil, I'm very happy with that set up, it was trimmed a couple of degrees negative due to choppy water. It was easy to cruise @34-35 kn with no whoopsies, topped out @37 kn. I'll try it an inch higher at my home lake, I believe she'll gain a couple of knots easily. As you can see from vids, there was no spray from prop at all (still submerged). =)

[filthy phill]

You will never get any spray from prop because it is trimmed in far too much. You will gain 3mph just by levelling engine out. Then see about raising it if you want. But definitely going very well at the moment even tucked under. .

[paavojaelvis]

Don't let pics and videos fool you, gunwales and hull bottom are not parallel. Trim setting is +1 to -3 degrees depending on conditions. I don't have hydraulic trim/tilt so it's not possible to trim out while driving. And more positive trim during takeoff means no planing. Have I tried? Yes. There has been three different sets of wedges at the transom to get the angle right. With hydraulic trim, that'll be an other story...

[filthy phill]

That engine is tucked under by about 10 degree. As for take off, distribute the weight better. There is no way the motor is anywhere near level or would see prop wash ( not rooster). It's the reason boats used to have ballast tanks up front (some still have them).
I go by the motor compared to water. Not the boat. Boats don't ride level on plane the majority of the time.

[paavojaelvis]

Phil, you are right with weight distribution. But it's not the way you think. There should be more weight in the rear end. Problem with take off is, this boat lifts its rear end too soon, propeller looses grip and boat comes into halt, well almost... :p This hull was designed for dual engine set up (two 500cc Crescent outboards). With Chrysler, i have 65 kilograms less weight at transom. Not to mention my co-driver (7 yrs/28 kg)... ;)

See magazine article about my boat under construction ("Vauhdin Maailma", July 1972). Unfortunately it's in finnish language, but you can enjoy the pics. 62468

[filthy phill]

You need a bow lifting prop. I have problem with bow on mine, once I hit about 36mph the back just keeps lifting.
I Can't put any more weight at back or it would sink at standstill.
But your getting there with that boat, just need to get prop tweaked to give bow lift. Soon be way over 40mph with that.

[Fastjeff57]

Maybe I'm all wet on this (hah!) but I've always believed there is no such thing as a 'bow lifting' prop. Props are either stern lifting or neutral,

Ron?

Jeff

[filthy phill]

Ahh this is where things get complicated.

A true neutral prop would have zero rake, then it would neither put the bow up ( obviously a slight bit due to forward motion. ) or back up.
Lots of props out there with neutral lift, but mainly on slow or heavy river boats, these give better revers thrust .

I think its one of those chicken v the egg type of things as it depends how you want to look at it.

[zul8tr]

Maybe I'm all wet on this (hah!) but I've always believed there is no such thing as a 'bow lifting' prop. Props are either stern lifting or neutral,

Ron?

Jeff

Right on the lifting and neutral but also there is rear dropping case. With rake the direction of changing forces on the blades is very complected depending on submerged or surface piercing prop as they rotate. Rake tilting rearward is + rake and generally more rake drops the stern, the result is the bow goes up, props that lift the stern have low or zero rake. Ex my 3 point hydro props have small 6 degree rake and lift the rear. Lots of rake not needed because there is compressed air under the hull for positive bottom air pressure aero lift up + hydrodynamic water lift up from the the rear plane surface wedge thru the water + aero lift up on the deck to raise the bow. Consideration of the location of the center of gravity needed and all these lifts create induced drag. Hulls with little ability to cram air underneath and not that much deck aero lift (deep Vee jobs etc) need lots of + rake and engine trim out to get the bow up which isn't always the optimum direction for forward thrust force. It is a compromise on these type hulls due to reduced or lack of air lift forces noted for 3 point hydros.

Mccauley on rake:

http://mccauleyandson.com/html/props.html#rake

[paavojaelvis]

I modified this prop by adding about 1/2" more rake. Income: comes out of the hole better, even trimmed out (3rd hole). Gained a bit speed, too, now we are above 38 knots (driver only). Still porpoising in calm water, got to check the hull bottom before any more modding.

[paavojaelvis]

Had fun with friends in Saturday. Here is some onboard footage, the fun part starts at 5.40... https://www.youtube.com/watch?v=JDFPGljIgY8&t=14s

[Fastjeff57]

How did you add more rake? Weld on the blades?

Curious.

Jeff (home made props maker)

[filthy phill]

Looks like the motor is running very good for you.
that porpoising will never go unless you trim it out a touch more, motor is not running level enough causing the front to keep dropping.
you will get another 2 to 3 mph atleast by trimming it out a bit more.

you had a good bit of fun with it though, I need to get mine out this week if weather holds up.

and what happened at the end of video ? run out of gas

you cannot add more rake to the prop without taking the blades off cutting to different shape then welding back on (very dangerous), you can put cup in the tips to
act like a touch of extra rake, but rake is the blade angle to the hub.
Maybe you mean added pitch.

[hupiveneilija]

Had fun with friends in Saturday.
Yes we did!:cool:
It was quite a BANG!

[paavojaelvis]

How did you add more rake? Weld on the blades?

Curious.

Jeff (home made props maker)
Well... I gradually added pitch along outer half of the blade. This is not a typical racing cleaver, its more like a "Mickey Mouse" fishing motor bronze prop from the 60's but with straight, cupped trailing edges. Blade profile is "twisted" in such a way that pitch was decreasing towards trailing edge and towards the tips. I'll take some photos to make it more clear.

Phill, pinion bearing disintegraded and broke the casing at the end of the video. I think that gears and prop shaft are still salvageable.

[filthy phill]

That is bad news.
I am not sure you will find a spare case for that easy nowdays. Maybe a later gearbox is going to be needed to join up.
Chrysler were very weak on the drive train. Maybe this engine was not looked after 100% before you got it.
Hope you get it sorted out because you were enjoying the boat.

[paavojaelvis]

That is bad news.
I am not sure you will find a spare case for that easy nowdays. Maybe a later gearbox is going to be needed to join up.
Chrysler were very weak on the drive train. Maybe this engine was not looked after 100% before you got it.
Hope you get it sorted out because you were enjoying the boat.

No problem, I still have 2 or 3 lower units as spare parts. I'm pretty sure that oil seal under water pump failed -> water in/oil out -> bang! Yes, I have water pick up tube at the transom and there is only one seal under the pump... :rolleyes:

[filthy phill]

oh that is good you have spare parts for the motor.
it runs realy nice.
years ago when Chrysler were selling outboards in the uk the only problem they realy had was breaking main drive shafts, parts were never easy to get even back in the 1970's in the uk.

your motor sounds nice, hope you get back on the water very soon...

[paavojaelvis]

Well... I gradually added pitch along outer half of the blade. This is not a typical racing cleaver, its more like a "Mickey Mouse" fishing motor bronze prop from the 60's but with straight, cupped trailing edges. Blade profile is "twisted" in such a way that pitch was decreasing towards trailing edge and towards the tips. I'll take some photos to make it more clear.

Here are some pics. Rake angle was zero before mod.

[Fastjeff57]

You do nice work! What type of welding did you use?

Jeff

[paavojaelvis]

No welding, needed only a small hammer and lots of patience... ;)

[filthy phill]

Looks like you have put it back to what it would of originaly been like.
the rake is the same, rake angle is determined at the hub, look at the last picture the tip of the trailing edge should infact be up a touch more to be like what it would of when new.

being a manganese bronze prop ( brass), the prop has probably be bent many times in its life. Unlike alloy props the brass gives a bit more without cracking.
I bet that prop could have some real history to it.

its definitely in good hands now, time to get polishing and make it look like new, its definitely a keep prop for sure.

good work done by you too to get it back to looking right.