500? Caddy

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seaurchin1969
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Re: 500? Caddy

Post by seaurchin1969 » Thu Apr 16, 2015 1:54 am

http://pages.ebay.com/link/?nav=item.vi ... 1299864168
Here's that caddy motor on eBay its $595.00
16 X 72" Combee hull 500? Caddy dd

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Re: 500? Caddy

Post by One Eyed Gator » Thu Apr 16, 2015 9:37 am

I got a caddy motor for you.

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Deano
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Re: 500? Caddy

Post by Deano » Thu Apr 16, 2015 3:25 pm

seaurchin1969 wrote: . . . the engine casting# looks like 49500, and from reading posts, that makes it a 472/500, and I'll have to drop the pan and look at the crank to confirm cid. . . . Beyond that I have had no real problems, just not the power I would expect . . .
No need to do that, just pull a plug and stick a pencil, straw, or something in the cylinder and measure the stroke. A 472 will be a hair over 4-1/16" and a 500 will be a hair over 4-1/4". Anyway, that's an easier way to determine what it is or isn't.

seaurchin1969 wrote: . . . Maybe I can track down some smaller cc heads hmmmm :twisted:
Be forewarned before you go learning the hard way; doing that will require the correct (different) pistons that match the heads. You can not simply go slap some small chamber heads on a later model long block.

IMO, the minimal difference it will make at the 3k rpm limit imposed by being direct drive, does not justify the additional expense or the associated requirement to run 93 octane. Maybe those differences could be justified on a light 12' sled, but definitely not on a 16' hull rigged for bow fishing.

Evidently, OEG still has the engine he had for sale, that would be the ticket. You could just install that with no worries and then redo the one you are currently running at your convenience, if you wanted a second one. :thumbleft:
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seaurchin1969
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Re: 500? Caddy

Post by seaurchin1969 » Thu Apr 16, 2015 8:47 pm

Yes Deano, just saw oeg sent me a pm that sounds like the ticket.
I was gonna ask about any advantage going with higher compression set up, as to how much hp difference there would be, and then having to run 93 octane.
16 X 72" Combee hull 500? Caddy dd

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seaurchin1969
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Re: 500? Caddy

Post by seaurchin1969 » Sat Apr 18, 2015 3:45 pm

What do you guys make of this prop adapter.
Image

Image
16 X 72" Combee hull 500? Caddy dd

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Re: 500? Caddy

Post by Striker543 » Sun Apr 19, 2015 9:21 am

I think sidejobs ran one like that in his most recent caddy boat. I like it because it gets the engine weight a little further forward in the boat.

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Re: 500? Caddy

Post by SWAMPHUNTER45 » Sun Apr 19, 2015 7:33 pm

It aint for me not gonna put the extra stress on my crank!

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sidejobs
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Re: 500? Caddy

Post by sidejobs » Mon Apr 20, 2015 7:47 am

That one is def too long ! I run a 6". I also don't like the bolts that are being used to fasten it to the crank, especially with no washers !
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seaurchin1969
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Re: 500? Caddy

Post by seaurchin1969 » Mon Apr 20, 2015 2:45 pm

sidejobs wrote:That one is def too long ! I run a 6". I also don't like the bolts that are being used to fasten it to the crank, especially with no washers !
I agree on the bolts, looks like the bolt heads are too close to the shaft to use washers( unmodified washers anyway).
What are your concerns with the length? Just pretend this is my first real boat, and I don't know anything lol.
16 X 72" Combee hull 500? Caddy dd

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Re: 500? Caddy

Post by Junker » Mon Apr 20, 2015 8:42 pm

What are your concerns with the length? [/quote]


Imagine your holding an 8" grinder in your hand............hold it close to your body and hit the trigger...........now hold it at arms length and hit the trigger.
Now multiply that x 1,000 = undo stress on your crank.
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crowhater
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Re: 500? Caddy

Post by crowhater » Tue Apr 21, 2015 10:34 am

Please take that thing off your boat. There is no way that thing is 100% in balance, it is doing BAD THINGS to your crank shaft and main bearings. It is also a very dangerous POS! Does anyone think that thing has passed any kind of stress testing? An Alum adaptor that long, going from hot to cold, vibrating, yeah I not getting any where near the back of that boat.

Don't let my lack of current activity on the forum confuse you, I do know more than a few things about Cadillacs and airboats. This set up is BAD JUJU!!!
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seaurchin1969
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Re: 500? Caddy

Post by seaurchin1969 » Wed Apr 22, 2015 1:02 am

Striker543 wrote:That's a Q blade and you're way over spinning it. Bring it down to 2800 rpm and I bet you see a big performance increase. Also, I would get a new hub to bring your diameter out to 72" or 74".
Ok so if I can get a long hub, will my current blades fit it?
Would the extended prop adaptor accomplish the same thing ie allowing more air to the prop?
Seems like if I take anyone's advice a new prop adaptor may be in my future.
16 X 72" Combee hull 500? Caddy dd

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Re: 500? Caddy

Post by Striker543 » Wed Apr 22, 2015 8:08 am

Yes, your blades will fit in any of Sensenich's hubs (short, medium or long). A medium hub should put you at 72" and a long at 74". Personally, I would want as long of a prop as possible given the size of your hull. If you call Sensenich, they may be able to offer you some sort of trade for your current hub.

Crowhater is giving you good advice. Yank that adapter/extension off. You should be able to find a used adapter for around $75 I would guess. If you still want the extension, I would talk to some of the guys more familiar with them about where to find a quality one and what the cost would be. Whatever route you take, be very careful to make sure your prop still has plenty of clearance.

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Deano
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Re: 500? Caddy

Post by Deano » Wed Apr 22, 2015 8:14 am

You couldn't have timed coming to that realization any better than you did.

Here ya go (fair used price for a brand new adapter):
http://www.southernairboat.com/classifi ... s-new.html

However you do it, be sure you use the correct bolts/washers. (And a little anti-seize goes a long way.)
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seaurchin1969
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Re: 500? Caddy

Post by seaurchin1969 » Wed Apr 22, 2015 8:52 pm

Deano wrote:You couldn't have timed coming to that realization any better than you did.

Here ya go (fair used price for a brand new adapter):
http://www.southernairboat.com/classifi ... s-new.html

However you do it, be sure you use the correct bolts/washers. (And a little anti-seize goes a long way.)
Ok I ordered a prop adapter from Justin at the above link. I had seen his add in classifieds, and oeg also recommended him. Gotta give credit where it's due.

So now I have to hunt around for a medium hub, and that would get me out to 72"? Is that correct?
So should it stick with a two blade Q or try at this point to get a three blade hub?
16 X 72" Combee hull 500? Caddy dd

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Deano
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Re: 500? Caddy

Post by Deano » Wed Apr 22, 2015 9:23 pm

Yep, medium hub will give you a couple more inches, long hub a couple more yet. If it's all stock, I'd stay with the medium hub (72").

Just because you have a big boat doesn't necessarily mean you want to add a blade. That requirement is more related to the available power because that extra blade also adds more parasitic drag to overcome.
So, no need to go to a three blade, unless and/or until after you do some upgrades on the engine.

Wait . . where you buying the engine that OEG had? If so, I'll defer to him, I'm not familiar with it or its guts.
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seaurchin1969
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Re: 500? Caddy

Post by seaurchin1969 » Wed Apr 22, 2015 10:44 pm

Deano wrote:Yep, medium hub will give you a couple more inches, long hub a couple more yet. If it's all stock, I'd stay with the medium hub (72").

Just because you have a big boat doesn't necessarily mean you want to add a blade. That requirement is more related to the available power because that extra blade also adds more parasitic drag to overcome.
So, no need to go to a three blade, unless and/or until after you do some upgrades on the engine.

Wait . . where you buying the engine that OEG had? If so, I'll defer to him, I'm not familiar with it or its guts.
Yes I intend to get his motor, if he still has it when I scrounge the cash together.
16 X 72" Combee hull 500? Caddy dd

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Re: 500? Caddy

Post by Deano » Wed Apr 22, 2015 10:49 pm

Cool Beans. That will save you some grief, for sure. :thumbleft:
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seaurchin1969
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Re: 500? Caddy

Post by seaurchin1969 » Wed Apr 22, 2015 11:15 pm

Ok just so you know where I want to be.
As I said I Am setting it up to Bowfishing from, over to the east of you guys In louisiana, I'll have generator, and coolers and another full sized adult in all likelihood all in the boat plus whatever fish we shoot.
Now I don't expect to run dry gound with all the gear and several hundred pounds of fish, but less the fish, I'd like to be able to run on the marsh, chase hogs, even have one or two in the boat, and climb a leve.
So I can run my rig as is for now and plan an upgrade.

So to run as I have suggested, is that doable in a DD application, or should I be planning on running a reduction, and different prop?
16 X 72" Combee hull 500? Caddy dd

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Re: 500? Caddy

Post by seaurchin1969 » Wed Apr 22, 2015 11:25 pm

[quote="Deano"]Yep, medium hub will give you a couple more inches, long hub a couple more yet. If it's all stock, I'd stay with the medium hub (72)

I'm not going to leave it stock, at least a mts cam & lifters valves and springs, aluminum intake, timing set. I believe that's what OEG said his motor has atm. Would that be able to take advantage of a long hub?
16 X 72" Combee hull 500? Caddy dd

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Re: 500? Caddy

Post by Striker543 » Thu Apr 23, 2015 8:03 am

seaurchin1969 wrote:Ok just so you know where I want to be.
As I said I Am setting it up to Bowfishing from, over to the east of you guys In louisiana, I'll have generator, and coolers and another full sized adult in all likelihood all in the boat plus whatever fish we shoot.
Now I don't expect to run dry gound with all the gear and several hundred pounds of fish, but less the fish, I'd like to be able to run on the marsh, chase hogs, even have one or two in the boat, and climb a leve.
So I can run my rig as is for now and plan an upgrade.

So to run as I have suggested, is that doable in a DD application, or should I be planning on running a reduction, and different prop?
Plan on a reduction. I've seen some Caddy boats that run dry well (mine included), but on light hulls and without a big load. I think you're talking some serious power to push a 16x8' aluminum hull over a levee with a load.

That said, I would probably use your boat while you save pennies and buy a different boat when you're ready. Not only would you have to change your engine stand at a minimum to add a gearbox, caddys don't make great engines for gearboxes without spending lots of money in upgrades. If you do a search, there are endless threads talking about problems and challenges with running a caddy with a gearbox.

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Re: 500? Caddy

Post by Deano » Thu Apr 23, 2015 10:25 am

seaurchin1969 wrote:
Deano wrote:Yep, medium hub will give you a couple more inches, long hub a couple more yet. If it's all stock, I'd stay with the medium hub (72).
I'm not going to leave it stock, at least a mts cam & lifters valves and springs, aluminum intake, timing set. I believe that's what OEG said his motor has atm.
Would that be able to take advantage of a long hub?
Given fresh heads, proper cam and springs, and well worked carb, I would say yes, a long hub would be advantageous.
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but it is not the path to knowledge; it has no place in the endeavor of science."
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Re: 500? Caddy

Post by One Eyed Gator » Fri Apr 24, 2015 8:15 am

Motor has .040 MTS pistons and DD1 cam, comp lifters, MTS spring kit, cloyes timing set - advanced 3 degrees, Heads - 3 angle valve job, brass guides, Springs shimmed for proper pressure, PEP reconditioned rods with new bolts. Light weight Pulleys. Heads and block decked just enough to make the true.
Nothing fancy but built correctly.

Turned a 72" Q almost 3rd mark set a little less with 3 bld H, pushed good with both but different.

I personally do not like anything over 72". With a heavy boat I think a little more pitch helps it get out of the hole better, Also the longer the prop the more stress on the crank. I would have like to try an NGQ but my cage would only let me run a 72" prop. NGQ would have a 74" in my med hub.

Had it on a 14' Alumitec, ran very good only reason I change was my hull had 16" sides and set very low in the water, that and I was given a 5.3 vortec and got a box for cheap. Boat is much safer now.

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Re: 500? Caddy

Post by Deano » Fri Apr 24, 2015 10:07 am

SeaUrchin1969 . . . best you scrounge as quick as you can.
That engine will compliment nearly any Caddy effort for less than it would cost to replicate. 8)

Since you have Q blades, I would follow OEG's lead with a med hub as he has more experience with them.
My blade preference is different and I additionally overlooked the fact that was what you already had in hand.

I am a believer in the theory that diameter trumps pitch, as longer blades are generally more efficient. Obviously, the degree to which this becomes readily discernible varies depending on what blades you are using, but using shorter blades is like loosing crank weight, in that doing so will gain you 'snap' and quicker engine acceleration if your primary use takes advantage of that. Given a big (for a DD) boat like yours or mine, that snap is largely inconsequential, so I tend to opt for the more efficient end of the spectrum when that is the case.

For what it's worth, I don't really get excited about the additional weight of the longer hub vs a medium because that difference is less than what the factory torque convertor weighed, and they have been spun millions of miles without having crank issues. Most Cadillac crank problems come back to clearance and oiling issues, with the notable exception being with the 425's, whose problems come back to their 17 lb. weight loss that ultimately left them plain freakin' weak.
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Re: 500? Caddy

Post by One Eyed Gator » Fri Apr 24, 2015 11:55 am

I like the signature blades and think they push well, just never had the opportunity to try them.

But if I had the Q in a 72" I would stick with it. By far the best pushing prop I tried was a 72LXL38 Wood Florida Air Prop. That prop worked prefect turned 2950 but would never run a wood prop over a carbon prop just for safety.

3 blade H was fun but like a 2 stroke only pushed when it was in the 10% of it's ramp range and man was it loud. Q work great fishing when we had 3 people and 2 ice chest and gear. It would still cross dry ground and I could pull up and turn around.

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