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N2DEEP
03-28-2004, 12:17 PM
I Splashed Livewire and did some 25 Hydromotive prop testing Fri. Next time iI take a co-pilot,, I must have looked pretty stupid to the bass boat guys in the coves as I stared at my GPS wedged between my legs and roared down the empty lake. Anyway, my top revs were 4300 and speed of 64. Serious chine walk around 63 and boat trying to lean to the right . Very smooth and nice midrange, good to 60. 40MPH or better {I think, my notes blew out}at 3000- nice fast cruise. Would you have Hydromotive re-work this prop, maby cut it down, or forget it and go with something else?? I also have a 25 cleaver to try soon. Thanks for any opinions. N2

bigman
03-28-2004, 01:05 PM
I put a 350 mag in my 68 18' clasic,I experienced about the same thing. I have a Bravo 1,LH rotation. No GPS but my Gaffrig speedo said 62 when it started to chinewalk, about the same RPMs, with a 23 Mirage on it, riding by myself. I put 100lbs of weight in the front,(sand bags). I gained about 3 mphs before it starts again, it also made a big difference in how it handles. I know I'm not as smart as some of the rest of the folks on here, but my gut tells me it has alot to do with how the weight is distributed in the boat. I have trim tabs, it did a little. I want to put alum manifolds on it and I have a 25 to try also.

Rootsy
03-28-2004, 01:10 PM
hmmmmm interesting... i've run a few hydromotives (25, 26 & 27 QIV O/T & 24 & 25 QIV)... chinewalk is not a big issue unless i blatently overtrim or get into confused water... but this is at 75+ in a 16 classic... i can run 65 and take my hands off of the wheel (not recommended) and she goes straight and true... granted this is with an alpha SS which is kinda short.

before you go modifying the prop, just for piece of mind, look at a few things...

1. excessive loosness in the gimble
2. trim tabs? were they retracted all of the way?
3. trim position - chinewalk will develop in an overtrimmed position
4. condition of your gearcase and skeg
5. irregularities in the bottom of the hull

what rotation? right hand? on a right hand rotation torque reaction should force the boat to the left for list (opposite direction of prop rotation).

the BBC may really be giving you fits due to the extra weight in the arse messing up your CG location vs a sbc boat... i think reddog has encountered some of this with genuine trouble in the past...

i personally have not encountered a list on my 16 with the hydromotives... they are extremely solid running and i can run 9 - 10% slip from 3000 rpm to WOT (5500 + rpm)... the quad IV also wants to run very flat on my 16... not a lot of bow lift (stern drop)... the O/T on the other hand gives more bow lift (sucks the stern down)... i find that just a tick past neutral trim is the best position for the quad IV... and a bit more on the O/T...

i am actually going back to the O/T after testing with one last fall.. it runs slip for slip with the bigger QIV after some gearcase modification.. with just about the same handling but a bit more bow lift... which i can adjust for... and it pops my rpm up 300 - 400 and speed 2 - 3 mph...

cigarette30
03-28-2004, 02:23 PM
N2DEEP,

Sorry to say, something's really wrong. A 330 would run 72-74 (radar, not g.p.s) from the factory, with a Merc. 25 Cleaver, some had "extra cup" (stock 25" would over rev)

The chime walking was only over 70ish, and could be "driven out", HOWEVER serious point made about checking the steering, any looseness was magnified.

In the late 70's, early 80's, props were not any where as advanced, I would do some serious homework with a couple leading shops, you won't be disapointed.

The other point, are you running in the correct R.P.M. range of you motor, seens low, and is the motor performing at peak ? And yes, get those "tabs" all the way out of the water, not there for the weak, or true top end.

N2DEEP
03-28-2004, 02:42 PM
Rootsy, thanks.
1. I can wiggle the outdrive about 1.5 inches before the steering wheel moves.

2. Tabs up

3. Trim may have been excessive. It seemed to actually pick up speed/revs as it began to cavitate.

4. No known issues with gear case/skeg.

5. Hull on a roller trailer for 26 years. I can't SEE anything but....

6. LH rotation, lefty steering.

7. Slip is around 8%

8. Yes it is heavy in the rear, I soaked myself again stopping too quick.

I kinda feel it doesn't want to handle as much diameter on the prop and I had a lot of throttle left at speed.
27 cleaver was 68@ 4800 last fall around 20-22% slip. I was told this motor runs best at 5200 by previous owner.

Any engine issues should I check? My mechanic said it was strong last fall, but he admitted to being rusty with Holleys and "old" technology.

cigarette30
03-28-2004, 04:44 PM
N2DEEP,

Did not get a chance to reply with a P.M., but I can do one better than offer you vacation advise in Ocean City .... get me your dates, 30' Cigarette and a 04, 22' Donzi will await your ride. Also, if you don't already know, never miss "Seacrets" niteclub. Keep in touch.

Oh, 1 1/2 inches of play, way to much, there is most of you "chime walk" problem.

Doug L.
03-28-2004, 05:13 PM
Cig 30
I love Ocean City was there last July can't wait to get back.
One of the best places to vacation! :) :) :)
Doug

Oh yea almost forgot Yes 1.5 in. of play is way to much check the
gimble ring I fixed mine and my boat in newer then yours. :)

cigarette30
03-28-2004, 05:25 PM
Doug L.

Same offer goes for you, I guess if we have enough people, well, we will just run the boats all day ......

N2DEEP
03-28-2004, 06:09 PM
Cig, thanks I will take you up on your offer. If it cooperates, I can bring the '94 Viper to play on land. I will keep in touch. Greg

smoothie
03-28-2004, 06:47 PM
N2Deep,
Before ya start changing a bunch of stuff,give her one more shot,but this time get it trimed out at around 50mph,you know when the bow is riding high and the boat leans too the right alittle and drop your right trim tab just enough to level the boat then let it rip :yes: This is what I have to do with mine in smooth water with full hydro steering.In some nice chop its not a problem.Damn nice lookin boat,I like the color and the engine hatch :cool:

Doug L.
03-28-2004, 08:27 PM
Another thought be sure to check the tiller arm see if it is a square type
or a splined you want the square one. If you have the splined type and it
is loose it needs to be fixed right away or sooner.
when I am trimed in to much the boat wants to roll and plow
the bow I start bumping the trim out until I feel it free up and keep rolling
the throttle on.
I don't dip my tab though.
Doug

Rootsy
03-28-2004, 08:30 PM
i donno doug.. every time i've ridden with you it is WOT or idle... porpoise? ah hell just bury that throttle it'll beat itself out LOL :D

when do i need to grab the torque wrench and come over????

i'll have fresh data for you tomorrow...

JR - mr engraver tonight...

mattyboy
03-28-2004, 08:40 PM
I put a 350 mag in my 68 18' clasic,I experienced about the same thing. I have a Bravo 1,LH rotation. No GPS but my Gaffrig speedo said 62 when it started to chinewalk, about the same RPMs, with a 23 Mirage on it, riding by myself. I put 100lbs of weight in the front,(sand bags). I gained about 3 mphs before it starts again, it also made a big difference in how it handles. I know I'm not as smart as some of the rest of the folks on here, but my gut tells me it has alot to do with how the weight is distributed in the boat. I have trim tabs, it did a little. I want to put alum manifolds on it and I have a 25 to try also.

Bigman
judging by your avatar looks like you have a barrelback??? if so their hull design has different handling characteristicts than standard 18 classic,That the barrell back owners can comment on more
where's Stittvile?? get that boat to the dustoff!!!
looks like Cliff's or Penbroke's sister boat

Matty

ToonaFish
03-28-2004, 08:41 PM
JR - mr engraver tonight...

Hydrallic steering is not worth serving jail time for counterfeiting...

N2D - the visual of you doing flybys with whilst watching your lap... priceless!

Bunches,

Celene "pleased to hear that Doug doesn't have a dippy tab"

bigman
03-28-2004, 09:52 PM
Matty , I don't know if it's a barrelback. It does have a round back but like I said I'm not as sharp as some of you folks. I'd be interested in finding out. Stittville is in central N.Y.,about 5 miles north of Utica, town is even smaller than it sounds. I run my boat in Black Lake, which is northern N.Y. up by the St.Lawrence, by Ogdensburg. I still don't know how fast my boat is, I can only ring it out when there are 4 people in it. What's a dustoff? Thanks for any info, bigman.

boxy
03-28-2004, 10:18 PM
Bigman, if you can't make the DustOff, look into the 1000 Islands Donzi Run, it would be a pretty short haul for you.
Damn, Ogdensburg, we're almost neighbors, I'm in Johnston at the border about 5 times a week...

RedDog
03-28-2004, 10:27 PM
Had the big block (strong parts - 400+ HP) on a King Cobra 18 Classic. Would start the chine walk at around 70 and 5000 RPM. 1.43 drive gear ratio and a 22" OMC Raker prop.

Yes it is a lot heavier in the rear than a small block - That price never bothered me :biggrin: I love my new 22 but it ain't the same as the 18! Makes you understand why folks have to have one than 1 classic....

mattyboy
03-29-2004, 05:37 AM
Matty , I don't know if it's a barrelback. It does have a round back but like I said I'm not as sharp as some of you folks. I'd be interested in finding out. Stittville is in central N.Y.,about 5 miles north of Utica, town is even smaller than it sounds. I run my boat in Black Lake, which is northern N.Y. up by the St.Lawrence, by Ogdensburg. I still don't know how fast my boat is, I can only ring it out when there are 4 people in it. What's a dustoff? Thanks for any info, bigman.


Bigman,
the dustoff is a gathering in June on lake george about an hour north of albany, there's one in sept. there as well , plus as boxy said in aug theres a gathering up in Alexandria bay 1000 isles these are great chances to see meet and talk shop with donzi gurus and fanatics you won't regret it

The barrelback has a sharp keel and inner strakes that run all the way to the transom on a non barrelback the keel is rounded and the inner strakes stop a couple of feet short of the transom. this causes the 2 boats to ride differently but I'm not the expert on that you need to Talk to bertram boy, CDMA or Pearson or Penbroke they all have barrelbacks and can tell you about it.

which one does the back of your boat look like 1 or 2

do you know the hull number??

isn't great that when you search for 2 varying types of Donzi's you find them in one man's collection??? next you'll tell me there's a bench seat hornet there or a rare 14 :) ;) :tongue:

Matty

bigman
03-29-2004, 08:33 PM
Matty, the inner strakes run the full lengh of the boat, the keel is sharp.I never knew that there was more than one type of hull.I found a number on it one time,C18-143. At the time I did not know what the number was, I wrote it down and have not been able to find it again. I 've had the boat split before, maybe it was in there.Is there any significance to a barrelback Donzi? Thanks for the info on the dustoff, traveling any place but camp is tough right now too many things going on. Might be able to make the one at the 1000 Islands though, sure would be fun to hangout with folks that don't think my boats from Italy. Boxy, we are almost neighbors. Black Lake has got its share of power boats, but only one Donzi, Sure would be fun to see another one there, E mail me if you're ever around the area.Thanks alot for all the info, bigman.

mattyboy
03-29-2004, 09:11 PM
Bigman,
no nothing special bout a barrelback :eek: ;) you need to drop a line to the members that have them. don't loose that number very important!!


Matty

Brad Lyon
03-29-2004, 09:24 PM
N2Deep, is this the boat that was for sale through Classic Auto Showplace in Madison Heights Mi. a little while back?

Brad

N2DEEP
03-30-2004, 06:06 AM
N2Deep, is this the boat that was for sale through Classic Auto Showplace in Madison Heights Mi. a little while back?

Brad

Brad, yes I purchased it last fall, after seeing it on ebay and the Registry. It has its flaws but I REALLY like it. :biggrin.: Worked with David Clack, good car guy, did not know much on boats. I liked the black 427 Vette he had at the time, + a lot of the other cars also. N2

PS Nothing like the internet to help you spend the $$$$$.

Brad Lyon
03-30-2004, 11:21 AM
I thought so. They are about 300 yards from my house. I bought a 1981 DeLorean with 2000 miles on it from them a while back. It now has 2300 miles on it. For sale if anyone is looking!

Brad

N2DEEP
03-30-2004, 09:39 PM
Another thought be sure to check the tiller arm see if it is a square type
or a splined you want the square one. If you have the splined type and it
is loose it needs to be fixed right away or sooner.
when I am trimed in to much the boat wants to roll and plow
the bow I start bumping the trim out until I feel it free up and keep rolling
the throttle on.
I don't dip my tab though.
Doug
1. Is this the tiller arm? Square or splined?
2. Bolts with cotter keys are a bit loose, can I just tighten them? Seems that most of my play in the steering is located at these 2 points.

Doug L.
03-31-2004, 11:29 AM
Greg
The tiller arm is through bolted to the steering rod in the photo (the first photo) it is black and gose out the back of the boat. The shaft to the gimble ring is splined or square that where you have to check for play and wear.

So the steering rod bolts to the tiller arm the tiller arm bolts to the shaft the shaft gose in to the gimble ring (splined or square) and sometimes can be tighten with the 2 bolts on the gimble ring.
Hope this helps
Doug

smoothie
03-31-2004, 08:25 PM
N2D,
This is what Doug is talking about check to see if you have the two bolts on the gimble ring,if so you have a square one and should get the clamp bracket kit,hope this also helps!