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29-03-2006, 04:32 PM
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#41
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Senior Member
Country: netherlands
Location: Mijdrecht/holland
Occupation: truck repair
Interests: fast boats/porches
Boat name: bernico cat
Boat make: bernico 26 cat 2x 2,5,s
Engines: merc,s 2,5 EFI,s
Cruising area: ijselmeer
Join Date: Dec 2005
Location: Mijdrecht/holland
Posts: 382
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The difference is pulling or pushing ,is the thickness of the rod .
the rod is +- 20% of the piston diameter .
so I think you may say that it is 20 % stronger ,or weaker by the same pressure.
The reason you see the side mount rams always mounted at the right side from the drive ,is that normally every drive /engine is turning the prop RH ,clockwise.
That way you have the piston side with the most surface to push against the oil,to fight the paddle wheel force.
LH or counterclockwise lowers should run the ram on the left side off course.
sterling
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29-03-2006, 04:42 PM
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#42
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hello
Join Date: Mar 2004
Posts: 2,739
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What I meant when I was responding to Jons statement about the other end of the drag link is that if the drag link is what I think it is (the link bar that attaches the ram to the tiller arm?) then the seastar rams doesnt have one. So the bolt at the other end is not an issue as it doesn't exist on seastar.
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29-03-2006, 04:50 PM
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#43
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hello
Join Date: Mar 2004
Posts: 2,739
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Don't get me wrong I'm not trying to say that Seastar Pro is better or even as good as the Latham and Marine Machine side ram setups I'm just saying that in my opinion with an ARP tiller bolt and the correct maintainance shedule its perfectly adequate for the typical sub 300hp 20ish foot 80ish mph boat.
I'm not trying to stir it up or anything but the Seastar Pro helm is 1500psi and thats 50% more than a Capilano
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29-03-2006, 05:27 PM
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#44
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Traveling
Country: UK
Location: Alderholt
Occupation: Aerospace
Boat name: T/T D2S
Boat make: Midas 27' Cat, Argo 16 Cat. Avon Rib Thingy
Engines: Merc 280-ROS -JSRE,65Xs, 75 Stinger, Yam 60
Cruising area: Any Seedy Bar
Join Date: Sep 2004
Location: Alderholt
Posts: 4,225
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I agree, If Merc make it that way then it can be used that way.
As a very sweeping statement I see other issues as
A "THE" Bolt (cond)
B Hydraulic lines that tend to be forgotten about
C Helm maint
D C&M of the system inc fluid quality
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29-03-2006, 07:14 PM
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#45
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Registered User
Join Date: Mar 2004
Posts: 5,724
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so how many failiures has seatar pro had then?
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29-03-2006, 07:22 PM
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#46
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Registered User
Country: UK
Location: Weston Super Mare
Occupation: Electrical Engineer
Join Date: Mar 2004
Location: Weston Super Mare
Posts: 6,351
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Quote:
Originally posted by Gav
so how many failiures has seatar pro had then?
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Its not the steering that fails but the bolt that attaches the ram to the tiller arm
Dunno how many have failed but you read about it on S and F but they are all doing over the one er
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29-03-2006, 07:27 PM
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#47
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Registered User
Country: Job Centre
Location: In a box
Occupation: Chaos's gofer
Interests: Skiving
Boat make: Spectre 30
Engines: 2 x Promax 225
Cruising area: In the bath
Join Date: Mar 2004
Location: In a box
Posts: 5,201
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I really don't think you need to have a failure to know that there are better alternatives out there!
For the money, Seastar is superb, and in the right application, almost failproof, but if I was building a quicken, I'd be fitting a decent sidemount system! It really isn't that much more money in the great scheme of things.
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29-03-2006, 07:33 PM
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#48
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Registered User
Location: GOLDEN MILE
Boat name: LILY THE PINK AND TERMINATOR 11
Boat make: PHANTOM 21 AND 20
Engines: 2.5 EFI X 2
Join Date: Mar 2004
Location: GOLDEN MILE
Posts: 2,475
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A mate of hutchy's had one fail, I think he said the casting broke, boat was a 24 ring with twin xr2's, it nearly killed him .
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29-03-2006, 07:35 PM
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#49
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Registered User
Country: Job Centre
Location: In a box
Occupation: Chaos's gofer
Interests: Skiving
Boat make: Spectre 30
Engines: 2 x Promax 225
Cruising area: In the bath
Join Date: Mar 2004
Location: In a box
Posts: 5,201
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Was that a red and white one, with bobs exhaust reliefs?
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29-03-2006, 07:37 PM
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#50
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Registered User
Location: GOLDEN MILE
Boat name: LILY THE PINK AND TERMINATOR 11
Boat make: PHANTOM 21 AND 20
Engines: 2.5 EFI X 2
Join Date: Mar 2004
Location: GOLDEN MILE
Posts: 2,475
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Quote:
Originally posted by Tony Davis
Was that a red and white one, with bobs exhaust reliefs?
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No, a pink one.
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PLEASE DON'T STEAL...THE GOVERNMENT DON'T LIKE THE COMPETITION
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29-03-2006, 07:38 PM
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#51
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Registered User
Country: Job Centre
Location: In a box
Occupation: Chaos's gofer
Interests: Skiving
Boat make: Spectre 30
Engines: 2 x Promax 225
Cruising area: In the bath
Join Date: Mar 2004
Location: In a box
Posts: 5,201
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I know that one, think it used to live in Newcastle!
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Chaos for Moderator.
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29-03-2006, 07:40 PM
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#52
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Registered User
Country: uk
Location: dorset
Interests: wasting money on boats
Boat name: aquilla .
Boat make: Superhawk 40. Ring 21E. Seadoo gtx. Windy Khamsin
Engines: Kad 300s. 300xs Dbr .d6 370 230 4tec
Cruising area: corfu
Join Date: Mar 2004
Location: dorset
Posts: 570
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For the money, Seastar is superb, and in the right application, almost failproof, but if I was building a quicken, I'd be fitting a decent sidemount system! It really isn't that much more money in the great scheme of things. [/B][/QUOTE]
WISE WORDS
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29-03-2006, 07:41 PM
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#53
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hello
Join Date: Mar 2004
Posts: 2,739
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Did a bit of research and this is what I came up with:
The tensile strength for ARP’s bolts is 160,000 lbs/in2 (square inches) and its shear strength is 95,000 lbs/in2. According to some chap on S and F the tensile strength for 304 stainless bolts is 70,000 lbs/in2. Apparently the ultimate shear strength of a fastener is typically about 60% of its ultimate tensile strength so for a 304 grade bolt I guess its about 42,000 lbs/in2
So:
Using a 0.375-inch (3/8) diameter ARP bolt gives you the following shear capability:
A = Cross-sectional area of the fastener size (since bolt bodies/shanks have circular cross-sections, use area of a circle) = Pi x r2 where R (radius) = 0.375/2 = 0.1875, therefore A = Pi x (0.1875)2 = 0.1104 in2
Capability in shear for a 3/8 ARP bolt = 95,000 lbs/in2 x 0.1104 in2 = 10488 lbs
Using the a 0.625-inch (5/8) diameter 304 stainless bolt gives you the following shear capability:
A = Pi x r2 where R (radius) = 0.625/2 = 0.3125, therefore A = Pi x (0.3125)2 = 0.3068 in2
Capability in shear for a 5/8 304 stainless bolt = 42,000 lbs/in2 x 0.3068 in2 = 12886 lbs
The above information/calculations came from
here. I just substituted the numbers for the different sizes and tensile strengths. The final figures won't be exact as I used major diameters (I didn't know minor diameters) plus my/their calculations could be complete bollox
I know on that site the figures it gives for the ARP fastner don't actually say that its the stainless one but the info I found on S and F about the stainless bolt quoted it at 170,000 lbs/in2 tensile strength so I guess it either is the one or is of similar strength to the one mentioned here.
Also found this statement on the above site regarding the brittleness of the bolts:
"I’ve also heard the argument that grade 8’s are more brittle than grade 5’s and that’s why you shouldn’t use them. Well, first you need to understand what the term “brittle” really means. Brittleness in bolts is defined as failure at stresses apparently below the strength of the bolt material with little or no evidence of plastic deformation. Typically, fasteners are not brittle below 180 ksi ultimate tensile strength. Grade 5’s have an ultimate tensile strength of 120 ksi and a grade 8 fastener has an ultimate tensile strength of 150 ksi. This is why brittle is a relative term. Nearly all fasteners are considered ductile except some made from PH 15-6 Mo, 17-4 PH and 17-7 PH."
Make of it what you will!!!
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29-03-2006, 07:44 PM
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#54
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hello
Join Date: Mar 2004
Posts: 2,739
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Quote:
Originally posted by Burty
Its not the steering that fails but the bolt that attaches the ram to the tiller arm
Dunno how many have failed but you read about it on S and F but they are all doing over the one er
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Seastar supply the tiller bolt buts its just a plain nothing special stainless item, get an ARP replcement from mercury!!!
The following are all ARP steering bolts (all the same material, just different lengths)
Mercury #
10-849838 = 1.25"
10-875273-138 = 1.38"
10-875273-150 = 1.50"
10-875273-162 = 1.62"
Seastar pro 3/8's, 1-1/4 NF Bolt.
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29-03-2006, 07:46 PM
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#55
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Registered User
Country: Job Centre
Location: In a box
Occupation: Chaos's gofer
Interests: Skiving
Boat make: Spectre 30
Engines: 2 x Promax 225
Cruising area: In the bath
Join Date: Mar 2004
Location: In a box
Posts: 5,201
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Quote:
Originally posted by Rockey
WISE WORDS
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Especially when your spending someone elses money!
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Chaos for Moderator.
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29-03-2006, 07:48 PM
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#56
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hello
Join Date: Mar 2004
Posts: 2,739
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Quote:
Originally posted by Tony Davis
if I was building a quicken, I'd be fitting a decent sidemount system! It really isn't that much more money in the great scheme of things.
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What do you consider a quicken?
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29-03-2006, 07:50 PM
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#57
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hello
Join Date: Mar 2004
Posts: 2,739
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Quote:
Originally posted by Burty
Dunno how many have failed but you read about it on S and F but they are all doing over the one er
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You don't exactly read about it alot though do you!!!
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29-03-2006, 07:57 PM
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#58
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Registered User
Country: Job Centre
Location: In a box
Occupation: Chaos's gofer
Interests: Skiving
Boat make: Spectre 30
Engines: 2 x Promax 225
Cruising area: In the bath
Join Date: Mar 2004
Location: In a box
Posts: 5,201
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Quote:
Originally posted by Johnny Boat Dude
What do you consider a quicken?
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All depends on the size/speed etc of boat, but anything that's in excess of the recommendations of the Seastar spec is a pretty good starting point.
Out of interest, when we were building the Honda Boats, we fitted as standard Hynautic front mount steering systems. The only failure we had was with a boat whose owner had gone for a seastar system!
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29-03-2006, 07:58 PM
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#59
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hello
Join Date: Mar 2004
Posts: 2,739
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what part failed?
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29-03-2006, 07:58 PM
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#60
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Registered User
Join Date: Mar 2004
Posts: 5,724
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Quote:
Originally posted by Tony Davis
. The only failure we had was with a boat whose owner had gone for a seastar system!
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oh jeez i'm brimming with confidence now nobba!
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