Transom strength for hydraulic jackplate

[bear_69cuda]

Hey gang,

I asked Hurricane about adding a hydraulic jack plate on my boat for various reasons,
Below is the response I received from Nautic Global Group. Currently I'm running a Yamaha F150TXR, and my hull is rated for 200 HP. The Yamaha F200TXR is 117 lbs more than the F150, and 50 more HP.
Does anyone think a 6" offset hydraulic jackplate will stress the transom as much as the max HP and weight rating, or cause it to fail? And if so, could it be reinforced?

Hi Bryan:

Hope all is well with you and your family.

While we are aware that some people have used jack plates on our boats in the past (mostly manual), we cannot recommend their use. The use of a jack plate will add extra torque and strain to the transom which we have never measured and tested and therefore do not recommend their use. We are not saying that an issue would arise, but without thorough testing, it would be a concern and if an issue were to occur that could be construed as resulting from the use of the jack plate, the warranty on the transom would be voided.

Sorry it's not the answer you were hoping for, but better safe than sorry.

Clint

 

[Bondo]

Re: Transom strength for hydraulic jackplate

And if so, could it be reinforced?

Ayuh,... Anything is Possible....

I would Think your transom/ hull would handle the added stresses,... But I can't see it...

 

[69rrvert]

Re: Transom strength for hydraulic jackplate

Check out the "boating" section on www.2coolfishing.com/ttmbforum/ . Everyone down here (Texas Gulf Coast) runs hydralic jack plates with the 300 hp engines. Heck, I'm running a 6" offset hydralic with a 6" setback plate on my Alweld aluminum boat with a 115 Evinrude. I say install the jack plate and never look back. Go to Youtube and check out the videos on the "SCB Stingray" or look at his post on 2cool. Thanks, Steven

 

[bear_69cuda]

Re: Transom strength for hydraulic jackplate

Thanks for the replies dudes...

I'm worried about a few things...

The greater the setback, the greater the static rotational torque. But I figure if the transom can handle the F200TXR weight and it's extra torque, it should be fine...
Force multiplied by Distance = leverage
My transom needs to be strong enough to resist this increased torque.
I don't believe shift in the center of gravity would be significant..

I have discussed this with a local glass boat builder, he also thinks it should be okay, and plan on him looking at my transom this spring to assess...

Any structural engineers out there? Anyone have a magical formula?

 

[Bob_VT]

Re: Transom strength for hydraulic jackplate

Maybe a call to Hurricane direct?????

Nautic Global Group
4500 Middlebury Street
PO Box 1158
Elkhart, IN 46516
Phone 574.522.8381
Fax 574.522.5120

 

[bear_69cuda]

Re: Transom strength for hydraulic jackplate

Hi Bob,

I did that first thing... I posted Clint Hardy's (Nautical Global Group) response at the beginning of this thread...

 

[j_k_bisson]

Re: Transom strength for hydraulic jackplate

I've been sitting here all morning trying to figure out how to set up this problem with the avaiable information and what I can pull from the internet. And basically I come up with is this.

Your failure modes are as follows

1) Bolts break/shear = Assume same bolt size between motors and applications and this issue resoves itself. If in doubt use grade 8 bolts. They are rated for 21500-24000lbs shear force per bolt (1/2' bolts).

2) Added strain to transom = Your transom is rated to hold and sustain maximum repetative impact forces. To try to figure out with available info is impossible. With alot of assumptions can be done. But not acurately. Over the long run it will slowly work on your transom. But any motor does. Possible backing plate or reinforcement to help stiffen transom from inside? Possible.

Here is the thing;

Boat builders "design" to meet a spec. They design and build a couple of prototypes and then subject them to destructive testing. If the boats pass this testing then new boats are submitted to the approprate goverment testing board and retested to validate certifications. If they fail then they upgrade/change the design with direction from someone with experience in boat design. (add this gusset here, make this thicker there, etc) Alot of times they don't even make a whole boat just the transom area. This heps keep costs down. Anyways this is expensive and time consuming process. After it is done, they will incorporate all the leasons learns into other boat with simular features/designs. Trying to avoid the costs of development. That is why the factory gave you the answer they did. They did not test for the situation you are asking about.

The place you should be asking you questions is to the jack plate manufacture. They are required by law to test their product to meet the same standards. If they do not have a tested/approved product and can not list the spec's they meet, you may want to go with a different brand. Because putting on an unapproved jack plate will void your boat hull warranty, you insurance for the boat, and make yourself liable if injuries are incured. So do your research.

Sorry not the answer you where looking for. But it is the Engineers answer.

 

[NSBCraig]

Re: Transom strength for hydraulic jackplate

There really shouldn't be any kind of problem.

 

[bear_69cuda]

Re: Transom strength for hydraulic jackplate

Here's the heartfelt, warm, detailed, full of great information response form Atlas Jack plates INC.

"Hi Berry,

I can't answer it is a question for the boat mfg. I do not know how the boat is built.

Thanks
Brandy"

 

[j_k_bisson]

Re: Transom strength for hydraulic jackplate

Here's the heartfelt, warm, detailed, full of great information response form Atlas Jack plates INC.

"Hi Berry,

I can't answer it is a question for the boat mfg. I do not know how the boat is built.

Thanks
Brandy"

I would reask the question does you product meet UGCG certification. All products bolted between the motor and the transom assume the same responsibilities as manufactures have when they make a boat. Then if you get the same response, I would ask how did they come to the HP rating they are advertising. Was it through testing? And then what tests where performed? And to who's specification?

Untimately you may have to just contact you insurance and ask the question about what you are doing. If it is insured. If they are going to insure it then you are good to go.

 

[Bob_VT]

Re: Transom strength for hydraulic jackplate

Duh! :redface: Oh I see that :redface:

Interesting how no one wants (manufacturer vs jack plate company) to say it's okay.

I imagine you will be fine. I have seen a jack plate fail and sent a Johnson 225 to a deep watery grave but it was the jack that separated ..... the transom bolts and the motor mount bolts held fine.

Okay I have the guts to say it...... GO FOR IT........ if you think it will make that much of a performance change for you

 

[Yacht Dr.]

Re: Transom strength for hydraulic jackplate

Hey gang,

I asked Hurricane about adding a hydraulic jack plate on my boat for various reasons,
Below is the response I received from Nautic Global Group. Currently I'm running a Yamaha F150TXR, and my hull is rated for 200 HP. The Yamaha F200TXR is 117 lbs more than the F150, and 50 more HP.
Does anyone think a 6" offset hydraulic jackplate will stress the transom as much as the max HP and weight rating, or cause it to fail? And if so, could it be reinforced?

Hi Bryan:

Hope all is well with you and your family.

While we are aware that some people have used jack plates on our boats in the past (mostly manual), we cannot recommend their use. The use of a jack plate will add extra torque and strain to the transom which we have never measured and tested and therefore do not recommend their use. We are not saying that an issue would arise, but without thorough testing, it would be a concern and if an issue were to occur that could be construed as resulting from the use of the jack plate, the warranty on the transom would be voided.

Sorry it's not the answer you were hoping for, but better safe than sorry.

Clint

There is your answer to your question m8 ...right from the factory !

They have not tested it..and they dont recommend it ( or showing so much concern to where your not going to be warrantied ).

What boat are you talking about..what year make ?

I would say ANY jack plate Will in fact test the strenght of the trans..but how Much is a totally different question. Its how they rate the build of the boat to be able to sell the power on the back of the boat. Not modding the boat.

Coast Guard Certification is different then CG regulations..

As Bob asked..why do you want to jack your motor ?..

Nobody is going to warranty the boat with mods after the factory ( I wouldnt ) so.. seriously consider any mod being for you..by you..safty..not warranty calls to the plant m8..

YD.

 

[69rrvert]

Re: Transom strength for hydraulic jackplate

These are the two top manufactures on jack plates. There are thousands of these all over the gulf coast. These are the only two jack plates that you will see on the boats down here. Like I said earlier, if you still have some concern, go to www.2coolfishing.net and ask around in the "boating" forum. There are several manufactures of "flats" boat that are on that site. Thanks, Steven

CMC - Cook Mfg):
Everything on this unit is concealed in one unit. Nothing mounts inside teh boat. You mount the jack plate and run the wires to the console. This is the unit that I have.

http://cook-mfg.net/cart/index.php?...=10_11&zenid=6b599fa8b8f640088ed8fa2037dcd347

Flats Jack - (Bob's Machine Shop):
This is a very good jack plate. My dad has one of these on his boat. The only bad thing about the Flats Jack is that the hydralic pump has to be mounted inside the boat with hoses ran between the pump and plate. It is a little faster than the CMC.

http://www.bobsmachine.com/Products/jackplate_hydraulic.cfm

 

[bear_69cuda]

Re: Transom strength for hydraulic jackplate

There is your answer to your question m8 ...right from the factory !

They have not tested it..and they dont recommend it ( or showing so much concern to where your not going to be warrantied ).

What boat are you talking about..what year make ?

I would say ANY jack plate Will in fact test the strenght of the trans..but how Much is a totally different question. Its how they rate the build of the boat to be able to sell the power on the back of the boat. Not modding the boat.

Coast Guard Certification is different then CG regulations..

As Bob asked..why do you want to jack your motor ?..

Nobody is going to warranty the boat with mods after the factory ( I wouldnt ) so.. seriously consider any mod being for you..by you..safty..not warranty calls to the plant m8..

YD.

Thanks for the input Doc,

The boat is a 2008 Hurricane 202FDGS 20" deck boat rated for 200 HP. I want to raise and lower the F150 for multiple reasons.
Less drag at WOT = more speed.
I love to fish and get in the shallows.
I can lower the motor for better hole shot.
I can lower the motor for better handling in rough water.

Hi Bob, Jeff, all, thanks for the all the thought with this, I really really appreciate it... I'm just trying to make a safe decision... I also plan on having my local boat builder look at it. he's seen my transom for some work he did in the bilge area and feels it's more than strong enough, but wants another look in spring. He would do any reinforcement if necessary. I feel about 60:40 installing the JP at the moment... Now Doc has me thinking it all through...

 

[bear_69cuda]

Re: Transom strength for hydraulic jackplate

These are the two top manufactures on jack plates. There are thousands of these all over the gulf coast. These are the only two jack plates that you will see on the boats down here. Like I said earlier, if you still have some concern, go to www.2coolfishing.net and ask around in the "boating" forum. There are several manufactures of "flats" boat that are on that site. Thanks, Steven

CMC - Cook Mfg):
Everything on this unit is concealed in one unit. Nothing mounts inside teh boat. You mount the jack plate and run the wires to the console. This is the unit that I have.

http://cook-mfg.net/cart/index.php?...=10_11&zenid=6b599fa8b8f640088ed8fa2037dcd347

Flats Jack - (Bob's Machine Shop):
This is a very good jack plate. My dad has one of these on his boat. The only bad thing about the Flats Jack is that the hydralic pump has to be mounted inside the boat with hoses ran between the pump and plate. It is a little faster than the CMC.

http://www.bobsmachine.com/Products/jackplate_hydraulic.cfm

I have e-mail sent Bob's regarding my situation. I will look into CMC, and 2coolfishing also,

Thanks again Steven!

 

[bear_69cuda]

Re: Transom strength for hydraulic jackplate

This is a message from Bob's Jack Plates.

"We have never had a boat that we could not install a jack plate on.

Even if you do not have a jack plate the installation of backing plates is always a good idea to help distribute the load across the transom rather than just on the mounting bolt holes."

Regards,
Mark
BMS

Another interesting tid bit..

http://forums.iboats.com/showthread.php?t=417487

 

[NSBCraig]

Re: Transom strength for hydraulic jackplate

Asking the jackplate manufacture is useless.

They didn't build your boat and there is no uscg certification or anything even remotely like that for a jackplate.

Bob's is a great company with an incredible reputation.

I included a pic of their backing plates. ( I would use them even without jackplate )

They also sell a bolt kit for installing your jackplate that includes all the washers, nylock nuts and lock washers you need to properly install the plate.

If your transom isn't rotten your fine ( actual my Baja had a rotten transom with a 6" fixed setback and a 6" jackplate for years before it came into my hands )

 

[bear_69cuda]

Re: Transom strength for hydraulic jackplate

Now this is the response I've been waiting for!

From CMC jack plates.

Hi Bryan,

Have sold several jack plates to Hurricane boat owners. In fact, one of our employees has a Hurricane 232 FD with a 250 H.P. motor. He has had one of our Power-Lift jack plates on it for 4-years with no problems.

There is more surface against the transom when you install a Power-Lift to distribute the load on a larger area than your motor has. We have been making the Power-Lift for over 28-years and have never heard of a transom problem caused by the Power-Lift.

Best regards,
Rick Presley
V.P./Marketing
CMC Marine, Inc.
800-654-3697 ext. 16
www.cook-mfg.com

 

[69rrvert]

Re: Transom strength for hydraulic jackplate

Glad you finally found your answer. You can't go wrong with the Power Lift and it is easiest of the two to install because the pump is integrated inside of the jack plate itself. You simply install the jack plate and run the wires to your console. Don't get me wrong, the Flat's Jack is a quality jack plate also but you have to mount the pump inside of the boat. Thanks, Steven

 

[Yacht Dr.]

Re: Transom strength for hydraulic jackplate

Please dont get me wrong .. as I know I have a knack of sounding ..erm.. offish.. but..

Are you planning on being completely responsible for this mod ? or do you have to have a "certified" guy install this.

I know what your going to say..but..I have done add-on mods that have in Writing to say "If a certified tech performes the installation we will warranty any damage done to the structure of the boat" ( sorry cant tell you who or what mod...lets just say its for ease of transom swimming applications ).

Or is this warranty a non issue..

YD.