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roadtrip se
09-09-2002, 11:08 AM
Took the boat to Eufala with very little seat time, having just finished her within days of the Labor Day weekend.

I noticed that over 70, the boat would put her nose down and keep it that way. I figured I must be dragging tabs and this had to be scrubbing speed and control.

Talking to the guys in the parking lot, Grizzly suggested I shorten the existing Bennett rams and Poodle suggested ordering a new set of shorter rams.

After talking to Bennett last week, I uncovered a neat little trick. These things have an internal actuator stop which can be shortened. Opened them up Saturday morning, put vice grips on the bottom ends to keep the rams extended, took a hack saw to the stop, filed the edges, cleaned up for filings, closed them up, and removed the vice grips.

Now the travel is one inch higher and they are up out of the way when running the boat!

End result? Boat nose is back up over 70 and it feels like the boat picked up a few mph. Couldn't register it, because the water was pretty choppy. Boat does fly better without doubt.

Thanks guys for the suggestions!

Now on to props. Anybody got a 15 inch+, 27 or 28 pitch three blade I could try? Mercury doesn't make it!

Todd

HP 600SC
09-09-2002, 01:14 PM
Todd, cool....I'll bet that makes the boat more drivable too. Are you bringing that bad boy to Sarasota next month for the owners rally or are you flying in?
Your friend Ted :)

Lil Grizz
09-09-2002, 02:09 PM
I cut the little stopper down last year (following dads advice). He made a little template and it took all of 5 minutes to do and only required a hacksaw and one old rag. I picked up a couple MPH but the ride is SOOOOOO much better and trimming is easier now. Downside is my rams somtime hang in the old stopping point. Almost like the rod has a notch worn into it that holds it where it used to be fully retracted. seems to be getting better and never hangs up while underway, only when on the trailer or just floating.

I might be able to post some before and after pics on what specifically needs to be trimmed. I know that when I was first told of this trick I coldnt understand what was modified until I actually saw it, but it is very simple. The extra length on the stop is supposoedly there so you can compensate for small install errors without repositioning the rams. I'll try and round up pics in the next few days.

Stuart
09-09-2002, 04:54 PM
I have the same problem. My E-drive with the prop I have wants to turn my boat over. I installed the forward edge of the tabs as per the instructions and the back side about 3/8" higher than it showed.
My bow stays down. I still need some tab on one side at all speeds.

How high are yours mounted on the forward side?

BigGrizzly
09-09-2002, 05:32 PM
I made the template so they would be cut to the maximum and be paralell to the base. you don't want to be cocked on the stop.

Randy, owner of Donzis since 1966.

roadtrip se
09-09-2002, 06:50 PM
Ted,

Flying not driving to Sarasota, so the beast stays at home. Just too many things going on this fall to add four days of driving to the mix.

That being said, the thumb is defintely out and one of the boats that I would most want to ride in is yours.

Of course, I might have a few questions....

Todd

Looking forward to that drink.

HP 600SC
09-09-2002, 08:38 PM
Todd,
there is always room for my friend and fellow
member of the HP500 club! Lookin forward to that drink too!
Ted M.

turbo2256
09-10-2002, 09:51 AM
I have noticed that my boat's Bennet tabs are parallel to the boat bottom at fully retracted position unlike the K-planes I am used to. Now the boat attitude over 60 is like what roadtrip is or was experancing and was about to go to K-planes... so show me what to cut...putting new blade in my hack saw tonight.

Stuart
09-10-2002, 10:05 AM
I'm in on the cut.

roadtrip se
09-10-2002, 12:07 PM
Tried to draw the top of the tab.

Be sure to use vice grips on the bottom of the
tab actuator to hold it in place.

Unscrew both tops if you have a twin actuator application.

Cut the stop flush with the top cap of the tab.

File and make sure it is a straight edge.

Clean up filings.

Reseal.

Top off lost oil.

You now have one additional inch of travel.

http://www.donzi.net/photos/tsomerville31.jpg

roadtrip se
09-10-2002, 12:31 PM
By the way, Donzi set these tabs up this way for a reason. To make the boat more controllable at top speed in the hands of less than experienced driver.

If you chose to do this process to your tabs, take it easy and learn what this does to your handling. Go out there and mash your throttle
the first time out of the box and your chances of going swimming are great, I promise you.

Good luck and be safe out there!

Todd

turbo2256
09-10-2002, 01:48 PM
I talked to Bennet and their spin on it is to send me some shorter caps to try before cutting.

boldts
09-10-2002, 11:28 PM
Roadtrip SE - I guess I need to start a HP525 club and change my user name to BoldtSE? See, I told you I need to plan at least an extra 10 MPH over where your at now. By May next year (working on a July date at present), you'll have that Donzi so fine tuned, I might as well just leave mine on the trailer! You've come a very long way from where we were back in February. (E-mail us for that story if you want to know) Seeing the big 5 in action at Eufaula was the biggest thrill of the weekend for me. Then getting the opportunity to ride in 2 of those 5 was absolutely the best time I've ever had in a boat! No offense Poodle and Buoy Boy, I very much enjoyed the ride in your Donzis also. Really brought back some memories of my 18' Classic ownership.

On the subject of a faster boat to keep up with you guys, I'm putting that on the back burner for now. A certain unintentional wash-down proved to me that more practice in the driving of a performance boat is needed by me. Things happen much faster at 65 than they do at 45. Class is still in session in Ohio.

Back to the subject.... Thanks for adding the tip on the Bennetts and the word of caution! :cool:

RedDog
09-11-2002, 08:48 AM
Washdown Scott B? Was more than one washdown involved in your trip to Eufala.

Signed - just looking for the towel wink

Tabman II
09-11-2002, 04:35 PM
Hi all,

I am Thomas and I work for Bennett Marine in the Client Service department. I see we have few attitude running conditions that could use a little help!!

Cutting the Upper Hinge (triangle base of actuator mounted on transom of vessel) Spacer down will work as long as you take your time and be VERY CAREFUL not to break it out of the Upper Hinge all together. Snapping it out can happen when doing this modification, which will allow the Piston to retract too far inside the Cylinder Body and put undue stress against the Lower Hinge (foot of actuator that attaches to trim tab using two screws) Pin, which will try to shear the Pin off. The purpose of the Upper Hinge Spacer is to provide the uppermost rest for the piston when the actuator is fully retracted. We will be happy to help by supplying replacement Upper Hinges that have a Reduced Height Spacer w/installation instructions at No Charge, but I will need some information on your trim tab system first. Please provide the following information on your actuators:

1. How many raised rings are there at bottom of 2” of the cylinder body, 3 or 4?

2. How much piston shaft is exposed between the 2" cylinder body and the Lower Hinge (foot that attaches to trim tab) when the tabs are fully retracted, 1" or none?

3. Do you have Trimdicators or not?

Please contact me back at our email address: trimtabs@earthlink.net and include your mailing addresses too.

I look forward to hear from all of you soon!

Sincerely,
MJ Thomas
Bennett Marine, Inc.
Client Services
trimtabs@earthlink.net
954-427-1400
954-480-2897 Fax

clayman
09-11-2002, 07:37 PM
I think I could use some extra top end. Mine run parrallel to the running surface. Is this wrong?
I like the idea of them angled up a bit if that is what we are actually talking about.
James
http://www.donzi.net/photos/jspiroff68.jpg

BigGrizzly
09-11-2002, 09:51 PM
Yes, that is it. By cuttimg the stop you actually leghthen the stroke by an inch by allowing it to go to the end of the stroke, this gives you about 4 deg of angle. If your carefull you won't loose any fluid either. Still have to admit your boat is beautiful, but after seeing your art I'm not really surprised!

Randy owner of donzi since 1966

clayman
09-12-2002, 12:22 AM
Thanks, :D sounds like I need some trimming
James

Bad-Tat
09-12-2002, 06:18 AM
Clayman,
What kind of wax do you use? That boat has a killer shine on it!!!

harbormaster
09-12-2002, 08:22 AM
Thomas,
Thanks for your posting and offer. It is great that a company will take time to actually talk to their customers. I was wondering what brand tabs to buy and now I know. Welcome aboard.

clayman
09-12-2002, 12:17 PM
Bill,
I actually haven't waxed the hull yet! It is base/clear coat urethane and the supplier told we to wait a few months before I wax it. I quess it is time though.
James

clayman
09-12-2002, 12:21 PM
Tabman II, I don't think your email link is working, I tried to email you my stats,but here they are:
4 rings, 1" space, no indicators
James Spiroff
1880 Twin Oak St
Deltona, Florida 32725

turbo2256
09-12-2002, 12:32 PM
My boat the tabs are actually angled down at full up position ... thinking of putting them on my 16 and putting twin rams on the Agressor .. for now I got to see what happens with what I have and the new capps ... Hope they arive soon ... weather wont last much longer ....

Thanks Bennet great service

Dave T.

David O
09-12-2002, 02:03 PM
Copy of the reply I recieved from a very FIRST CLASS COMPANY.

Mr. Owsley,

Thank you for the photos!

You have Standard Rivet Clearance Actuators (A1101RC) and I will send you the new Upper Hinges w/Reduced Height Spacers. These will allow the piston to retract further inside the cylinder body thereby raising the trailing edge of the tab higher (more negative angle). You should also check your installation and ensure it is per the instructions before making this modification.

http://bennetttrimtabs.com/online.html, (http://bennetttrimtabs.com/online.html) this is a link to our online installation instructions just in case you have missed placed them in your workshop. You will notice in Fig. 7 a profile of the trim tab installed. The two main things to check on are the measurement for the leading edge mounting (flush or up 1/8" from hull bottom) and the measurement between the trailing edge & straight edge off the hull bottom (1/2" for 9" Chord tabs). As long as you system is mounted in
this fashion, then after installing the new Upper Hinges you should have a measurement very close to 1-1/2" between the trailing edge of the tab
and the straight edge off the hull bottom. If you find your installation to different than our instructions, then you will need to modify your installation to gain the negative angle at the trailing edge.

Please let me know your findings, so we can help!

Sincerely,

M.J. Thomas
Client Services
Bennett Marine Inc.
www.BennettTrimTabs.com (http://www.BennettTrimTabs.com)
Phone: (954) 427-1400
Fax: (954) 480-2897

clayman
09-12-2002, 06:01 PM
I have been very impressed with Bennet also. When I first got my boat, one of the hinge mounts on my tabs was broke. I called them, and expected to buy a new one, and instead they send me two for free , not even shipping! And this is on a 16 year old boat! I wish all customer service was like that!
James

Tabman II
09-14-2002, 09:49 AM
Clayman, Turbo2256, & David O,

Thanks to all for your compliments!

David O,

Please check your mounting and let me know your findings, so we can help you out with any problems.

Clayman,

I am sorry the link didn't work, but I have your information and will mail the Upper Hinges to you Monday. Please wait for them to arrive before starting the project, since they come with installation instructions to make it go smoothly.

If you have anymore trouble or questions, feel free to contact us. We will be more than happy to help!

In Your Service,
MJ Thomas
Bennett Marine, Inc.
Client Service
954-427-1400
954-480-2897 Fax
trimtabs@earthlink.net

oldLenny
09-14-2002, 10:16 AM
David O. I couldn't get M.J. Thomas' link to work. The comma is tied in with the address. Try this one...

cistineb http://bennetttrimtabs.com/online.html

BigGrizzly
09-14-2002, 01:24 PM
Mike TabmanII you helped me on this subject over a year ago. so far I have helped 6 people with this problem. I remember trying to by shorter rams and you convincing me not to spend the money. I am Randy from American Honda.

Randy owner of Donzis since 1966

knee deep
09-15-2002, 06:16 AM
Okay guys - another project. I don't have tabs on my 18'. After checking out the Bennett site I am wondering if I am better off with regular tabs or the sport tabs? and well we're at it a hydraulic hatch lifter~hmm. Appreciate your input> eek!

RickR
09-15-2002, 07:54 AM
I agree Bennett is 1st class :D .
A few years ago I was on vacation is SE Fla when a stuck trim rocker (poor installation) caused one of the pump solonoids to fail. I went by Bennetts office to get a replacement solonoid and then handed a new pump to me!

Too bad some electronics (Garmin) companies (Garmin) aren't like that (Garmin).

turbo2256
09-16-2002, 08:35 AM
Well I got my new tops Fri. while I was out boating. Put them on Sat. everything worked per instructions and Thomas's post. They are now up 1 1/2" from being parallel. Cant wait to wet test them this Fri weather permitting.

Thomas it looked to me the spacers just snap in and out and snaping the shorter ones in the old cap would have worked?
Thanks again for the quick service Bennett

DaveT

clayman
09-19-2002, 12:19 PM
I received my shorter parts on monday, but haven't had time to install them. Any body test theirs yet? Did it help the top end? handling?
Lets here some details!
james

turbo2256
09-19-2002, 12:43 PM
hope to get out this weekend lots of rain forcasted. On the up side I think you can install just the spacer and not the whole cap assy
so removal of upper mount and resealing is not necessary(unless you want to check it)... just pop the old spacer out pop the new one out switch it into the old cap and pop it into place make shue its seated properly not cocked screw body back to the cap remove clip check operation fill res. as necessary. If I had done the swap that way it would have save me about 2 hrs.

BigGrizzly
09-19-2002, 01:11 PM
NO, the spacer doesn't come out. It must be cut off and no more than 1 inch. What I did since I have two boats. I made a tool it slopped ocer the stop snd covered the threds. Then cut the stop off and beveled it like the stock stop with a combo in/out bevel tool(can be done with sand paper. The reason they send you the parts is so you don't make a mistake and hurt the threads or leave debree in the top. Besides the fact they are a great company to deal with and always have been. Mike explaned this to me when I called over a year ago.

Clayman the speed will increase will come only if your boat plows, or can't lift the bow enough to airiate. Handling imptoves for the same reasion. Remember you can always dropp the tabs to stop porposing ot too keep the hull wet. On the Criterion, at top speed the contact was minimal because the boats is lifted high and flat. The Corsican and the rocker hull is a different story, it gets real airy now. Lil Grizz picked up a couiple of MPH due to the fact its 22ZX with the step hull and was always to wet. In his case ride was really improved. Again all this came about because I tried to spend more money and Bennett just tried to save me some. My hats off to them! Whatis also funny I mentioned this in a post a year ago and no one paid any attention to it.

turbo2256
09-19-2002, 01:54 PM
Big Grizz,

Mine are on a 2001 boat so the newer ones might be different. The caps they gave me and the ones already on the boat snapped appart.

Tabman II
09-19-2002, 03:06 PM
Good Afternoon Gentlemen!

I see we are in the process of installing the new Reduced Height Upper Hinges, but there is a little confusion about just replacing the Spacer only.

Please, please, please replace the entire Upper Hinge not just the Spacer. The Spacer is chemically welded here at the plant, so snapping it out will not work. If your Spacers will come out like this, then please let me know so I can replace them. Using Upper Hinges that the Spacers will come out of will only cause trouble at a later date, since the Spacer will fall out and prevent the piston from operating correctly (I.E. blocking it down)!

If you need anything else, feel free to contact us.

MJ Thomas
Bennett Marine, Inc.
Client Services
trimtabs@earthlink.net

BigGrizzly
09-19-2002, 03:17 PM
Now this is real C.R. Tabman wants us to be safe and happy. He has made my day several times. Mike glad I called you a year ago! I forgot you said Chemically bonded. You saved me many dollars

Tabman II
09-21-2002, 11:05 AM
BigGrizzly,

You are very welcome! Anytime we can be of service to you, don't hesitate contact us.

In Your Service,
MJ Thomas
Bennett Marine, Inc.
Client Service
trimtabs@earthlink.net

turbo2256
09-25-2002, 12:21 PM
Thanks for that info Tabman thats what I was woundering about the old ones did come out quit easly and did not appear to be bonded in any way that I have encountered.

As for performance the boat does ride different seems smoother faster not shure yet. Basicly without indicators starboard tab ended fully up and port tab about the position it was before installing the shorter caps. As winter is creeping up on us here in Mich its likely boating is done for me this year.

Tabman II
09-25-2002, 03:38 PM
turbo2256,

Well, if you get a chance to try them out, please let me know your findings. If not, get back to me next season with any problem.

If you need anything else, just drop me a line!

Sincerely,
MJ Thomas
Bennett Marine, Inc.
Client Service
trimtabs@earthlink.net