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I am repowering with a new 90 HP E-Tec, replacing a 1984 60 HP Johnson twin. The old motor had 4 bolts through the transom into the splash well. The dealer says that the top bolt holes match up, but the bottom 2 do not. He is suggesting that they go through the transom underneath the splashwell.

Any suggestions or comments would be appreciated.

Thanks,

Patrick

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See this article on WhalerCentral.
http://www.whalercentral.com/articles...icle_id=82

Do not let him drill so the holes are underneath where you can't get to them.

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The 2 recent threads about engine mounting height by Jack Jordan and by zappaddles. Might contain some helpful information for you.

Zap

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Set it up so the lower two holes enter into the bottom of the splash well. The top 2 holes will be above these holes. You can then mount the motor as high as you like and you will still have access to the bolts and nuts in order to make removing the motor easy.

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This is such a common FAQ. Read the article Joe linked to. Follow Joe's advice NOT to let the installer drill below the splashwell.

In a nut shell, he should drill two new transom bolt holes that are 9-7/8" apart but only 6-1/2" below the existing upper holes, not 8" below likes he wants to.

When you tell him this and he objects, saying the motor will not be able to mounted all the way down on the transom, tell him YOU DO NOT WANT THE MOTOR ALL THE WAY DOWN ON THE TRANSOM. Yes, you should yell this at him.

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Thanks for the good advice.

Dumb question # 1: What is a AV plate?

I lived in Missouri for 9 years, so I am a little slow on the uptake.

Install the motor per Joe's diagram and that will raise the motor height.

Appreciate all your fellows help.

Excellen the rersponses that you get between midnight and 5 am on the west Coast.

Thanks to all of you

Patrick

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Patrick -- The AV plate is the anti-ventilation plate, also known as anti-cavitation plate or cavitation plate, for short.

For a propeller you should use the 13-7/8" x 17" BRP Viper or the 13-1/4" x 15" Stiletto Advantge 4.25.

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Dealer says it can't be done.
He says if you raise the engine 2 holes the bottom bolts still won't go into the splash well. He is leery of he motor boat running properly on the second hole.
Lots of negatives
Does anybody have a link to the mounting bracket of an E-Tech 90?
I agree strongly with you guys about drilling through the bottom of the splash well.

Help greatly appreciated

Patrick

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Your dealer is an idiot. He is trying to put the lower bolts through the second set of lower bolt holes when he should be putting them through the TOP SET of lower bolt holes.

This is precisely why I specified the vertical spacing be 6-1/2" not 8".

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Here is a photo of an E-TEC 90 mounted on a classic Montauk.

Note that this motor is not mounted "one hole up" (using the second bolt hole), it is not mounted "two holes up" (using the third bolt hole), it is mounted "three holes up" (using the fourth and lowest bolt hole), as high as the motor can possibly go.

The owner uses a 13-1/4" x 15" Stiletto Advantage 4.25 and reports no ventilation or blow out at all.

http://s4.photobucket.com/albums/y104...C_0081.jpg

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Thetis-

Print the article and this thread and bring it to the dealer.

There are more that 50 owners who have asked the same question, read the article and followed the advice and been totally happy.

Just tell the dealer, it's your money and you want it done per the article. Be polite but firm. Bring him the article.

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look at my personal page, my 90 etec is mounted 3 holes up and my bottom bolts are clearly in the splashwell.

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rfiglia -- Is your E-TEC 90 really as high as it can possibly be mounted?

What propeller do you use and how does it perform? Does it ventilate in turns?

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Tom I can go up 1 more hole, I should have said 2 holes up using the third hole, I am using a Stiletto 15 pitch

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OK, your E-TEC is mounted "Two Holes Up" using the third set of bolt holes.

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thetis - the advice you are getting here is correct, and you may need a new delaer!

Not long ago I help install an Evinrude V-4 on a 1965 Whaler 16' hull, which had the same transom bracket bolt hole design as the new Evinrudes. So that the lower bolts will come into the splashwell, the engine ended up about 1-1/2" high, which will give good perfromance with the proper SS prop.

It is easy to determine how high the mounting will be. Standard recomendations are for the centerline of the lower set of bolts to be 9-7/8" below the top of the transom. If the spashwell is not deep enouigh to accomodate this dimension, determine what dimension will work. Don't forget the larger diameter of the washers also. Subtract that from the 9-7/8" dimension, and you will have the effective hieght of the engine mounting. With the old 16' hull, the top holes will most likely be 6-1/2" centerline above the bottom set of holes. I would use large diameter fender washers on the top bolts on the inside. The engine installer will also have to take into consideration the curve in the Whaler transom when doing the drilling.

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OK, we have new information. Last night thetis emailed me a link to photos taken by the dealer that show the transom of this boat was cut down with a notch at some point in the past.

Photos of E-TEC 90 Sitting on the Chopped Transom

This is very, very unfortunate.

In the third photo of the four photos in the album there is a note from the dealer that states: THE HULL AND THIS PLATE NEED TO BE LINED UP.

I want to stop right here and point out that this is a classic error that long time dealers continue to make. The AV plate should be well above the bottom of the hull! Unfortunately it is going to be difficult to accomplish this now without rebuilding the transom, which is what really needs to happen.

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Short of rebuilding the transom, the only way I can see to make this work is to use the existing top holes in the transom and mount the E-TEC there using the BOTTOM most holes in the motor's mounting bracket.

Assuming the transom was notched to a depth of no more than 1 inch, this might work. It will result in the motor effectivly being in a not-quite "two holes up" mounting position relative to where the top of the transom used to be before it was cut down. The lower bolt holes in the transom will be 5-3/4" below the top bolt holes.

Using the VERY TOP OF THE LOWER BOLT SLOTS in the motor's mounting bracket should allow the lower bolts to clear the splashwell. The washers used there may need to be clipped or curved to fit the splashwell as described in this Boston Whaler Dealer Notice

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Tom,

Appreciate all your help.

Assuming that the transom was not notched, how far down from the top of the transom should the AV plate be?

Likewise how far up from the very bottom of the transom should the AV plate be?

Any pictures out there of an E Tech mounted on a classic that I could show my dealer.

Thanks

Patrick

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Patrick -- It doesn't matter how the AV plate relates to the top of the transom. The goal is the get the AV plate about ONE INCH ABOVE the bottom of the hull.

Some propellers will allow a much greater distance than that. The E-TEC 90 in the photo I liked to earlier has its AV plate about 1-3/4" to 2" above the bottom of the keel.

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Tom, can he use a bracket?

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What about a jackplate?

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It's a shame that someone cut the transom like that. As Tom pointed out the E-TEC can still be mounted CORRECTLY with that notched transom, using the top of the slots in the lower part of the bracket. No need for an extra piece such as a set-back bracket or jackplate. Get it mounted and enjoy, make sure you're proped right to see the correct rpm at wot.

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Looking at the photos more carefully, it seems appears the notch is more like 1-1/4" to 1-1/2" deep. This means it will not be possible to mount the motor as I have described. That is a real shame.

Yes, a bracket or jackplate could be used but you face the same problems as they use the same BIA standard bolt spacing too.

Sure you can drill new holes in a jackplate to adapt it, but if you are going to spend several hundred dollars and go to a fair amount of effort to adapt a jackplate to this transom, why not just fill the notch and be done with it instead?

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Tom,

Life is never simple, that must be why I enjoy it so much.

At this point I think my best bet is to bring the transom back to the original height, as you suggest.

This repair is beyond my comfort/experience level so I will have a shop do the repair.

I have the download on "locating fastening wood 16 1/2 Whalers.

How should the repair be done?

Suggestions and pitfalls.

Thanks for your help.

Patrick

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Patrick -- I am glad you intend to repair the boat properly. To fill the notch you first need to understand how the transom is constructed.

The transom of the 16'-7" Whaler is very simple. It is two layers of 3/4" Fir plywood laminated together and fiberglassed over when the hull was molded. The net thickness is about 2"

You should get an accurate measurement of how deep the notch is. It appears that if you drill the upper holes where they need to be i.e. 1-3/4" to 1-7/8" o.c. below the top of the restored transom, the bolt holes would be drilled through original transom, not through the filled in notch. This is good news if it is true.

The notch repair will then be much *less* structural than it would be if the upper bolts were to pass through the notch repair itself.

The fiberglass covering the cut that was ,made long ago needs to be removed and a wooden plug shaped to fill the notch. The notch should be cut and shaped to be tapered so that it will tend to jamb against the existing transom as force is applied aft. That is not a very good description but if you imagine the sides of the filler being sloped you can get the idea.

The only trouble with that is that it means you have to enlarge the cutout of the notch right where you are planing to drill those two new bolt holes and *if* it happens that they will go through the existing transom, I would not remove any more material there.

I would use two pieces of 3/4" plywood to for the filler piece and glue them together and to the transom with epoxy. Fiberglass would then have to cover that repair, feathered out into the surrounding area and then gel coated after the repair is fair.

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Progress,
I have my motor mounted on the boat. Good installation,

Goes in the water next week.

Did not have to do transom work.

I think that there was a repair done in the past.

The info that I need is the dimension of the transom from top to the bottom of the hull

Around 20 inches I would suspect, but I would like to know the exact.

Engine is mounted with the AV plate about 1 1/2 " above the keel.

Thanks,

Patrick

Will advise results of sea trial

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Patrick -- So how is the motor bolted to the transom? If the AV plate is about 1-1/2" above the keel, that sounds good.

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Tom,

The motor is installed with 4 bolts, the bottom are as far down as possible in the splash well. Washers are bent over like the Whaler service bulletin.

When the dealer was doing the install it looked as though the PO had notched the transom, however I examined the transom closely and I think that the "notch" might of been the original transom line and a repair or modification made to raise the rest of the transom a couple of inches. That is why I am requesting the orginal dimension from thr top of the transom to the keel or bottom of the "V".
\
Thanks

Patrick

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I see. The 16'-7" Whaler transom is a 20" transom. That is approximate and it is measured vertically, not along the slope of the transom.

Looking at your photos, it sure looks like it was notched. The factory joint between the inside and outside hulls skins was known as the "green line" and it was a point of pride at the factory to make that joint line visible and even, instead of covering it up with gel coat or trim moulding.

It was a way to prove and demonstrate the soundness of the joint. If the "green line" is not here, it has been worked on.

Do you have any photos that show the whole transom area in one frame? It will be obvious to us if the transom was raised or if it was notched.

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Tom,

I measured the transom fron the "notch" to the the bottom , the distance is about 20" as near as I can tell, as the motor is hung. The Original owner's son is comming up for the weekend and I will as him if he is aware of a repair.

If it was repaired or modified it was a good one. The transom is solid, and the original bolt holes showed no signs of any rot. When I get the boat out of the garage I will take some photos.

Thanks.

Patrick

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OK, going back to page one and looking at those four photos from your dealer, they do not show enough of the transom to be able to tell what is what

If it was built up instead of notched, that is good news for you.

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I was wondering how this problem was fairing ~ nice to hear it has a very good outcome! Enjoy, take two hats with you as you'll loose one! If any of the older 16' 7" Whaler owners can measure their cut out that was done at the factory, or even better yet, make a template and mail it to Thetis that would tell just what was done.

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Boat has been in the water for 3 weeks.

Very impressed with the ETEC.

Installation worked out, once it was installed "per owner's instructions"

AV plate approx 1 1/2 " above bottom of keel.

No porporsing or cavation.

2 adults, normal stores, 50 liters fuel, anchor etc.

13.25 x17 BRP aluminum prop.

Salt water, light chop GPS

2500 rpm 20 mph
3000 24
3500 34
5000 41

WOT 5150 RPM.

New to power trim, so still figuring out how to trim it out.

Boat motor better combo than 83 60 HP johnson.

Does not manauver quite as well at low spped, higher speed at in gear idle.

Question

Am going to purchase spare prop.

What performance changes will I get with a 13 1/4 x 15?

Thanks to all that contributed to make this a very successful installation, could not of done it without you.

Patrick

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Patrick,

I am glad to hear the new motor is performing well. You could raise the motor another bolt hole if you like, You would gain a little speed and lighten the steering effort.

If you want to upgrade your prop, go with the 13-1/4" x 15" Stiletto Advantage or Turbo 1. This will give RPM comparable to what you have now but with greater speed and improved grip and better acceleration.

If you merely buy a 15" BRP prop you will gain some RPM but may loose some speed. The optimal RPM range for the E-TEC 90 is 5000-5200 RPM.