Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Engine mounting height on old Whaler

Posted by Perry Vayo on 05/20/13 - 12:25 PM
#1

Hey all,

I'm gonna launch next weekend, and was planning to check the engine height. Currently the engine (1984 90 Evinrude) is mounted all the way in. The transom hookes are sitting on the transom.

When looking it over, I noticed that the bottom bolts were never installed - looking at the inside of the the hull I guess there is no way to do it. So, I'm wondering is it's okay to raise the engine on just the two top bolts? Should some sort of spacer be used on top of the transom to give the hooks someplace to rest?

Or, is it okay to just have the two top bolts taking all the weight? Is there a way to install the bottoms?

Is it normal to install on a Whaler with only the two top bolts? That doesn't sit well with me.

Thanks.

Posted by Joe Kriz on 05/20/13 - 12:28 PM
#2

Perry,

We have an article on that and many discussions.

Here is the article:
http://www.whalercentral.com/articles...icle_id=82

Posted by Perry Vayo on 05/20/13 - 1:47 PM
#3

Graciias. I looked, I just didn't find.

Posted by Joe Kriz on 05/20/13 - 2:32 PM
#4

Perry,

I would drill the bottom Green holes and mount the motor 2 holes up.
No need for a block or spacer under the motor bracket and the transom.

This is also assuming your top holes are already 1 7/8" to 2" from the top of the transom.

Posted by contender250 on 05/20/13 - 6:02 PM
#5

That engine should have two blind holes, that are to be at the bottom of the inside transom, Go to a local OMC dealer and ask to borrow the template for this setup, (if they do not want to loan it out take a thin piece of cardboard and copy it) then you can drill them out in the right place. e you engine)(going to need to remove the engine) The blind holes on the engine mounts are use mostly on whalers because of their hull design on the transom. I have this setup on my Whaler (1975 hull with a 1985 Evinrude) and the engine sits right on the transom...

Posted by Joe Kriz on 05/20/13 - 6:08 PM
#6

Nobody wants that anymore.

You would forever be stuck with your motor all the way down which isn't the best.

Advice from everyone here is to drill the holes in the transom so you can always install a motor with the Standard bolt hole pattern.

Absolutely forget about mounting any motor using the blind holes.
That is old technology and nobody mounts a motor that way these days.

Posted by Perry Vayo on 05/20/13 - 7:35 PM
#7

Yes, my intent is to raise it up a hole or two. I'll take a look over the stern when we are on the water to see how deep the AV plate is.

Drilling the "green" holes would still allow a repower later using the same holes?

Just wondering.

Thanks.

Posted by Perry Vayo on 05/20/13 - 7:44 PM
#8

Joe Kriz wrote:
Perry,

I would drill the bottom Green holes and mount the motor 2 holes up.
No need for a block or spacer under the motor bracket and the transom.

This is also assuming your top holes are already 1 7/8" to 2" from the top of the transom.


Would drilling the green holes require drilling at an angle to hit the splash well, as I've read here and elsewhere?

Posted by Joe Kriz on 05/20/13 - 9:11 PM
#9

Perry,

Yes, drilling the Green holes will allow anyone to repower using any motor without drilling any other holes in the future.

You would not need to drill at an angle for the Green holes.
Perpendicular to the transom as normal.

Posted by Perry Vayo on 05/21/13 - 4:41 AM
#10

Okay. thanks again.
For the amount of messing around needed to mount an engine correctly on older whalers I cant believe that no one has made an adapter to do the job! Wish i had a machine shop!

Posted by Perry Vayo on 05/21/13 - 4:46 AM
#11

One more thing

Do you guys feel that it would be too unsafe to lift the motor to tahe third hole and test the result with just the top bolts in place?

Posted by tedious on 05/21/13 - 4:53 AM
#12

Perry Vayo wrote:
One more thing

Do you guys feel that it would be too unsafe to lift the motor to tahe third hole and test the result with just the top bolts in place?


Yes, it would be unsafe - you'd possibly damage the transom and lose the motor in the process. Don't do it.

Tim

Posted by Perry Vayo on 05/21/13 - 10:54 AM
#13

tedious wrote:
Perry Vayo wrote:
One more thing

Do you guys feel that it would be too unsafe to lift the motor to tahe third hole and test the result with just the top bolts in place?


Yes, it would be unsafe - you'd possibly damage the transom and lose the motor in the process. Don't do it.

Tim


Message received. It's what I was thinking myself, but just wanted to make sure. Thanks.

Posted by contender250 on 05/21/13 - 2:06 PM
#14

Joe The old technology is what is required for the engine in question (1984 OMC) this is how it should be mounted, Perry has also stated that he has two holes already drilled (two top holes I think) in the transom. If he wants to mount or raise his engine he will have to drill some more holes. Perry I would look into a manual alum. set back by say CMC, This setback with match the holes you have, but you will need to drill two more. The setback will only work with teleflex type steering. Mounting the setback with give you the opportunity to change the height of the engine without drilling different holes. Just another way to skin the cat....

Posted by Joe Kriz on 05/21/13 - 2:11 PM
#15

No, absolutely NOT.
He should drill the Green holes and then he could mount any new or older motor.

Mount it using the Standard BIA pattern as mounting the motor all the way down is no longer done.

Setback brackets to me are ugly.
Only use a bracket if you actually have a need for one.
Even if he chooses to use a bracket, drill the GREEN holes and then mount the bracket.

Every member here, out of 28,000, wanted to raise their motor up, NOT lower it down.

Posted by Perry Vayo on 05/21/13 - 7:58 PM
#16

To me the set back would be the last resort.

I have read on other forums about drilling the green hole at six inches down from the top holes as a mounting work around. I think i actually saw it in a Whaler publication. That gets all the bolts into the well and no need for a plate.

The only dowmnside i see is not really being able to test the various hole before commiting.

Posted by Joe Kriz on 05/21/13 - 9:30 PM
#17

The Green holes are 6 1/2" down.

This allows you to raise the motor one hole if you need or want to go up another hole.
There is no reason to go down.

Posted by dgoodhue on 05/22/13 - 9:48 AM
#18

I agree no classic whaler engine should be mounted with blind holes. It's bad enough many new whaler dealers mounted the motors in the 80's with blind holes and at the wrong engine height (and didn't follow boston whalers advice.).

Posted by contender250 on 05/22/13 - 11:01 AM
#19

I have a 1975 hull, with a 1985 140 looper on the transom. The engine was mounted using the blind holes, and has been that way since I mounted the engine in 1985. The cavitation plate is one inch above the bottom of the hull while the engine is in a vertical position (at the correct height) and the engine sits on the transom as well...To each their own...

Posted by Perry Vayo on 05/22/13 - 6:30 PM
#20

contender250 wrote:
I have a 1975 hull, with a 1985 140 looper on the transom. The engine was mounted using the blind holes, and has been that way since I mounted the engine in 1985. The cavitation plate is one inch above the bottom of the hull while the engine is in a vertical position (at the correct height) and the engine sits on the transom as well...To each their own...


Sure, that's fine. I'm sure it runs great with that set up. Mine does as well. I think the point is, lifting the engine a bit can help with efficiency and performance. So, with the price of marine fuel, it may be worth doing. That's why I'm thinking about it. I will be checking the AV plate with the boat on the water over the weekend and will then decide what to do about it.

Perry

Posted by Joe Kriz on 05/23/13 - 4:15 PM
#21

contender setup his motor almost 30 years ago.
The engine was mounted using the blind holes, and has been that way since I mounted the engine in 1985.

That is old school using the blind holes as the motor cannot be adjusted up or down using that old method.
That method is no longer used.
All motors since the late 70's uses the Standard BIA mounting hole pattern.

Here is how a motor should be setup for the correct height.
http://www.veradoclub.com/smf/index.p...opic=137.0

Perry,
Layout the Green holes (mark them with pencil) 6 1/2 inches from the top hole on your transom. See where they fall on the inside of the transom.

Where are your top holes?
1 7/8" or 2" down from the top of the transom?

Also measure and layout the 7 1/4" Yellow holes. See where they fall on the inside of the transom.
http://www.whalercentral.com/articles...icle_id=82

Let us know if it is possible to drill the Yellow holes.

Posted by Tom W Clark on 05/23/13 - 9:18 PM
#22

I have a 1975 hull, with a 1985 140 looper on the transom. The engine was mounted using the blind holes...The cavitation plate is one inch above the bottom of the hull while the engine is in a vertical position (at the correct height) and the engine sits on the transom as well.


No, the anti-ventilation (cavitation) plate is about one inch below the bottom of the hull.