Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Raising motor on transom

Posted by mtown on 07/23/13 - 10:28 AM
#1

I am finally about to raise the 90 hp 2 stroke Yamaha on the 1966 16/17. It is currently mounted all the way down and I am planning to move it to the third or fourth hole. I seem to recall reading an article where someone used the trailer tongue jack to raise their motor but can't find that thread. Does anyone have any suggestions for supporting the motor during this process.

Posted by Phil T on 07/23/13 - 11:06 AM
#2

Assuming the bottom bolts are not using the blind holes and are in the slots.

You need a helper to steady the motor.

Make sure you have enough height on the tongue jack travel. If not, place blocks under wheel to gain sufficient height.

Block the trailer wheels.
Tilt the engine down.
Raise the tongue till the skeg is touching the ground.
Loosen the lower bolts in the slots
Loosen and remove the upper bolts. (Have friend steady motor)
Raise the tongue to appropriate height to
reinsert upper bolts in correct holes with fresh sealant.

Edited by Phil T on 07/23/13 - 5:01 PM

Posted by wing15601 on 07/23/13 - 11:10 AM
#3

Put a piece of lumber beneath the skeg to protect it from damage on the ground.

Posted by mtown on 07/23/13 - 1:54 PM
#4

Thanks guys. I am using the blind bolts. I have extracted one and loosened the other to assure they were not "welded" to the aluminum of the motor. I feel like it will be very hard to use the slots for the bottom holes and be high enough in the splash well, so I was considering drilling new holes to re-bolt into the tapped inserts that are used now.[blind holes] The top holes will be re-used just in different motor holes. Phil, I guess the helper just leans against the motor to keep it against the transom and that is about all that is needed.

Posted by freeportd on 07/23/13 - 4:09 PM
#5

Phil,

Once the bolts are out (top) and loosened (bottom), wouldn't you want to raise the tongue to align the engine with a different mounting hole? I would think lowering the tongue would lift the engine.

Posted by Finnegan on 07/23/13 - 4:34 PM
#6

You can't raise the engine this way, as Phil indicated, since your engine is blind hole mounted.
You will have to completely remove the engine from the boat to do a proper job.

I have mounted an engine with the modern B.I.A. bolt pattern on a hull like yours. To bring the bottom set of bolts into the splash well, the engine will HAVE to be mounted 1-1/2" high at minimum, maybe a touch more. That is all the height you will want or can use with a 42 MPH rig. You will need a Stiletto prop, since they are made in relatively low ptiches.

With the engine off, you will first have to fill the blind holes, with method of your choice. You may also have to fill the top holes also, depending on how high you want the engine. Then you will have to drill new holes from a BIA template, (or full size drawing you can make up). The deciding placement will be determined by the BOTTOM set of holes so that the bolts come into the splashwell and can receive the washers/locknutsnuts. Let the top holes fall where they may. Top bolts go in from the inside, nuts on the outside. A transom bolt plate is advised on the inside top bolts, about $25., since you may be closer to the top than the recommended 1-7/8".

There is an excellent B.I.A. bolt pattern drawing on this site for reference. In your case, the vertical spacing of the bolts will have to be changed from the standard 8" to 6-1/2".

Posted by mtown on 07/24/13 - 5:24 AM
#7

I have studied the template on the site and the main reason I am contemplating the blind install again is that it would allow me to re-use the top holes and would simply mean re-drilling the lower holes about 1 1/2" higher than they are now. Thanks for the input.

Posted by Tom W Clark on 07/24/13 - 6:35 AM
#8

...the main reason I am contemplating the blind install again is that it would allow me to re-use the top holes and would simply mean re-drilling the lower holes about 1 1/2" higher than they are now.


If you drill new "blind holes", you will not be able to repower with a new motor in the future without drilling yet another set of holes.

If you drill new lower holes on the BIA standard lateral spacing, you can mount your current motor higher now, reuse you existing upper holes and be able to bolt any other motor on the boat in the future.

Same amount of effort, many more options.

http://www.whalercentral.com/articles...icle_id=82

You want to drill the green holes.

Posted by dauntless-n-miami on 07/24/13 - 7:52 AM
#9

mtown, there may be one more option.

You could consider a manual jack plate with the least amount of set-back for your setup.

At worst, you could make a template of your existing bolt hole arrangement from your transom and redrill the transom face of the jack plate.

You can leave your transom unmolested and possibly give your outboard more range of height adjustment.

Just my "2 cents"...

Angel M.

Posted by mtown on 07/24/13 - 9:56 AM
#10

Thanks to everyone for the tips. Mission accomplished. I used a rope to create a sling that went up into the pinch point of the motor and motor mount. That was hung from a temporary beam supported by a step ladder and a cross beam of my carport. I then used a regular auto shop jack and a piece of wood to put upward pressure on the motor at the motor mount. Removed blind bolts completely and then gingerly backed out top bolts one at a time. The motor shifted when I removed the starboard top bolt and aligned with hole #2 on that side. I re-inserted as a temporary hold and the shifted the upward pressure slightly to port side of motor mount. Removed top port side bolt and got to hole #3 and re-inserted bolt. Then same procedure to get starboard to hole #3. The rope did its job as a safety harness only allowing slight movement that could be controlled with the jack or by lifting manually. Had no one around to help and never had an oh s$%#@ moment. Bolted up tight after putting tape over stern side of blind holes. Used epoxy resin and saline bottle to fill old holes after tilting trailer way up in front. Tape will prevent epoxy from attaching itself to motor mount. To drill the green holes at Tom's recommendation I drilled from stern toward splash well and angled more steeply than the transom angle, and have just enough room for the washer on the splash well side. If you are drilling at the same angle as the transom you will definitely have to go to the 4 th hole up. I have only run this boat once since purchase but am interested to see how this works out. I have almost identical [1964 with a 70 hp 2-stroke Yamaha] and I plan to do the same to it next winter.

Posted by mtown on 07/21/15 - 9:05 AM
#11

Just searched and found my old thread about raising 90 hp Yamaha. Figured that by posting it would help others find it.