Stuck Powerhead

[Boatnut]

First the facts,
1988 yamaha 90 hp 2str. 3cyl (salty ) 20" mid
Worn pivot bushes, need to mount steering arms, Powerhead to come off!
10 bolts out plus two long bolts thru adaptor broken, just below bolt head

Now the speculation,
I seem to recall the manual listing 13 bolts, am I missing one?
There is a vertical bolt into the powerhead at the front, under the reed block and directly above the top engine mount casting. It does not look like it secures the adaptor to the powerhead unless it is part of some sort of mounting bracket. It looks more like part of a housing that holds a bearing for the crankshaft. I have parts list and exploded diagrams but does not detail adaptor plate.

I havn't heaved off it yet until i am sure that the bolt i refer to does not secure the powerhead. i expect the gasket to be well and truly stuck

i could use a little advice on the best way to 'unstuck' the gasket when i'm sure i've got all the bolts out.

I can just imagine the eyes of some of you, rolling while your thinking, what's this idiot up to , but go ahead and give it to me. the good, the bad and the ugly

[fyremanbill]

I've had good luck putting them in tension with a hoist or come-along, then hit it with a hammer. They usually pop right off. Hill gave me one that was so badly stuck, I had to use the "Jaws of Life" to separate it.

[whaledog]

I started my outboard career in a salty enviroment.Merc power heads would have drive shafts rusted in the crankshaft.I would have to cut the shafts to remove power head.

[Fast Fred]

lookin at the book, cuzz ain't seen a 90 for a while, 4 up front, the main 6 bolts,
and one more under the head. no hammers, just give it a pry in the right spots,
she has lineup pins. easyer with the lower off. a lite pry to brake the seal and then up.

[Skoontz]

Years ago, I bought a 20 ton hydraulic puller for removing planterary drive gears from our D-8 tractors. Later years, after Cat changed that drive it was no longer needed, so I rigged a strap for behind power heads, installed a pressure guage, and, with a little heat on the bad ones, and a little constant pressure from the puller, and, lots of PB-7 blaster, it unstickifies stuck motors with ease and no damage.

[Master Oil Racing Team]

My first year of racing I had no clue to mechanic work. I got a KG7 that was stuck that I thought I could overhaul. Everything was pretty much locked up and took some work to get parts off. When it came to the crank, I couldn't make it budge so I got a puller on it. I was just starting my junior year in high school. The first thing I did when I got home from school was pound a few times on the puller and take up more slack. I had it about as tight as I could get it without breaking part of the crankcase. This went on for close to a month. I was just about to give up when one day I came home from school and whacked the puller. The crankshaft fell out. It was then I noticed a bolt that held the reed cage in place. Seems like it was about 3/8ths, but I managed to shear that anchor bolt without tearing up the crankcase.

[Boatnut]

Thanks for the replies. My appologies for not responding sooner (been busy as a one legged man in an *** kicking contest the past few days)

Got the Lower unit off without any trouble.

Two of the long main bolts broke just below the hex head so i have dropped the mid section to expose the ends of the bolts. I can now get to them to weld a nut on the end and have another crack at getting them undone.

I like the tension idea but the hammer is staying in the toolbox

might have to look a bit closer, got the six main bolts (2 broke) and the one under the head but have only found 2 up front.

On a side note, i been doing some reading about dry stacking, seems like it would be a good idea to to do it while i've got it apart and save pulling it apart again later. i understand the plumbing but do i remove the muffler (not the tuner) and leave it under the bench?

Gota love boats . Thanks again for the replies . i will try and post some pics in the next few days, not much to look at yet, just a dusty boat and motor bits all over the shed.

[Boatnut]

Powerhead IS OFF Thanks for the help
the next thing i need to work out is what to do about solid mounts. It's pretty hard to find anyone here in oz that knows anything about them and even harder to find anyone that can supply them. I believe i can machine what i need but the main question is what material to make them from?
Has anyone used Urethane or UHMPE? while they are not as rigid as alum. i reckon it would be a suitable material. I am keen to hear anybodies thoughts and experiences.
again thanks for the help

[j nye]

yes boatnut check out this web site www. hydrotecmarine.com they have your solid motor mounts . i ordered a set for my 50hp yamaha and i wish i would have made them they were just alum solid milled the same shape as the factory ones but tey did the job that bad boy dont shake around no more hope this helps

[Boatnut]

Thanks for the reply, checked out the site, good stuff there. Problem is getting stuff here in a timely fashion. Was easier to make them mounts, just cost a few hours.
waitin on a few trinkets to finnish rigging. should be water testing in the next couple of weeks.