Yamaha outboard, snapped off bolt, lowerunit stuck.

[jeroen1978]

Tried to remove the lower-unit, what a disaster.

4 bolts at both sides came loose but de bolt underneath the anode snapped off.
Lower-unit seems to be stuck at this bolt probably due of aluminium oxide.

Here's a picture of the snapped bolt:

[url=https://postimg.org/image/ys5cyy28t/]

Tried to pry with a big screwdriver but at the front side of the lower-unit there's a very tiny gap, at the backside where the snapped off bolt is, it doesn't give a gap.

I've heated up the bolt with a solder heat gun, spraying penetrating oil while heating, no result.

I've smacked the lower-unit with a rubber hammer, without any result.

Tried to drill a hole into the center of the bolt but I couldn't, the propshaft is in the way so I can't drill into the center.

I want to try again the heat and freeze method.

Can somebody tell me which part I have to heat and which part I have to freeze?
Heat the bolt and freeze the aluminium around the bolt or heat the aluminium around the bolt and freeze the bolt?

And can somebody tell me how to loosen this lower-unit from the snapped off bolt?

I expect when the lower-unit is off the snapped bolt will come loose easily from the exhaust tower.

[TownsendsFJR1300]

Same thread / issue as this one?

http://www.yamahaoutboardparts.com/f...k-th28545.html

It'd be a bit easier to keep it on ONE thread..

I think you posted on the OTHER thread, you could NOT drill the head off due to space issues.

Do you have access to a small, AIR powered, grinder?

With a smaller, worn down cutting disc, you should be able to get in there and cut down the head. Obviously, be VERY CAREFUL around the aluminum LU, (perhaps tape some sheet metal to what you DON't want cut.)

I gather you don't have access to to TIG welder?

[rodbolt17]

corrosion has it.
most likely you will have to drill it at a horizontal plane and cut the bolt or use a thin hack saw and cut it by following the gearcase/midsection parting line.
not the first one I ever did.
I figure if 4 bolts wont hold it on a fith wont help.

[jeroen1978]

Yesterday I've been 10 years older in 1 day time but I've managed to get the lower-unit off.

We drilled out the snapped bolt and after some punches with a rubber hammer en prying with a flathead screwdriver the lower-unit came loose.

After that we could remove the snapped bolt with a plier (grip) so we can re-use the thread, see picture below.



Only a pity we didn't drill straight, now there's a small hole in the alunimium, see picture below.



For mounting the lower-unit it wouldn't matter, only I have to seal this hole because the water can reach the bolt directly so I must look how to close this hole.
Somebody has a good idea for that?
I've got a tube of gasketmaker for sealing parts which are in contact with water/coolant.

After prying with a prybar finally the powerhead came loose.
It seems that the plines at the drive-shaft have never been greased but they look clean like a whistle.



The big oilseal is indeed damaged, I hope that the crankshaft-bearing is not damaged to much.
The brown dirt at the cage of the bearing seems to be burnt oil, see photo below.



What's your experience when you see this bearing?
Is it good to put some grease into this bearing?
If yes, what kind of grease should I use?

Now I'm wondering what type of material the snapped bolt is.
It's a bolt M8 with a length of 90 mm (from the top of the head to bottom) and when you use a magnet pickup tool the bolt sticks to the magnet so it's no stainless steel.
Can somebody tell me what kind of bolt (material) this is?

In the servicemanual I read they use Yamaha Grease A.
Can somebody tell me what kind of grease this is and which grease I can use instead?
I want to lube oilseals, the crankshaft bearing, the plines at the driveshaft, the propshaft and al bolt against corrosion.

[FabricGATOR]

Quicksilver 2-4-C grease is what I commonly put on the spline and bolts upon reassembly when I don't have Yamalube grease A available.

When they recommend changing the water pump every year, it is really what they are saying is take apart the lower unit every year, clean and grease the bolts and spline. And while you are there doing that you may as well change the water pump...

[rodbolt17]

no grease on that bearing.
it is lubed by engine oil.
best bet would be to buy the bolt from Yamaha.

[TownsendsFJR1300]

For the newly made hole, I'd clean it spotless, make a "dam" inside. Then mix up some JD epoxy and fill in the hole. Let it sit 24 hours and your good.

For that bearing, CAREFULLY, check for ANY sideways play. Maybe use a screwdriver SAFELY UP AGAINST THE BLOCK-PROTECTED). There shouldn't be any play what so ever sideways... NOT even .005"

Also, IF you have a mid section bushing, use the correct Yamaha, mercury, etc grease. The correct Yamaha grease is not expensive at all. I used some marine wheel bearing grease on that bushing once, squeaked a month later-I was lucky enough to get a "do over"

You WON'T have the hassle pulling the LU using the correct grease if you R&R within a couple of years. Lil grease on the threads, splines, etc.. Goes together much easier too..



I had almost the exact same bearing (on a motorcycle) fail, TWICE, once with the cage actually coming apart... It did have a heavy electric rotor/flywheel on the end that I'm sure helped contribute to the failure:

The bearing on the crank, behind the balancer/cam shaft gear