Dropping lower unit

[ollyit]

Evinrude 1989 70hp
Be70elcca

Just forked out on new genuine impellor as I dont knowwhen it was last done + the tell tale seems a touch weak unless I bung a muff on with a hose attached to it - I've undone all the bolts I can find on the leg itself inc under the trim tab and all the anodes - I've got the clymer 48-225hp manual and been through it very closly and theres no mention of anything else - research on the net suggests theres a shift rod also - when disconnecting the shift rod should there be any other reason for the leg not dropping very reluctant to hit leg the with anything - images attached showing area where the shift rod mech resides, a bizarre mechanism took me ages whilst panicking I may have broken something relinking it up - must be a knack! - Many thanks in advance,

Shall I just give it a whack with a rubber hammer in a few places?

[ollyit]

also as I've been ar*ing about with it - does anyone know which way the lever needs to be should it need to be in a Forward or Reverse gear for the leg to detach from the mid section

my clymer manual is actually rubbish apart from the wiring diagrams - an impellor change has got to be up there with one of the most common routine maintainence jobs

[Chris]

Olly,

I think if the set up is anything like my old Johnson...

There would be a shift Rod that travels down the leg to the gearbox. This needs to be disconnected at the top end.
That shift lever that you have disconnected will go across under the engine and then connect to the rod.
There will be a way of disconnecting the rod from the shift lever but don't expect it to be that easy.

[ollyit]

right ive unlocked the the rod and it still wont drop - it was a split pin arrangement then the lever can be pulled towards the starboard side - this unhooked from the downward shift rod -

I dont suppose the drive shaft splines are being stubborn are they? is this common?

thanks chris

[ollyit]

Originally Posted by Chris

Olly,

I think if the set up is anything like my old Johnson...

There would be a shift Rod that travels down the leg to the gearbox. This needs to be disconnected at the top end.
That shift lever that you have disconnected will go across under the engine and then connect to the rod.
There will be a way of disconnecting the rod from the shift lever but don't expect it to be that easy.

thanks chris - did it have to be in a certain gear do you recall for the lower unit to fall? - I've run out of s*dding daylight now!

[Nos4r2]

Originally Posted by ollyit

thanks chris - did it have to be in a certain gear do you recall for the lower unit to fall? - I've run out of s*dding daylight now!

No. Your driveshaft is stuck. Don't start hitting it-it won't do any good but you'll probably break the anti-vent plate and it still won't move.

Give me a bell if you're in the sh*t.

[Nasher]

Olly

As Nos says, don't start hitting it, you will break the cast plate.

I seem to remember a bolt being hidden under the trim tab on my old Johnson. might be worth a look.

It could be however that the splines are stuck in the crankshaft. The only way I ever resolved this problem was on an old 35HP Chrysler.
I got the engine good and hot before trying to remove the bottom end, but on that engine I was also able to point a cold hose directly at the shaft through an exhaust port. Cooling the shaft and heating the crank sorted it.

It could also be corrosion around the stainless dowels between the castings, which can sometimes be loosened off with a gentle tapping on the side of the casting, but I stress gentle tapping with a soft mallet.

Bring it up the church Monday night and we'll all have a go

Nasher.

[Chris]

Olly

Do you have any loosening of the gearbox yet or is it still locked solid?

If its still solid then as Nasher suggested check the bolt that is under the trim tab, its a common one to forget as you can only see it once you have removed the tab

If its now loosened then it sounds like the crank as suggested. I cant really offer any advice other than some sort of splitter.

[ollyit]

Originally Posted by Nasher

Olly

As Nos says, don't start hitting it, you will break the cast plate.

I seem to remember a bolt being hidden under the trim tab on my old Johnson. might be worth a look.

It could be however that the splines are stuck in the crankshaft. The only way I ever resolved this problem was on an old 35HP Chrysler.
I got the engine good and hot before trying to remove the bottom end, but on that engine I was also able to point a cold hose directly at the shaft through an exhaust port. Cooling the shaft and heating the crank sorted it.

It could also be corrosion around the stainless dowels between the castings, which can sometimes be loosened off with a gentle tapping on the side of the casting, but I stress gentle tapping with a soft mallet.

Bring it up the church Monday night and we'll all have a go

Nasher.

thanks nash - well worth a shot - I'll run it up tonight and see what gives

[ollyit]

Originally Posted by Chris

Olly

Do you have any loosening of the gearbox yet or is it still locked solid?

If its still solid then as Nasher suggested check the bolt that is under the trim tab, its a common one to forget as you can only see it once you have removed the tab

If its now loosened then it sounds like the crank as suggested. I cant really offer any advice other than some sort of splitter.

Chris,

I have a very slight left and right movement a tiny gap probably 1mm at the front section near the prop end - yes I've definetely removed the hidden hex bolt under the trim tab - thanks matey - I'm going to try nashers plan of attack first -

Olly

[doggypaddle]

Had a really stubborn Merc 6 cyl once, the only way we could get that apart was by using a hole saw on the leg halfway up to gain access to the shaft, then chop it through with the gas axe. This allowed it to be stripped without damage to the casings. the intention was to get a local bloke who specialised in shortening halfshafts to weld it back together, but unfortunately when we eventually slide hammered the end out of the crank there were no splines on the crank or shaft, and the engine was scrapped. shame it was a nice early one too. a bit of grease every season can save a lot of hassle.

[Nasher]

Originally Posted by ollyit

Chris,

I have a very slight left and right movement a tiny gap probably 1mm at the front section near the prop end
Olly

Olly
Unfortunately that does sound like a classic splines stuck in the crank situation. - Sorry.
You don't really have many options apart from warming the engine up and cooling it down a few times. As the engine hasn't been run in a few years this may release it if its not too bad. It could help to get the engine in a wheely bin as deep as possible to flood the exhaust chamber with water to cool the shaft.

Some absolute last resorts:-
-Source another bottom end and destroy the old one getting it off to gain better access to the drive shaft.

-Strip the powerhead in situ, splitting the crankcases from around the crank and hope you can get it off on its own.

-Turn the engine upside-down and fill the exhaust with diesel, some of which may find its way to the join and loosen it off. Although you'll also fill the cooling system and crankcase with diesel via the exhaust ports.

-Ebay the engine.

Nasher.

[doggypaddle]

Originally Posted by Nasher

Olly
Unfortunately that does sound like a classic splines stuck in the crank situation. - Sorry.
You don't really have many options apart from warming the engine up and cooling it down a few times. As the engine hasn't been run in a few years this may release it if its not too bad. It could help to get the engine in a wheely bin as deep as possible to flood the exhaust chamber with water to cool the shaft.

Some absolute last resorts:-
-Source another bottom end and destroy the old one getting it off to gain better access to the drive shaft.

-Strip the powerhead in situ, splitting the crankcases from around the crank and hope you can get it off on its own.

-Turn the engine upside-down and fill the exhaust with diesel, some of which may find its way to the join and loosen it off. Although you'll also fill the cooling system and crankcase with diesel via the exhaust ports.

-Ebay the engine.

Nasher.

And the hole saw throug the leg trick....never fails, you may need a new driveshaft or a halfshaft welder though .......
1" holesaw will go through in seconds then cut the drive shaft through with a hacksaw blade.
the shafts weld really well, i shortened a few early evinrude twins like that

[ollyit]

Thanks guys - appreciate your help

[Nasher]

Come on Olly............How you coming along with getting that bottom unit off?

Nasher.