Difficulty seperating powerhead from leg J60 1984

L

Lloyd

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Oct 14, 2003
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Hi,<br />I am struggling to seperate the powerhead from the leg on my 1984 Johnson 60 T&T.<br />I have stripped and reconditioned a few outboards before (Rally technician, boating enthusiast), but never had this kind of difficulty!<br />I have undone the 1/2" bolts around the outside and the 1/2" nut from the front centre, and all ancillarys / brackets, but she won't budge!<br />There is a sandwich plate in between the two and I guess this stays on the leg when you initialy seperate the 2?<br />I am hoping for some guidance before I get frustrated and crack the block :) , although I guess removing the gearbox and drive shaft to be the next thing to do?<br />Thanks from the UK,<br />Lloyd
 
G

G DANE

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Re: Difficulty seperating powerhead from leg J60 1984

Hi Lloyd, welcome aboard.<br /><br />Do you have a manual - if not, I strongly recommend you to get one, or maybe do some reading at you library. It is recommended to remove the lower unit first. Sometimes the driveshaft is stuck in the cranckshaft with rust, and you will need some tricks to loosen it up. But removing lower unit will tell you. Remember to release the shift rod under lower carb first. There is a bolt under the trim tab to remove too. Do this and post back with your results<br />Good luck !!
 
H

Hooty

Rear Admiral
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Oct 2, 2001
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4,496
Re: Difficulty seperating powerhead from leg J60 1984

Counting the bolt holding the trim tab, there are seven bolts to remove plus the shift linkage.<br /><br />c/6<br />Hooty
 
B

backdraft

Petty Officer 1st Class
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Dec 29, 2002
Messages
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Re: Difficulty seperating powerhead from leg J60 1984

lloyd, look for a bolt hidden up above the trim tab. nevjb
 
L

Lloyd

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Re: Difficulty seperating powerhead from leg J60 1984

Hi,<br />Thankyou so much for your helpful replys.<br />I do have a clymers manual, but it seems a bit vague when seperating, as opposed to stripping the powerhead, where there is much information!<br />Also I had undone and removed the gear lever quadrant below the 'inlet manifold'.<br />I think maybe I have missed the bolt under the trim tab (not really positive what a trim tab is!) though, I am assuming it will be up at the rear of the leg, buried? I shall see if I can find it today and post back,<br />Thanks again,<br />Lloyd
 
L

Lloyd

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Oct 14, 2003
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Re: Difficulty seperating powerhead from leg J60 1984

hi Again!<br />Realised after I posted what a trim tab is! Although I am curious what function it serves and how to adjust it? The clymer manual just says mark the original setting and refit as is. Which is fine if all the previous owners did the same :) <br /><br />Anyway, I digress. <br />Having removed all that holds the lower leg / gearbox on, the powerhead rocks with the loosened gearbox, - GREAT!<br />So the powerhead is fully loosened, but the main drive shaft is seized into the crankshaft :rolleyes: <br />Do you chaps have any handy hints how to overcome this hurdle?<br />I have tried forcing drifts into the small cavity between box and leg, but really dont want to damage the casing!<br />Thanks for all the help,<br />Lloyd
 
L

Lloyd

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Re: Difficulty seperating powerhead from leg J60 1984

Update :<br />I have been checking in the manual and it appears from the schematic, that the driveshaft won't clear the pump, ie. you need to remove the pump to slide it out of the gearbox. <br />Nightmare! On older models of this engine you could.<br />So my hopes of the woodruff key letting go at the pump and then the gearbox sliding off aren't going to happen! And I can't get enough clearance to undo the pump screws or cut the driveshaft.<br />Will stripping the gearbox internals in situ help at all? Although it appears from the diagram it won't.<br />I tried removing the inlet side crankcase in situ to gain access to the lower crankshaft splines, and therefore heat them, but can't get that off either! Must have bolts underneath I can't get to!!<br />Any help much appreciated!<br />Thankyou,<br />Lloyd
 
L

Lloyd

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Oct 14, 2003
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Re: Difficulty seperating powerhead from leg J60 1984

Well I managed to remove the inlet side crankcase in situ by chiseling off the 2 bolts hidden on the underside.<br />A lot of rusty water inside where it hasn't been used for around 10 years!<br />Took off the top main bearing to see if it was worth carrying on, and the crankshaft is sound, wipes clean thankfully.<br />Lots of access to the drive shaft / crankshaft connection now :) <br />As a starting point I have put a heater on it and am soaking it with rust penetrater.<br />If this doesn't work I will have to heat it more aggressively with oxy/acetylene, unless you know of any clever tricks I hadn't thought of?<br />Thanks for all your help,<br />Lloyd
 
G

G DANE

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Re: Difficulty seperating powerhead from leg J60 1984

Lloyd<br /><br />Do a search on this board for the words <br />"Screaming at lower unit" and you will find lots of good advise
 
G

G DANE

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Re: Difficulty seperating powerhead from leg J60 1984

Do the search in the Merc and Mariner Troubles/Repair forum, it was moved to there
 
L

Lloyd

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Oct 14, 2003
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Re: Difficulty seperating powerhead from leg J60 1984

I know what you mean, to get to where I am now has taken at least 6 hours!!<br />I renew the gearbox in a Subaru Imprezza in 10 minutes during a 'pit' stop, and it has taken 6 hours to pull apart a 2 stroke :rolleyes: , Much to the amusement of my colleagues!<br /><br />So would you normally resort to heating the crank or is there a better way?<br />I am a little apprehensive of heating it just in case it isn't the done thing!<br /><br />I thought I would journal this experience for others to either follow or avoid my mistakes!!<br />Thanks<br />Lloyd
 
L

Lloyd

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Oct 14, 2003
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Re: Difficulty seperating powerhead from leg J60 1984

Thought you were joking until the link was posted :rolleyes: <br /><br />G DANE = Genius!!!!!<br /><br />Qoute : <br />I had succes with this method once - if you are SURE the problem is drive shaft rusted to crankshaft: Open to max gap in the back.<br />Find two of some metal things same size as the gap at the middle or a bit in front of the middle. Squeze the two bits between lower unit and leg. Put the back or two back bolts in again ( you might have to find a longer bolt ) Then fasten 2-3 turns. Each turn will pull shaft out, or you will loose waterpump housing - which is a cheap way to get out.<br /><br />Will try it tomorrow and post the outcome!<br />Thankyou............
 
G

G DANE

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Re: Difficulty seperating powerhead from leg J60 1984

Another methos I used on a Chrysler i worked on, a very hard one:<br /><br />Take two pieces of wood, somewhat around 2" x 1 3/4 " x 2' . Here in DK used for roofs.<br /><br />Span them around motor leg, just above antiventilation plate with two clamps, real hard, so the wood bends in shape with motorleg. This will give you a possibility to hit it with a hammer without breaking the antiventilation plate or any fins. ( They dont take much hitting )<br />You will know when it sits firm enough to start prying.
 
L

Lloyd

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Oct 14, 2003
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Re: Difficulty seperating powerhead from leg J60 1984

The lower unit / leg / gearbox came off this morning, using G Dane's bolts technique + lots of soakings over 2 days with penetrating oil + 'shocking' the bottom of the crank with a punch + applying relatively low heat to the crank/shaft joint......THANKYOU!<br /><br />So, back to my original problem (!),<br />the block is still stuck fast to the leg / spacer plate.<br />I have managed to get a gap nearly all round though. Shall I continue forcing it or am I missing something? I assume the coolant pick up and exhaust bolt to the sandwhich plate, so this should stay on the leg?<br />Thankyou,<br />Lloyd
 
T

The Marine Doctor

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Re: Difficulty seperating powerhead from leg J60 1984

How are you trying to lift it off? Are you using the hook that is on the back near the head? Or are you trying to pull straigh off the center of the flywheel.<br /><br />You would have better success of the center of the flywheel.<br /><br />TMD
 
L

Lloyd

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Oct 14, 2003
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Re: Difficulty seperating powerhead from leg J60 1984

Let me explain :<br /><br />The powerhead is now stripped of pistons and all ancillarys, leaving just a bare block + crankshaft.<br /><br />The lower unit is removed leaving just a water pick up pipe and inner exhaust housing, both of which appear bolted up to the sandwhich plate.<br /><br />So I am trying to lift the block clear of the main casing/leg. I have 1/2" clearence all round except for the corner under the exhaust 'manifold' casing.<br /><br />I am levering upwards at this point and it is really tight, is there a possibility of any bolts holding it still?!<br /><br />Thankyou,<br />Lloyd
 
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