removing heads, how too

grub_ba76

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Jan 9, 2009
Messages
25
hi, im just wondering is there a speacial way the heads should be un done?
i know putting them back on theres a sequence and torque to bolt back up.
ive purchased a manual but wont be here for a week and would like to get started so its ready for when i get parts and manual..
if there is a speacisl way can somone explain the right way to remove bolts.
jhonson 90hp, 94 model
thanks heaps graham
 

Joe Reeves

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Feb 24, 2002
Messages
13,262
Re: removing heads, how too

No special way to remove the cylinder heads.... pretty much straight forward. Take some picures and make a few notes as to what wires go where if you need to disconnect any. Why are you removing them anyway?
 

boobie

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Nov 5, 2009
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20,826
Re: removing heads, how too

Just out of old habit, I always start at the outside and work my way toward the center when removing. Just the opposite of installing.
 

grub_ba76

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Jan 9, 2009
Messages
25
Re: removing heads, how too

ok thanks, im having over heat problems and ive done thermo kit,pump kit,removed exhaust housing to check for leaks,removed power head to check for blocking and water pipe and its still over heating...water flows easy thru pipes and heads..recheck and recheck thermos....when hot i cant put my hand on either cylinder and alarm goes off over 3000 rpms.
people on here sugested i replace head gaskets and water deflecters...this is the only thing left to do that i can think of.
the motor starts and runs real good..
any other sugestions that any one can come up with?
thanks graham
 

boobie

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Nov 5, 2009
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20,826
Re: removing heads, how too

If the water deflecters are swollen that is most likely the cause of your over heat problem.
 

Joe Reeves

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Feb 24, 2002
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13,262
Re: removing heads, how too

(Water Deflectors)
(J. Reeves)

Water deflectors are actually lengths of 3/8" outside diameter rubber hose, installed between the top cylinder and any cylinder beneath it, and also between the bottom cylinder and the block. The purpose of the deflectors is to have the water follow a definite path around the cylinder walls. Unfortunately the deflectors between the cylinders will at times swell sideways due to either a previous bad overheating problem, or simply due to age and salt corrosion. This causes a water flow restriction which usually allows the water to cool sufficently at low rpms but not at the higher rpms.

This hose material can be purchased reasonably at any automotive parts type store if you care to make your own, or you can purchase individual deflectors at any Evinrude/Johnson dealership at a somewhat higher cost.

Removing and installing them can be a hassle at times, but not always. I use a sharply pointed scribe with about 1/4" of the tip bent at a right angle whereas I can reach in, jab the tip sideways into the rubber, then yank it out. It's necessary to clean the seating surfaces where the ruber contacts the block with a small rat tail file to eliminate salt deposits etc. When installing the new rubber deflector, coat the deflector and the metal surfaces with WD40 which will act as lubrication to allow it to go in as easily as possible.

Make sure that you insert something into that deflector area before cutting and installing the deflectors if you make your own so that you will be certain that they are the right length and also that they will be seated properly. Usually a very small amount will be left extending about the block sealing area..... simply cut the excess off with a single edge razor blade.
 

grub_ba76

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Joined
Jan 9, 2009
Messages
25
Re: removing heads, how too

yep i think u are spot on..just pulled one head of and its a mess. the water deflector is corroded in there and its badly blocked under the cylinders next to water deflecters on upper and lower cylinder. theres no way water was going aroung the cylinders or even getting near the deflectors...its like somone half filled it with rock salt lol...somone on here said to check deflectoers first up but i thought its flowing good. i was wrong and j reeves just explained it.atleast every thing is new, it just makes it more reliable
so that definatly my problem hey from what use are all saying..
thanks everyone and J. Reeves for the info and explaining it to me. use make it so much eaiser.
 
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