a little help for a little outboard

dogfried

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hi all im new to the forum....i have just got my 1st outboard a 9.5hp johnson 1981!(well you have too start someware).it was siezed when i got it but i managed to unseize it by removing the head and lightly tapping the pistons untill they were nice and loose.however i noticed two of the head bolts (8 in total) were snapped.i ignored this i continued to start the motor in water.it runs but rough and blows white smoke like mad.it also fouls the water quite bad so i dont really want to take it out in this condition......any ideas?? mike:confused:
 

sarabande

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welcome dogfried

If some head bolts are snapped, then I am surprised you are managing to start it at all.


Probably what is happening is that the exhaust stroke is leaking through the head gasket,mixing with the cooling water and creating steam. As it's a 2 stroke (yes ?) this means that oily exhaust gas is being blown onto the surface of the water - not good !


It really does need fixing, and that means removing the broken studs (which may be corroded in - hence them being broken) and sorting out a new gasket too.


Is the impeller working OK (i.e. do you get a stream of warm water coming out somewhere when the engine is running ?)

best of luck.
 

VicS

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Things you should be checking with a motor that is new to you or has been idle for a time: Awakening a sleeping outboard
First thing will be to sort out the broken head bolts Id think and fit a new gasket.
A compression test would be sensible.

Are you sure its a 1981 9.5 ?

9.9 replaced the earlier 9.5 s in 1974. So if is a 9.5 is 1973 or earlier. If its a 1974 or later its a 9.9
Tell us the model number and we can identify it .

All you need to know about OMC 9.9 models

Some pictures in that link will show the differences between 9.5s and 9.9s.
 
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Lakesailor

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Possible that the head is already warped by running unevenly torqued down. May need skimming. Studs may not drill out well and the holes may need Helicoil inserts.
You are starting to look at possible costs here.
Are you absolutely certain there were 8 head bolts. This is the 7.5 hp and it looks the same as the 9.9 in Vic's link.
(The water jacket sideplate cover has 8 bolts according to Vic's link)

Jonhnsonblock.jpg

If it has the water tube grommet at the top of the leg it's worth replacing as they swell and block off the cooling water flow.On the 9.9 it's the water return grommet to the exhuast that deteriorates.
 
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VicS

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prompted by Lakesailors query about the number of head bolts I have looked a little further.

9.9hp engines had 6 bolts but 9.5hp engines did in fact have 8.

I guess then it is 9.5 but rather older than 1981. 1964-73 in fact.
 
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