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Old 13 April 2010, 15:35   #1
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Powerhead removal

Hi All
Any tips on removing a powerhead on my Mariner 50hp 4 stroke as i need to get it off to replace the water grommet on the adaptor plate ( see my other thread 'Outboard cooling' )

my workshop manual makes it look very easy :

1. Drain engine oil
2. Remove lower cowlings
3. Disconnect a few bits and bobs- Fuel line, throttle and gear cables, battery leads ect
4. Undo 5 bolts either side and powerhead will lift off.

All seems too easy to me......

A big question is would i be better removing the lower unit first so the driveshaft and gear shifter rod are out the way?


Thanks
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Old 13 April 2010, 16:06   #2
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Quote:
Originally Posted by Dobieman View Post
Hi All
Any tips on removing a powerhead on my Mariner 50hp 4 stroke as i need to get it off to replace the water grommet on the adaptor plate ( see my other thread 'Outboard cooling' )

my workshop manual makes it look very easy :

1. Drain engine oil
2. Remove lower cowlings
3. Disconnect a few bits and bobs- Fuel line, throttle and gear cables, battery leads ect
4. Undo 5 bolts either side and powerhead will lift off.

All seems too easy to me......
It's not difficult with the right tools.
Quote:
Originally Posted by Dobieman View Post
A big question is would i be better removing the lower unit first so the driveshaft and gear shifter rod are out the way?


Thanks

Yes-it makes it far easier getting the powerhead off but don't forget to put the shift rod back in before you put the powerhead back on...
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Old 14 April 2010, 13:58   #3
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powerhead

Yip It does seem all easy . After pulling the powerhead you then have to pull the adaptor palte off . you have to do this by removing the top mount's and the bottom mounts to pull the midsection off . the midsection HAS TO COME OFF ASWELL . This is not a 5 minute job trust me . Water tube has to come out , better with gearbox off . The adaptor plate lifts up and then you can access the grommet . did you see my photos in last thread
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Old 17 April 2010, 16:15   #4
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I removed and checked the thermostat today and it's ok so the only thing left is the grommet.

I'm pulling the powerhead off tomorrow to inspect it, really hope it is the problem as i can then take steps to fix it.

I'll try to take a few photo's and report my progress...
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Old 17 April 2010, 17:32   #5
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Good luck , have fun doing it . It is the GROMMET
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Old 18 April 2010, 10:49   #6
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Outboardtech - you are spot on, it is the grommet....
The water tube itself is fu=ine and so is the adapter plate, just need a new grommet and the 2 gaskets and she'll be as good as new.
i did not take off the top mounts to get the mid section off, just the lower ones, unbolted the adapter plate and it fell away.

when i put the new grommet in is there anything i can do to stop this happening again? maybe apply a layer of grease between the grommet and plate?

thanks for the advise
Here's a couple of picture's :











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Old 19 April 2010, 10:27   #7
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grommet

SPOT ON , Well done . you must clean up all that salt corrosion around that adaptor plate . Use abit of corrosion free grease when putting that new seal in . Make sure you put two NEW GASKETS ON THERE BUDDY . It will ONLY bite you back when you put it all back together and you later find WATER IN THE OIL .

GOOD JOB
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Old 19 April 2010, 15:27   #8
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got the new gaskets and grommet on order, should be here in a few days.
Dont know how mariner can justify nearly 150 for these 3 bits though...
I'm still really pleased anyway, cant wait to get her back together and running again,
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Old 25 April 2010, 05:34   #9
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All sorted now...

Before:



After :



I reckon i'm lucky it didnt overheat and do any real damage...

What happened to today being the hottest day of the year so far? It's raining here at the mo..
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Old 25 April 2010, 07:12   #10
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Great Job

My old 50 4stroke Merc had exactly the same issue just after I sold it (threads about it on here).....never saw mine...was done by a mech with the new owner (not at new owners cost) amazing just how closed up they get!!

Oh and it's raining here too...

Dan
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