Merc 80 still leaking?

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floater
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Re: Merc 80 still leaking?

Post by floater »

Alacrity wrote:To save me re-reading the thread
good point, has gone on a bit.

parts from original motor:- leg, gearbox, top spacer block, exhaust tube.

Brand new parts:- inner baffle (came with 1st block) outer baffle, baffle cover.

best of both:- lower bearing cap, cylinder head cover. block (from 2nd motor after a similar episode trying to track down water ingress on the 1st)

Yes I am paranoid no denying it, fueling this is the fine water droplets on the middle two plugs (condensation?) and a very clean plug 4.

I plan to run the motor in a tank again to clear out the fogging oil (which was hampering a comp test) perform a comp test then run up again and pull the power head off quick to see if there is cafe o lait in the exhaust tract, if there is none then there is no water ingress, if there is then I take the pistons and crank out and do another pressure test looking for water in the bores.

Thanks for the help and support. it is good to have somewhere to go for alternative ideas, if there is water getting in it is not coming from the usual suspects

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Alacrity
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Re: Merc 80 still leaking?

Post by Alacrity »

So it appears the only relevant old bit that's been on both motors is the bottom bearing/seal carrier??
Mercs are like women, no 2 are exactly alike. That's what testing is about. In general it is safer to test motors and props than women!

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floater
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Re: Merc 80 still leaking?

Post by floater »

Yes, but I have tried two, one from each motor, the one fitted now is the uglier of the two but swapped to try something different during my early investigations. in all honesty this was not part of the pressure test as my plate fits around and not over it but it does have new seals fitted with threebond and is a chunky piece so (i felt) unlikely to be cracked. I would have liked to have fitted a brand new one but it is no longer available. I have however considered making one eventualy.

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Re: Merc 80 still leaking?

Post by haventaclue »

http://www.miamimarina.com/frontend/lis ... lock=24799 Try here,or even give Bob Grubb a bell at http://www.mercguy.com. Or here,http://store.oldmercs.com/Default.asp ,ask for Chuck. Bob Grubb used to own www.oldmercs.com,but retired five or six years ago.But he still has a stack of parts NOS.
no matter how bad it is,it can always get worse,I'm an optimist

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floater
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Re: Merc 80 still leaking?

Post by floater »

Thanks for the links I will take a look.

below pics of the(chunky) bearing cap on the spare block
Attachments
cap outer
cap outer
cap inner
cap inner
in position
in position

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floater
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Re: Merc 80 still leaking?

Post by floater »

:oops: Embarrassing admision here:-

viewtopic.php?f=17&t=5440&p=18239#p18239

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Re: Merc 80 still leaking?

Post by floater »

floater wrote::oops: Embarrassing admision here:-

viewtopic.php?f=17&t=5440&p=18239#p18239
Basically I have put the lower crank seals in wrong

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Re: Merc 80 still leaking?

Post by Rapier »

Hooray! Must be easily done..
Fasten bra straps and remove dentures...

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floater
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Re: Merc 80 still leaking?

Post by floater »

Powerhead off job but straightforward. Annoyed at myself for missreading the manual so many times, reading what I expected to see rather than what was actualy there.

Centre pic of the 3 above shows the inner seal installed incorrectly with inner seal lips facing inward. :grrr:

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Re: Merc 80 still leaking?

Post by haventaclue »

That's what you call hiding in plain sight.I never noticed :grrr: Well done :thumbsup:
no matter how bad it is,it can always get worse,I'm an optimist

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