Mercury 5.0

Mr-G

Recruit
Joined
Oct 1, 2017
Messages
4
Looking to get a used boat that has an I/O mercury 5.0 . I'm not sure how many hours are on the engine. Its a 2006. What should I be on the look out for? What questions to ask the current owner? Thanks
 

tpenfield

Moderator
Staff member
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Jul 18, 2011
Messages
17,625
:welcome:

That is a pretty broad question. Is there a concern about the engine? Tell us more about the boat.

The things to inspect are pretty much the same for any I/O engine.

Outdrive - corrosion
Bellows - cracking/holes
Gear Oil - clean or milky, water present?
Engine (they are GM engines) so the 5.0 is the GM 305 V8
Exhaust manifold and elbow gasket area - are there signs of leakage around the gasket
Any leaks while running
Sea/lake test - does the engine reach it's spec'd RPM at WOT and does the boat go the speed that it should
Compression test - are all of the cylinders within an acceptable range.
Oil condition - before/after running on the lake/sea trial - clean, dark, . . . milky? :eek:
Carburetor or Fuel injected? MPI or EFI?
Engine temperature
Oil pressure
Does the engine have 'open' cooling or 'closed' cooling (Heat Exchanger)
Exhaust system leakage?

Then there is a whole bunch of stuff for the boat. There are checklists that you can reference in the 'stickies' at the top of the forums.
 

KJM

Lieutenant Junior Grade
Joined
Jul 31, 2016
Messages
1,186
I've bought two boats in the past and both had rotten transoms that needed to be replaced, felt kinda dumb the second time. Definitely check that and the floors etc.
 

Mr-G

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Joined
Oct 1, 2017
Messages
4
Thanks. I'll read through the stickies. I don't really have any concerns other than this in my first I/O boat. I've been reading as much as I can and the boat overall looks to be in good condition just needs some cleaning.
 
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