Mercruiser 4.3 LX 205 HP engine life expectancy?

Jmac870

Seaman
Joined
Apr 13, 2014
Messages
53
Looking to purchase my first boat (other than small aluminum fishing/duck boats) and I do not know a whole lot about I/O's. The boat I am currently looking at is an 1989 Sea Ray 220 Overnighter with the 4.3 merccruiser and alpha one outdrive on it. the motor has 760 hours on it but appears to run smooth and looks clean. The price for boat and tandem trailer is also very reasonable. how many hours can you expect to get from this motor on average before a new motor or expensive overhaul is required? it has been used in salt and fresh water. some guys say 1000 hours others say 1500?
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
My previous engine, a 1994 4.3LX is in a friends boat, has just over 2000 hours and it's still going strong...

It's not really about hours as much as how the engine was treated and how well the maintenance was kept up.

That previous engine of mine was always run slightly under-propped, and always had the oil changed every 50 hours....

Another engine that might have been over-propped and only service every leap-year, will be tired and ready for that overhaul at 600 or 700 hours.

Do (or have done) a compression and leakdown test before you commit...

Chris....
 

Jmac870

Seaman
Joined
Apr 13, 2014
Messages
53
Okay thats for input! I plan on checking compression in all cylinders but I do not have a leakdown tester
 

Volphin

Lieutenant
Joined
Jun 5, 2011
Messages
1,405
Look very carefully at those manifolds. If they are original, and salted, they are due for replacement big time.
 
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