502 Mag Hours
 

What year 502, and number of hours before a tear down for major work?
How bullet proof are these engines?
I change oil/filter every 30 hours.
Just curious.
2001 Gen VI - OM series motor, 1 season 157 hours.
I was told they only made 800some OM series motors before production stopped.
Thanks in advance.
Bryan

Well I don't know about the OM series but I know the 502 is a solid package. I ran a 1997 502mag MPI for 500 + hrs and only did regular service. It was not driven easy either. 157 hrs should be no problem. Sounds like you run it with 157 in 1 season. :D With your regular service you can do a compression and leak down test to help you know when things start to go down hill. Oil analysis is not that expensive either if you want to take your PM program to the next level. Just my .02

Like P S said,,, with good maintenence,, I wouldnt even think about teardown until 500+ hours,,,,, after seeing mine apart,,, more like 700 hours with the way I take care of my motor,

Just yanked my two 454 mags out of my Formula this winter. Just shy of 700 hrs and everything up to 400 (first owner) was in salt water. The first owner never changed the exhaust manifolds so I had some pretty severe water damage to the heads. :mad: However, the bottom end in these things is absolutely bullet-proof (Steel crank, dimple rods, forged pistons, 4-bolt mains). A good friend of mine owns a local Mercruiser service facility. He said he has customers with over 1000 hrs and still running. I'm sure there is a performance drop off, but the point is they usually won't fly apart. With the service interval you keep and a little restraint on the sticks, these things will last and last.

Good advice!

Right B? :D :eek: :eureka:

what is ease on the sticks, aren't they supposed to be pushed all the way forward all the time
!?

"a little restraint"
I consider myself conservative!
Thanks Bill.... LOL

Bryan

500 hours is a bit of a myth or at least apply's to old engines. In fact it doesn't make sense if the motor has been well maintained and kept stock. Statistically I think most motors turn over ownership several times by 500 and usually they get screwed with in terms of upgrades i.e. blowers etc. If an owner was to keep his motor/boat from 0 to say 7-800 hours and changed the oil religiously like most of us do and conduct corrosion preventative maintenance, ther eshouldn't be a problem. Riser/manifolds being the exception in salt water.

With the 496's with all the built in protection sensors etc. I would expect them to equal or surpass the 502 in durability (stock) hour for hour. Now this doesn't account for drive wear & tear, or consumable parts on and around the engine compartment. Just solid guts and backbone....