Besides full fluid and filter change, impellor and coolant for heat exchanger what else would you recommend changing? Motor sat on a pallet for 4 years inside a shop and reads 120 hrs, ran fine owner swithed to diesels. Thanks for the reply
If this engine had been properly put away, the oil and filter would have been changed prior.
Look at the color. If it's clean and with no discoloration, run it!
And again... if put away properly, it would have been fuel enriched protected, since we do not "fog" an MPI engine in the conventional method. Hopefully, the MPI system has survived the 4 years storage.
If concerned with the cylinder walls, find a way to oil wet the ring landings and cylinder walls.
FYI: oiling V-8 cylinders does not accomplish what many think that it does due to the cylinder wall angle.
IOW, gravity causes the oil to roll off the piston decks and it ends up at the low side of the ring landings. So we end up wetting only a small portion of the cylinder walls.
Perhaps try a spray oil via the spark plug ports......., or blast a mist of oil into the cylinders via shop air pressure before you roll it over.
Definitely change the impeller out.
Sitting as rest within the pump body for this long has surely caused it to loose vane resiliency.
Pull the impeller during your next winter lay up..... you'll be surprised at how much longer one will last.
As for the coolant, use an Ethylene Glycol PH balance test strip.
If the PH is OK, run it! If not, change it!
I'd also change out the H/E pencil anode.... or at least examine it.
Have fun!
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