Mobil synthetic 75/90 gear oil
#7
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Joined: Nov 2006
Posts: 1,313
Likes: 153
From: Tygart Lake, WV
I ran it in a overpowered Alpha 1 for around 5 years with no problems. The gears looked great every season after teardown. I changed it every 25-30 hrs. This summer I had a leaky seal and water entered the drive. I noticed the gear oil resevoir off color and pulled the boat and replaced the seals and cleaned everything. Gears looked ok. Put it back together and the next change I noticed alot of metal on the magnet. Tearing down the drive revealed the F and pinion gear teeth were coming apart.
Did the Mobil 1 being diluted with water cause this? Would Merc HP Syn have prevented this? It's up in the air but I am switching back to Merc Syn just b/c of this as it supposedly protects better if water enters the drive.
Did the Mobil 1 being diluted with water cause this? Would Merc HP Syn have prevented this? It's up in the air but I am switching back to Merc Syn just b/c of this as it supposedly protects better if water enters the drive.
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