Lower Unit question

[EricD]

I've seen several posts on other forums on this site that mention people changing the oil in their lower unit when they take the boat out of storage. I've done it in the fall. What makes the most sense? Are some people changing it in the fall and the spring? Just curious what I should be doing.

[Pat K]

It's better to change it in the fall. If there is water in the lower unit it can freeze during the winter and crack the housing. Water in the unit can also cause corrosion on the gears and bearings while it sits.

Another advantage is if you do find water in the lower unit in the fall you have all winter to fix it yourself or take it to a shop to have it done without it cutting into your time on the water.

[boatfixer]

Ditto

[EricD]

That's what I kind of thought. I was just wondering if I was missing something.

[delmuts]

I agree to do it in the fall! Example; Years back i bought a boat with a 175 on it late fall. Never really gave the lower unit a thought til in dec. I could barely turn the prop! I was lucky in that it hadn't froze bad enough to crack the housing, but it did take two days in a heated shop with a heat lamp on it to thaw it out so he could work on it. And as said. If there is a problem you have all winter to get it fixed!

[JimBuck]

I typically change mine about 2-3 times a year. She get's a good amount of use and the cost of upkeep is minimal. This way I can notice any irregularities or impurities and address those issues before they turn into a bigger problem down the road.

Here's one for you guys...Is there a cold-weather lower unit oil that is slightly thinner than a standard lower unit oil? I use the boat in some cold water and was curious if there is something better than my usual merc. lower unit oil?