That looks 1" smaller diameter than our 4" one, so probably the 3".

I just replaced the motor in ours last week. I didn't need to cut open anything. The solar panel plastic top lifts off (careful not to break the small wires), pull out the battery, and there is a motor housing with a cap you take off. Then replace the motor and put it back together. The motor is designed to be held down by a screw whose head overlaps the motor body by the slightest amount (a really shoddy design that seems an afterthought). The replacement motor was just a bit smaller so that screw head didn't overlap enough to hold it, so I just hot glued it in place.

I got the motor here: https://www.amazon.com/dp/B0BFXDF9N2?ref_=pe_125775000_1044873430_t_fed_asin_title&th=1

Mark

 

Thanks! I’ll check it out in a week when I’m back at the boat! Hope it’s an easy fix.

 

BTW, these vents really chafe my cookies. They are incredibly expensive, but use the cheapest parts with the most shoddy design and manufacturing, and they fail at an alarming rate. They are one of the crappiest marine products out there. They barely move air - hold a tissue to them and it just slightly responds to the airflow. But once you have cut a big hole in a hatch, or bought a boat with them like us, you have committed to them, or replace the hatch lens. Or try to replace the motor every year or two, or just leave them as a passive vent that works no better than no vent at all.

Mark

 

Mark your experience seems to be the norm unfortunately. Thanks for the info on taking off the solar panel, I’ll take a look. About to start living on board and I’ll need a fan for ventilation.

 

I must be very fortunate. Mine is probably 35 years old? and still works. I have to replace the battery every few years, but it still runs. It does not move enough air to provide any cooling, but it does provide some active ventilation when the boat is closed up.

 

John, to change your battery are you carefully removing the solar layer and accessing the battery area? I'm about to buy the replacement battery and motor and attempt the surgery.

 

I also have had good luck with these fans. i have 2 installed, and only have replaced 1 motor in 20 plus years.
batteries need to be replaced approximatly every 5 years. Keep in mind these are not intended to cool your boat.
they simply insure constsnt air exchange, 24 hours a day,7 days a week, 52 weeks a year

 

I must be very fortunate. Mine is probably 35 years old? and still works.

I also have had good luck with these fans. i have 2 installed, and only have replaced 1 motor in 20 plus years.

We had these vents that were installed in 1998 in our previous boat. They were still working when we sold it in 2019, and I presume still working today.

Fast forward to 2016 or so, and we have had 5 of these fail out of a total of 6. One didn't last 6 months. 2 were replaced under warranty after complaining that they failed just outside warranty. The 6th one is still going, but I expect it to stop any day.

Something has changed in manufacturing or sourcing. I suspect it is seals, since the cause of the 5 failures were the motors seizing up. The o-rings are thin, the housing flanges not true, and the motor sits in a well where any moisture getting in collects.

So if you have old ones still working - congrats, you have the better made ones. If you need to ever change them out with new ones, you too will feel the pain of owning these. BTW - the new ones have a different mount and hole cutout dimensions, even though they are nominally the same as the old, so you will really enjoy the swap!

Mark

 

The o-rings are thin, the housing flanges not true

Can you load them up with Molykote 111? Any silicon grease, but I find this one to be most sticky and durable.

I have a screw down deck plate over my emergency rudder socket. Despite new orings, it still filled with water. I filled the oring grooves, with this grease, like I was packing a bearing.

 

Anecdotally it does sound like the new ones are junk. I’ve never had to do anything to them. Too bad because they do make a huge difference

 

These are the batteries I use. A 4 pack is cheaper than a single "official" one, and they have more capacity.

Amazon.com: Amazon Basics Rechargeable C Cell Batteries, 4-Pack, NiMH, 5000 mAh, Recharge up to 1000x Times, Pre-Charged : Health & Household

Buy Amazon Basics Rechargeable C Cell Batteries, 4-Pack, NiMH, 5000 mAh, Recharge up to 1000x Times, Pre-Charged: Coin & Button Cell - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

For those interested, this was what was inside. All my Amazon motors were the wrong size. This is what was written on the side of the actual motor inside.

 

That's not the motor, it is the battery. The motor is held down by that one screw and has "277 5K26" on it.

Undo that screw and the ring holding the switch in, and the motor will lift out while the battery contacts slide up the channels. Then just unsolder the two leads and solder them back to the new motor.

Yours looks the same as mine, and the Amazon motors fit them.

Mark

 

Mark I posted pics of both for reference. The motors from Amazon were too “short” to fill the space below the battery. Once you get inside, it’s a very simple system. Hope these pics and thread helps others in repairing theirs!