New engine maintenance

robhwa · Posted: Wed Jul 16, 2025 11:10 am Post subject:

one more thing...if you take long trips, you'll want to change the oil with your boat on the water. An oil change pump can do this handily and you won't get any oil in the water. If the oil looks really good after removing it, I often don't worry about the filter for a cycle or two. Your new Honda100 (a fantastic motor IMHO) will let you know if your oil pressure isn't good, but not if the oil has deteriorated. If you haven't done this yet, you'll want to hook up and use the full host of engine information that the built-in NMEA provides. It'll even tell you mpg and estimated range if you put in your total gasoline volume when you fill up. It is truly amazing the difference in mpg at different speeds from trolling below hull speed to full throttle. Here is the link to the oil pump on Amazon...

https://www.amazon.com/6L-Extractor-Automotive-Extension-Bleeding/dp/B0DRVNNSRQ/ref=sr_1_1_sspa?crid=25M1N6VOGKX2L&dib=eyJ2IjoiMSJ9.Ch-kkbJh5XJuvaGOQqUPjtqbK0e9SDNjRAfGYp6c8To65DLIxARwu3mMyj40pX_mPPlUoCWid6uqa4MZEAhD9zYkERvIm6Sh2w6GyX-EI0p54lIPL8OMRbwZ2najW-V_XxKhxEDWgMETOgeubKPz2XYoOzHkeOHUgT1FGDAPyP9KanlmD0hpM0FSQGfgNf_EBeTSoJJeLsdzM6aJQFXgrUzvSYKRNmJ9HBZ64cxKbjCs9Sea4TxmWmq8iOaNJ07_zfyqxax-VTDw4Qb59rAW6eLat_Zt-0nOn1LO8llstgU.CJS6BlvNEsrsl36erupCaNROEpyEA0lwf9-6DVa9HqU&dib_tag=se&keywords=outboard+motor+oil+change+pump&qid=1752678171&sprefix=outboard+motor+oil+%2Caps%2C242&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1

Wood Zeppelin · Posted: Wed Jul 16, 2025 2:17 pm Post subject:

Wood Zeppelin · Posted: Wed Jul 16, 2025 2:49 pm Post subject:

I'm not sure what type of gear oil and oil filter the 2021 BF100A takes. Does anyone know how to find this info for sure?

Boats.net says they need to serial# of my motor to be sure. I don't have that right now.

Wood Zeppelin · Posted: Wed Jul 16, 2025 5:41 pm Post subject:

Got the oil filter. But they won't say what gear oil to use, only that it's found in the SHOP manual, or from a Honda shop... Anyone know?

Salmon Fisher · Posted: Wed Jul 16, 2025 7:05 pm Post subject:

Do yourself a favor and buy the pump attachment that screws onto the bottle. Most of those will have multiple threaded tips for all manufacturers and the Honda, too.

Found a maintenance kit for 90 HP. I would think it would work for 100 HP. Might want to give them a call to find out for sure. Do you have an owners manual? Found an online Honda owners manual and the specs are same for 90 HP as 100 HP.

https://www.boemarine.com/outboards/honda-marine/maintenance-kit.html

ssobol · Posted: Wed Jul 16, 2025 7:27 pm Post subject:

The lower case oil is easy. To empty remove the bottom plug then the top (less oil on your hands). Let the oil drain. Using a pump attachment on the gear oil bottle (commonly available, see example in link below) pump the gear oil into the drain hole until it just starts coming out the fill (top hole). Insert the plug in the top hole, then remove the fill hose and insert the drain (lower) plug.

I change the washer each time. The plugs get changed when the slot for removal tool gets too torn up.

https://www.amsoil.com/p/amsoil-marine-gear-lube-pump-g3456/

Wood Zeppelin · Posted: Thu Jul 17, 2025 3:18 am Post subject:

Salmon Fisher,

yes, thanks for the reminder! I've used one of those before.

Been out fishing lately?

Wood Zeppelin · Posted: Thu Jul 17, 2025 3:51 am Post subject:

ssobol · Posted: Thu Jul 17, 2025 10:54 am Post subject:

Wood Zeppelin · Posted: Thu Jul 17, 2025 4:37 pm Post subject:

Wood Zeppelin · Posted: Thu Jul 17, 2025 4:42 pm Post subject:

Wood Zeppelin · Posted: Fri Jul 18, 2025 10:29 pm Post subject:

Looks like I need a shop manual just to do routine maintenance items. Anyone know where to get one!?

robhwa · Posted: Sat Jul 19, 2025 9:50 am Post subject:

Wood Zeppelin · Posted: Sat Jul 19, 2025 1:21 pm Post subject:

Thanks Robhwa,

Good Point!

BTW, i did a south sound cruise a few years ago and camped at the Eagle Island marine park. Great area you're in!