Honda Manual/gear case oil

[flapbreaker]

Couldn't find anything in the manual about changing the gear case oil for my BF90 however the manual for my Classic 8 shows how to do it. I'm just wondering why they left it out of the BF90. Are we suppose to have the dealer do it?

[Notayot]

It works the same way on the BF 90. I can't remember if there is one vent or two, but you fill from the bottom up, closing the vent(s) and then the fill/drain. I do my own twice a year. I have been using the Mercury "red" gear lube, since I had great luck on my previous outboard which was a Merc.

[flapbreaker]

Thanks. I just found it odd that they left it out of the manual. I went ahead and changed it anyway. THe oil that came out looked like brand new. Is that normal for gear case oil?

[journey on]

Well, I have a 2005 BF8D, BF9.9D, etc, owners manual, and on pgs 73-74 it tells how to do it. It goes all the way up to a BF20D.

By the way, all Honda manuals are on the internet, from whence you can download.

Boris

[oldgrowth]

How much oil is in the bottom end of a Honda 50. When I drained mine it seemed like very little oil and took very little when I filled it.
________
Dave

[Notayot]

As far as condition, clean is good. Water or milky color is bad. The bottom plug is magnetic. If it has chips stuck to it, you are having some wear on either the shift dogs, gears or bearings, but it is probably shift dog wear from slow shifting or shifting with the engine above idle. A very fine grey smear is OK, just wear on some part. The quantity for a BF 90 is slightly more than a quart. The BF 40-50 may be less. When changing, make sure the vent is open too, otherwise the oil will not drain, and you cannot get much to go in either. I am sure they are at least 16 ounces or so. There will either be one or two vents higher up than the drain, and the magnetic plug is in the drain. I also change the o-ring or gasket each time the vent and drain.

I change it twice a year, since I don't ever want to find out I ran all summer with salt water in the gear lube. I lost the gearbox on a Johnson 2 hp from neglecting the lube changes.

[naptime]

Dave,

I purchased the service manual for the BF50. The manual indicates about 1/2 quart for the lower unit oil. The older models will take a little over 1/2 quart and the newer models a little less. I have a 2006 model and I believe the manual specifies 4.3 quarts. I am currently out of town, however if you let me know your model year I will look it up when I get home on Wednesday.

Dick

[oldgrowth]

naptime – thank you for the offer. I have the manual at home and on my PC’s. Don’t know why I just didn’t look before I posted the question. Manual says .53 quarts.

I am going to have to pull my lower unit and look at it. I drained & refilled it last month and about a half cup came out. When I refilled all it would take was the same amount until it was overflowing.
________
Dave

[duckman]

I discovered the same thing for my 2004 75 horse Honda manual...no reference to lower unit oil change. Do all the models have oil vents and where on the Honda are they located? Never knew about them before, just pulled the two drain/fill screws

Thanks

[Wefings]

Bottom is fill and drain , top is vent . Sort of a misnomer . It might could be called "overflow".
Marc

[MOOSE]

Also, it is worth noting when changing gear lube, not to chintz on replacing the little plastic washers on each plug. Their cost is negligible but not replacing them can allow water intrusion into the lower unit. How do I know this, one might ask..........?
Al