Logo
FULL SITE MENU

Just trying to get a model year on this 7.5

L

Laurentide

New member
I picked up an old (I know this much) BF75 last week, and it has the worst redneck "paint job" you've ever seen. The serial # is long gone (painted over), and I just want to get an idea what year these cowling graphics were used.

So here's what I've got (sorry for the cell flash photo):

E2yY5VA.jpg


...and here's what the decals should look like:

UQtRQ2L.jpg



It's a CDI model, and the internals look pretty much identical to everything else made up to '97, and a lot like the 8 made post-'97, but I'd still like to be able to order the correct parts. It runs like a champ but needs a few maintenance items.

I guess as a follow up question, just how interchangeable are all of these 7.5's and 10's? Did they change much over the years?

Thanks!

EDIT: Ya, that's an OMC fuel fitting...I'm waiting on the Honda one in the mail.
 
What is the frame serial number? That will tell us for sure. Look on the side or the front of the mounting bracket. It may be painted over. It would be something like BF75-1400000

Mike
 
hondadude said:
What is the frame serial number? That will tell us for sure. Look on the side or the front of the mounting bracket. It may be painted over. It would be something like BF75-1400000

Mike
Click to expand...

Yeah, the plate is there but it is in fact painted over. It's kinda weird because it's Honda blue, but the plate is smooth and number-less.

Is there another # on the block that I can look for tomorrow?

I've seen this cover on a 1980 model, but this one has the green oil pressure indicator light and the kill switch on the tiller. The '80 model had the kill switch where the oil light is on mine. Did they do that maybe in '81 or so?
 
Last edited:
There should be but I am not sure where you will find it...possibly on the front of the powerhead. It may be behind whatever is in front of the powerhead.

I think the number on the powerhead will begin with B or BF 75 with several numbers following. That may even be the same as the frame number....if it is a 7.5.

Mike
 
So I found it on the front of the powerhead...thanks for the tip hondadude. It's BF75s-1300078. I can't find a code translation anywhere, so any assistance would be appreciated. Thanks again!

EDIT: And also the model? I don't see an "s" listed for parts, just "sa." Cheers.
 
Last edited:
Finally got it running right. The timing was off by about 6-7 teeth on the belt. I have no idea how that would happen on a cogged belt, but the shakes are gone and it's running like new after sitting for 10 or so years.

Here's a better photo:

JeN6Rp8.jpg


And a terrible quality video of it running (sound is just as bad, sorry): https://www.youtube.com/watch?v=fuAGDY3MffY
 
It is a 1981. Model Number is BF75B.

If it is a long shaft , it is a BF75BL. If it is a short shaft, it is a BF75BS.

Mike
 
Engine sounds pretty good. As for the paint job....many of the rowing clubs and commercial customers who have Hondas, paint them terrible colors so people will not know that they are Hondas. Hondas are like a magnetic to thieves. These folks are tired of paying for replacement motors.

Mike
 
Thanks very much for the info!

I know that the engine was on a charter boat on lake Champlain back in the 90's, which may explain the paint. I have no intention of changing it.

Thanks again. Cheers.

Andy
 
Good evening, I'm back with a minor issue on this engine. I'm getting water in the gearcase, and it's not the drain/fill gaskets. Gear oil is leaking out of the prop shaft holder (for lack of a better description, it's the part in the photo below), so I'm thinking it's the water seal between the casting and the outer radial bearing. There's about half a spool of mono in there. I have the seal and a new outer o-ring, but I can't figure out how to get that bearing out, and don't want to force anything that shouldn't be forced.

Here's what I'm talking about. I ran out of daylight again but I think it's clear enough:

qdYYwTB.jpg


The housing appears to be beveled to hold the bearing in, so is it two pieces? Do I need a special tool to grab those perimeter castings?

Sorry, I realize I should just have a shop manual but everything has been self explanatory thus far. Thanks!
 
Last edited:
Torch did the trick! Trolled for 6 hours with the new water seal, checked the gear oil and I'm good.

I may have more questions down the road, but for now I'm extremely happy with this outboard. Changed fuel lines/filter, new t-stat, cleaned carb, new impeller, new plugs, adjusted timing, all very cheap (or free) stuff. And I've got a quiet, fuel efficient four stroke for under $300 including parts. I honestly can't see how a brand new kicker could be that much better. Testament to Honda quality (and fresh water) I guess.
 
One more for you guys. Would anyone happen to know the part # for the hotter t-stat for this engine? I run it at low rpms for hours in cold water and it's making oil. Hopefully the hotter t-stat and maybe hotter plugs will fix the problem. I found the plugs but can't find the t-stat specs anywhere. Thanks.
 
If you are using DR5HS NGK plugs, switch to DR4HS. It is a hotter plug. See how that works before changing the thermostat.

I do not know what thermostat would be hotter and also fit in this motor. I would have to compare them physically.

Mike
 
Back
Top