BF 30 / BF 25 Impeller fin direction (see pic)

I am embarrased to admit it, but I am second guessing my understanding of what direction the water pump impeller fins are to be facing on my 2001 BF30 (same as BF25).

The pic is of page 12-9 of the shop manual. My confusion is whether the images are of the impeller right side up (as it would sit on the motor) or upside down. I think it is upside down because where my pencil is pointing it shows the keyway opening facing up, and we all know the keyway opening faces down when sliding the impeller down the driveshaft so it can accept the key.

So I get all that, and am pretty sure it is an upside down view, but that would mean that the mechanic of the previous owner of my 30hp installed the old impeller backwards yet it worked 100% fine for over 2 yrs. Previous owner is trustworthy and said he took it to Honda for all servicing. Thats what is bugging me, making the call to go against the direction I know it was previously installed by a Honda tech, and the fact it was working fine and not deteriorating at all after 2 yrs.

I no longer trust my own reasoning abilities and need a second opinion
TIA

Install the impeller on the shaft.--------------------Then lower the pump housing onto it,while turning the driveshaft in the normal direction of engine rotation

Thanks, I will do that if I dont get other replies. I was hoping for a definative answer before breaking it down. Its all put back together. I installed it in the direction IT WAS IN and just now thought to double check it against the manual. Dumb move. Right now the fins are facing the opposite direction as seen in the shop manual image, looking at the impeller upside down.

I ran into the same issue. The manual actually makes it confusing. As racerone says, install as you would expect as you view from above as the shaft would rotate...

I haven't done mine in a couple of years (due now!)
I know in this case it would not be of much help since ou are not sure if it was installed correctly in the first place,
but a good tip for next time,
digital cameras, can take all kinds of pictures before dissambling things and refer back to them for assembly.

My instructions are very clear AND correct.------------Impeller on the shaft ---------Install housing while turning shaft in the normal rotation of the engine !!!!!!

racerone said:

My instructions are very clear AND correct.------------Impeller on the shaft ---------Install housing while turning shaft in the normal rotation of the engine !!!!!!

Click to expand...

We believe you!

I broke mine back down to verify what was correct. Sure enough, the previous owner had my old one on backwards, and so did I since I used his as a pattern. So I used racerone's advise to confirm the proper direction.

For the record, the image in the shop manual is an UPSIDE DOWN view, as if you have the impeller cover in your hand upside down and have inserted the impeller in the cover. Like in this pic:



Previously running the motor, I had confirmed my propeller spins clockwise while in forward gear as seen from the rear of the motor. So to confirm the proper driveshaft direction of spin (in order to use recerone's advise), after I broke it down I made sure it was in forward gear and spun the driveshaft to make the propeller spin clockwise again. I find my driveshaft spins clockwise (as seen from a top of the motor view).

So that would make the impeller fins look like this when the driveshaft spins (remember the driveshaft always spins in the same direction, its the shifting of gears in the gear case that makes the prop spin in reverse):



Here's a silly summary of the two possible views of this thing (sign me up for art lessons):

fff


Kudos to racerone for a great suggestion on how to actually install the impeller. Doing it his way by placing just the impeller itself on the driveshaft first, you are 100% certain the keyway is nested in the keyway channel of the impeller; and only then do you lower the impeller cover down while spinning the shaft to ensure so that the fins land in the proper direction inside the impeller cover. I tested it half a dozen times and each time all fins pointed in the right direction.

Dont forget to grease the inside of the impeller cover so the fins are nice and slippery.

Cheers

Outboards are so easy to deal with !!!