1990's Honda BF2 gearbox removal (to replace impeller)

[tzzuti]

Hello - this is my first time posting on this forum.
I am working on replacing the impeller in this BF2 (BAES) unit. It is from the late 1990's.
It is the type where the engine is air cooled and the shaft is water cooled.
I need to change the impeller as water does not come out of the pee hole.

I have gotten pretty far along with removing the gearbox, but i'm stuck trying to remove the drive shaft pinion (item 11).
I have removed the C clip, but I'm not sure how to remove the drive shaft pinion. I thought it would just come off after I removed the C clip, but it just won't come off.
I have included a picture of the inside of the gearbox and a diagram.
I'm wondering how to get it apart ? Does anyone have any guidance for me ? Do I just use a rubber mallet and hit downward on the cavitation plate to separate ?

 

[QBhoy]

Not familiar with this engine at all and can’t see that drawing properly on the phone here…I may stand to be corrected here and made a fool of…but are you dear sure that’s the right way to go about it ? I know it’s not the conventional arrangement, with just the partial cooling for the mid section and exhaust chamber…but are you not in about the inner or the gearbox there ? Is the pump not on top of the gearbox, once removed in its entirety?

 

[VicS]

Hello - this is my first time posting on this forum.
I am working on replacing the impeller in this BF2 (BAES) unit. It is from the late 1990

I have gotten pretty far along with removing the gearbox, but i'm stuck trying to remove the drive shaft pinion (item 11).
I have removed the C clip, but I'm not sure how to remove the drive shaft pinion. I thought it would just come off after I removed the C clip, but it just won't come off.
I have included a picture of the inside of the gearbox and a diagram.
I'm wondering how to get it apart ? Does anyone have any guidance for me ? Do I just use a rubber mallet and hit downward on the cavitation plate to separate ?

You cannot remove the pinion but with the retaining clip removed the shaft should pull out of it as you remove the gearcase from the leg.

If you have removed both bolts I'd expect the gear case to pull off but I would not hit the cavitation plate with too much force.

 

[VicS]

Not familiar with this engine at all and can’t see that drawing properly on the phone here…I may stand to be corrected here and made a fool of…but are you dear sure that’s the right way to go about it ? I know it’s not the conventional arrangement, with just the partial cooling for the mid section and exhaust chamber…but are you not in about the inner or the gearbox there ? Is the pump not on top of the gearbox, once removed in its entirety?

It is .
The difficulty seems to be separating the gear case from the leg

 

[QBhoy]

It is .
The difficulty seems to be separating the gear case from the leg

Ah. I understand now.

 

[tzzuti]

Thanks for your input/s folks.
Yes, if you look at the 4th picture (the one that show the gears in the gearbox), I would have guessed that once I removed the C clip from the bottom of the smaller gear (item 11) that the gearcase would just slide off. But that's not the case. Not sure what's holding.

 

[Boathook]

Normally you remove 2 bolts, possibly 33 and 34 from the gearbox and the box plus shaft drops away. I can't work out which part number is the impellor plus I thought that these engines were air cooled so no impellor.

 

[jamie N]

Normally you remove 2 bolts, possibly 33 and 34 from the gearbox and the box plus shaft drops away. I can't work out which part number is the impellor plus I thought that these engines were air cooled so no impellor.

BF2.3 is indeed fully air-cooled; the BF2.0 is its predecessor with an impeller, I believe.

 

[DownWest]

Big drift here But a long time ago, when I was about 12, I was given a Clinton 5hp that was aircooled but with an impellor pump to cool the exhaust.
It was siezed, but a piston was available, so I stripped it and polished up the bore, so that was OK. No chance of a fresh impellor, so I fitted a bit of copper pipe into a hole I drilled in the pump housing and ran it out of the exhaust in the cavitation plate and bent it to face the prop. No clutch, so it was always cooled.
My father was hugely amused, but it worked fine. Had a lot of fun with it.
Fast forward to around 1998, when I PXed a job for a Yamaha 3.5. Also aircooled and with exactly the same idea for the exhaust cooling.. Still have it.

Steve65, on here, is a bit of a Honda 2.0 & 2.3 expert, so maybe he can help?

 

[VicS]

Normally you remove 2 bolts, possibly 33 and 34 from the gearbox and the box plus shaft drops away. I can't work out which part number is the impellor plus I thought that these engines were air cooled so no impellor.

The impeller is not shown in the diagram posted but parts #1 and #2 are the impeller housing and its liner.

The impeller is shown in the "Extension case " parts diagram ... q.v.
https://cdn.boats.net/cdn-cgi/image/quality=50/MTA/d/1/NjQ1NjM-10d6d91c.png

 

[tzzuti]

Thanks VicS - Yes the impeller is shown as item 1 here in the extension case diagram.
And the impeller is housed at the top of the previous diagram.
Since I can't seem to budge the lower section that has the gearcase off, even after removing the C clip, do you think I should work on removing the vertical shaft out of the top of the extension case where the shaft goes into the engine area ?