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rkmason
12-03-2007, 04:44 PM
Has anyone done a complete teardown of a Johnson Pump F6B-9 crank-driven raw water pump? How does the driveshaft come out? Is it pressed out leaving the water seals and driveshaft bearings in the housing? Thanks

Sodar
12-03-2007, 04:49 PM
I took my pump into the local guy last year with new bearings, seals, impleller, etc. He said "just buy a new pump" So, I figured why not destroy this one if I am going to have buy another one!?!

To answer your question, yes the shaft is pressed in. I had a problem when I pressed mine out, half the bearing stuck to the shaft. I ended up needing to get a bearing puller to get it off. I ended up getting the whole thing rebuilt and mounted, but it had an ugly wobble to it, so I ended up just buying a new one for $130.

Jim@BAWS
12-03-2007, 05:01 PM
Don't waste your time. 3 hexhead screws and one at the base of the pump and you are done. A rebuild kit with a bearing kit is about $60

No guarentee that it will work

Just buy a new pump. A new impeller comes with it

Jim@BAWS

beef
12-03-2007, 07:50 PM
Don't waste your time. 3 hexhead screws and one at the base of the pump and you are done. A rebuild kit with a bearing kit is about $60

No guarentee that it will work

Just buy a new pump. A new impeller comes with it

Jim@BAWS

+1

I researched the rebuild this past summer and just decided to buy a new pump. Installed it in 15 minutes and back to skiing. Done.

rkmason
12-04-2007, 09:55 AM
I already have a new replacement pump; just considering a total rebuild of my old pump so I can start swapping the two periodically. I hate to just throw the old one away if I can rebuild it. Maybe I'll take a shot at the rebuild and if it gets messed up THEN I'll toss it.

rkmason
02-23-2008, 07:25 PM
Well, I went ahead and rebuilt my old raw water pump just to see if I could. I have it back on the boat and it runs fine w/no leaks.

The tricky bit was pushing the driveshaft and bearings out of the pump housing without damaging anything. When Johnson builds these pumps they make sure the bearings stay in the pump housing by hammer punching the bearing housing OD in one spot. I drilled that hammered spot out to help relieve the pressure and the bearings and shaft came out without much trouble.

I found the SKF brand bearings and an near-OEM equivalent water seal at an online bearing supply house. My total parts cost was about $20. If you are willing to use Chinese no-name brand bearings the parts cost can be reduced to about $10.

To retain the bearings I drilled and tapped three holes around the bearing housing for very short 8-32 setscrews. Now I have a pump I can easily rebuild the next time.

So you can rebuild your raw water pump yourself if you are so inclined. Most people will still probably just buy a new replacement, but where's the fun in that?

TMCNo1
02-23-2008, 07:53 PM
Thanks for the effort and the information for those with Johnson pumps!

Prostar Rich
02-24-2008, 04:41 PM
I don't mean to get off subject but how long does the raw water pump last? What kind of life did you guys get before rebuilding or replacing?

Thanks,
Prostar Rich

Slinkyredfoot
02-24-2008, 05:18 PM
With the exception of replacing impellers over the years, I finally totally rebuilt my original last winter for the first time, a 1979 PCM.

rkmason
02-24-2008, 11:36 PM
I don't mean to get off subject but how long does the raw water pump last? What kind of life did you guys get before rebuilding or replacing?

Thanks,
Prostar Rich

The pump I rebuilt was 10 years / 470 engine hrs old. I cannot say there was really anything wrong with either the bearings or the seal that I replaced so I guess it had some (maybe alot) of life left in it. I did my pump rebuild more just to see if I could do it myself. I'll definitely go longer this time around.

Prostar Rich
02-25-2008, 04:22 PM
The pump I rebuilt was 10 years / 470 engine hrs old. I cannot say there was really anything wrong with either the bearings or the seal that I replaced so I guess it had some (maybe alot) of life left in it. I did my pump rebuild more just to see if I could do it myself. I'll definitely go longer this time around.

Thanks for the info. Last year I has chasing down an overheating issue and the RWP checked out however the boat is a 1990 with about the same hours as listed above. I was just wondering what kind of life I should get out of it.

Thanks again,
Prostar Rich

Tom023
02-26-2008, 01:18 PM
You might want to take a look at this, posted by Engine Nut sometime ago. I disassembled mine to replace the shaft seal without any special tools, but if you are replacing the bearings, looks like some are needed.

flipper
02-26-2008, 01:39 PM
I have to agree with most of the above....get a new one. Much less of a head ache, and no worries of messing something up, and having to replace it anyway.

rkmason
02-26-2008, 05:51 PM
You might want to take a look at this, posted by Engine Nut sometime ago. I disassembled mine to replace the shaft seal without any special tools, but if you are replacing the bearings, looks like some are needed.

Yes, that is pretty much exactly what I did, but without the luxury of a press. At a minimum you do need a puller to get the bearings off of the pump shaft.

Chief
02-23-2013, 07:27 PM
After tearing mine out today, I think I will buy a new one. I have a small leak and as much as a pain it was to get it out, I'm not risking a rebuild!

Snipe
02-23-2013, 08:43 PM
Don't waste your time. 3 hexhead screws and one at the base of the pump and you are done. A rebuild kit with a bearing kit is about $60

No guarentee that it will work

Just buy a new pump. A new impeller comes with it

Jim@BAWS
I'm with Jim

GoneBoatN
02-23-2013, 10:05 PM
Funny, I've always wondered about this. I too figured it was easier and cheaper in the long run just to replace. Nice to know I'm not the only person on that bandwagon.

mikeg205
02-24-2013, 11:34 AM
Gotta go +1 on a new pump.... $250 - cheap insurance and piece of mind... $200ish if take the cost of impeller out.

Plus it's new and shiny...lol

homer12
03-14-2013, 01:33 PM
I am in the processing of just doing the seal on mine. The bearings seem totally fine. I have the shaft and bearing out and was able to put the pump upside down in the bench vice with the flange on the housing against the vice and pound out the shaft. I used a hammer and a solid round piece of stainless I had about the same diameter as the shaft. Will post pics when I get done.

CantRepeat
03-15-2013, 08:36 AM
I am in the processing of just doing the seal on mine. The bearings seem totally fine. I have the shaft and bearing out and was able to put the pump upside down in the bench vice with the flange on the housing against the vice and pound out the shaft. I used a hammer and a solid round piece of stainless I had about the same diameter as the shaft. Will post pics when I get done.

For future reference I would recommend a brass drift or punch if you are going to use the hammer method to extract the pump shaft. Using a softer metal drift will have a lesser chance to damage the shaft when compared to a SS drift.

Snipe
03-15-2013, 08:42 AM
For future reference I would recommend a brass drift or punch if you are going to use the hammer method to extract the pump shaft. Using a softer metal drift will have a lesser chance to damage the shaft when compared to a SS drift.
+1:noface::noface::noface:

homer12
04-07-2013, 10:41 PM
I agree with you guys on not using a brass or similar softer metal drift for shaft extraction. I will do differently in the future. For those without an arbor press, here's the method I used to put the shaft/bearings back in the housing. I used long bolts through the flange on the shaft and then used part of a harmonic balancer puller. I went slowly turning each bolt about a 1/4 turn each and pushed it back together nicely. We'll find out how successful this was when I get her out of storage and fired up.

CantRepeat
04-08-2013, 11:26 AM
I agree with you guys on not using a brass or similar softer metal drift for shaft extraction. I will do differently in the future. For those without an arbor press, here's the method I used to put the shaft/bearings back in the housing. I used long bolts through the flange on the shaft and then used part of a harmonic balancer puller. I went slowly turning each bolt about a 1/4 turn each and pushed it back together nicely. We'll find out how successful this was when I get her out of storage and fired up.

Might be some confusion here. I am suggesting that you DO use a softer metal if you are going to hammer the shaft out.

homer12
04-08-2013, 11:53 AM
Might be some confusion here. I am suggesting that you DO use a softer metal if you are going to hammer the shaft out.

That's correct. I agree with you. Need to use brass or something softer than stainless.

pbgbottle
05-04-2013, 10:58 PM
i just ordered a new one yesterday. so today while i wait for it to be shipped i took the old one apart .just wacked shaft, it slid out , didn't mess with pulling bearings. popped the side cover off the accessible bearing. threw some greae back in it .popped the side cover back on bearing.
put the shaft on a piece of wood. put the body on the bearings put a piece of wood over the end and gave it a couple wacks and she slid home .no need for special tools .unless u are pulling the bearings from the shaft. there isn't much to these things .i wouldn't hesitate to ever rebuild one of these , theres nothing to them. no biggie. i most likely will find some bearings for this old one and keep it for a spare. no need to blow a couple hundred dollars. if ya can change a damper plate , or your old manifolds and risers . to rebuild this pump is a piece of cake.


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