Impeller and drive shaft. front seals between impeller & duct. REPLACEMENT EXPLAINED

[dan144k]

I went to replace my impeller in the fall and ended up replacing my drive shaft because the threads got chewed up during disassemble.

I have reassembled but not water tested, attempting verify my work I did was done correctly.
Another post I have shows the press I made with some threaded rod.

Hoping someone has better details or actual factory descriptions or pictures.
I have searched online and YouTube and found very little specific information

The (service manual) provided very little information regarding replacing the drive shaft, and also shows a simple picture of the two oil seals.

1. I went off old shaft and measured for pressing in the new shaft.
2. The oil seals had metal faces on both, trying to verify correct install and assembly

(I placed metal faces on the outside away from center Part 12,13)
-I think I assembled it wrong -they both should face toward the rear of the boat
-Also when I took seals out of the parts bags- I lost track of which went to which bag.

Thanks in advance for the help
I am sure this is simple for somebody who frequently works on these parts

 

[Speedling]

I haven't done this (yet) but I would think that 12 and 13 kinda sit against each other in a way to lock each other in place, with 2 acting as a kind of pressure seal?
Sorry, figured I would try it out, but I don't have the pumps apart this winter... yet, lol

 

[Julian]

@Murf'n'surf any thoughts on this?

 

[Murf'n'surf]

Sorry, I'm no help on this.

This pic is trying to show orientation of the seals but I don't understand it.

 

[dan144k]

Well I found some more info on the seals. Info may not be exactly for our boats, but I think Yamaha uses a standard design.

I put my seals in wrong, will need to correct over winter.

website link
http://www.greenhulk.net/forums/showthread.php?t=10901

pdf download shows the details

 

[txav8r]

That illustration if the manual may make sense to someone, but not to me either. After reading the additional info you found, placing the two spring ring sides together makes sense, since at least one of the seals, the flat face certainly seals against the duct. And the other would seal against part #2. If this detail could be added to one of the already saved member tips on impeller change, it might be helpful @Julian

 

[dan144k]

Part 13 is a thinner seal (rear seal) (right in all pics)
part 12 is a thicker seal, Has a lip on it,
( I think lip lays flat {compress's outward} when assembled. (forward seal position)
Part #2 would then (looks like washer) compress the seal lip outward

When the two seals are in front of you it looks like the rubber sides would interlock.
(I am pretty sure this is wrong)

I asked the dealer and they did not have a better manual or information available.
Dealer has same pictures we have. Did not have good answer

Also dealer tech told me to use anti-seize or never-seize on the impeller threads.
I showed him in manual where it shows to use loctite 567, He said to use the never-seize. Just an FYI

STILL SEARCHING FOR AN EXACT ANSWER from someone about seals???

 

[dan144k]

I figured out the only way to verify for 100% the front seal direction.
Remove the the other pump and take the impeller off and visually verify.

If anybody has or is taking their impeller off, Please take a picture of front seal.

 

[Cobra Jet Steering LLC]

Check with www.sbt.com they have tutorial sections to help people since they sell all sorts of parts including pump rebuild kits.

 

[txav8r]

Do you have pictures of the recesses that the seals sits in? Seals generally have to be driven or pressed into whatever they seal. I haven't done the job your doing so I don't have first hand experience with or a visual of the job. But the seal is designed to seal. And only one side is a seal, and the other side is a firm surface to be pressed or driven. My guess is the soft flanges (seal) face apart, not together. And that they are sealing from each direction. But again, I am guessing and reading the manual shows the spring sides together and that implies to me, that the firm sides are facing each other, thereby putting the sealing sides away from each other. Seeing what they seat in would be a confirmation to me if the tutorials that Jeff mentions don't provide more assurance. I know how you feel though, it is hard to tackle a job and come across uncertainties!

 

[dan144k]

Well I pulled the other impeller to look at the seal and took some pictures.
Appears as if rubber part of seal faces the front of the boat.

Both Seals OPEN rubber part faces the front of the boat.
And the part numbers from yamaha/manual/online/diagrams all show which seal goes in first.

The washer or part #2 which goes in front of seals and behind the impeller has a recessed part on the rear side.
----My guess is that the gap allows room for the lip on the seal----

 

[dan144k]

Also figured I would also post a picture of the jig I made to press out the shaft.
Used a 2" coupling and 3/8" threaded rod basically.
When you go to reassemble put seals and shaft into freezer overnight

https://jetboaters.net/threads/ar24...ing-to-clean-up-damaged-unit.3664/#post-63134

 

[buckbuck]

Nice engineering. Hang on to that I may need it some day.

 

[buckbuck]

How many hours do you have on those seals? I don't have experience determining if they are bad or not but judging by the pictures they don't look good.

 

[dan144k]

Hi Jim

Boat has 120 hours.
The seal pictures posted 11-22-14 were from the starboard pump (nothing wrong with it), I disassembled mainly to visually verify seal position.
Only took 20 minutes to pull apart. 4 housing bolts (14mm), 1 steering bolt (11mm), break the impeller loose (chain vise and 24" crescent wrench)
- Items for reassembly
1. Gonna use to verify driveshaft position (depth) when I press port side back together
2. Grease the seal that is exposed
3. never-seize the impeller threads
4. Check jet intake silicone and repair as needed
5. Pull cone and check grease, maybe blow out old grease and repack it.

Summary- I ended up ruining my driveshaft. When I went to remove impeller, port side; the threads between impeller and driveshaft got destroyed on both items. I had to replace the port driveshaft and was installing a different impeller anyhow. Was told when I replace the driveshaft to inspect the bearing and replace the seals. When I assembled and rebuilt the unit I was unsure of oil seal position and guessed/assembled (wrong) so I ordered a second set of seals and took everything apart, and finally got accurate info to seal position. Now I have to reassemble everything on both pumps. But I have all winter. Wanted to make sure all was correct to avoid problems/ broken boat, next summer.

 

[txav8r]

It may be back through the thread, but how did you destroy the impeller/shaft threads? Glad you got it all corrected and figured out the seal orientation!

 

[dan144k]

When I was disassembling to install a different pitched impeller.
The threads crossed and gouged between the impeller and driveshaft.
Don't know why, just happen.

 

[dan144k]

I put the boat back together today, had both pumps out, both impellers removed, and one driveshaft/seals removed. Went together well.
Took some more pictures and information for driveshaft position after pressing into the housing.

Drive shaft sticks out 22" from housing to the front, and the lip sits slightly bellow the raised edge (guessing 1/32"), picture shows strait edge across face.
I put never-seize on the impeller threads (dealer mechanic recommend). Manual says to use loctite 567 (white paste)
Also greased the seals and pulled cones and checked bearings and grease levels and condition.

Seal summary.
Both go in with metal part at back of boat, and open rubber seal open to the front of boat.
Thinner seal go into housing first
Thicker, looks like a double lip, seal goes to front of boat. Washer behind impeller pushes on seal.
Flat part of washer against the back of impeller.

 

[itsdgm]

Great info @dan144k thanks for taking the time to post this. I'm sure it will save several headaches for a lot of guys.

 

[Scottintexas]

added to the FAQ