Replacing the Water Pump Seal - Fixed (I think)

[Gary]

I'm trying to replace the water pump oil seal. I got the pump housing off, removed the impeller (exciting because it is left hand thread!), got the mechanical face seal off, but now I'm stuck. I think the oil seal is hiding behind the little steel cup pressed in to the motor housing (see photo below). Trouble is, I can't for the life of me figure out how extract the cup. I've tried pulling with vice grips, prying the edges, swearing, and a few other things, but no go. Seems like I need some sort of tiny gear puller, that can engage the ID of the cup. Any ideas?? I kinda stumped at this point. Thanks! Gary

Here is the water pump with the cover off, showing the impeller. Guess I should have ordered a gasket.


Here's the impeller off, showing the outer mechanical face seal. I think this is to seal water out.


And finally, here is with the face seal removed. I think the oil seal is behind the steel cup. But the cup is pressed in so hard I cant get it out.

[12string]

How about using a small dent puller, drill a small hole and screw it in to the metal cap and then use the side hammer to tap it out.
Or do you meed to save the metal cap. Or did the new sael come with a new cap?

[Gary]

Thanks 12, that should work. I was hoping to save the cup, but maybe it needs to be sacrificed. The Honda replacement (includes a new face seal) is $37. Not sure that it will fit though. That's my biggest worry - that I'll destroy stuff and not be able to replace it.
Gary

[Kiwiscoot]

In your second photo at 10 o'clock position fron the shaft is a small tab-like thing. Perhaps if you used a long nose pliers and pull that towards the shaft and out it could be a type of a lock ring or a way to release it from the housing. I looked at the CFMoto 150 watercooled engine manual, but it only shows the cup with the seal behind it. They suggest using sealant on the cup, so yours may be not that easy to get out as you need to break the sealant's grip.
Good luck . Some peoples moto is : the bigger the problem the bigger the hammer and if you break it, then it needed replacing anyway! ;D ;D Not my moto I must add before you get the wrong impression.

[Gary]

Thanks Kiwi. Unfortunately the tab was debris or an optical illusion. I felt around with my finger, and alas, no tab.

I bought a set of hooked probes, but even they can't get under the edge of the cup. Sort of reminds me of freeze plugs you used to see in cars. Don't know if cars still have these; I remember the way to get them out was to smash through them with a hammer and chisel, then pry them out.

The other thing I was wondering is maybe if I pulled on the shaft with a puller, maybe that would pull the cup out. But it feels pretty solid. I think it is held in place with pressed in bearings. Don't know.

I can get to the backside of the cup going along the gap on the ID. I just can't find anything strong enough to really hook it and allow me to pull with any force. Seems like I need some sort of special tool or puller.

Sure would like to find a non-destructive way to do this.
Thanks,
Gary

[Gary]

Well, I found the cup along with the mechanical seal for only $8.99 at partsforscooters.com. (Should have checked there first!) The $8.99 price is way better than the $37 price for the Honda OEM part from BikeBandit. I ordered one (and a gasket) and no longer am concerned about a "destructive" method of getting the cup out..... I'll get that sucker out one way or another!

I feel better now!
Gary

[12string]

Worrying through problems with these scoots is the fun part of the scoot'n experience. Next to ride'n.

[Gary]

Brute force and ignorance win again! Since I had a new cup on order, figured it was OK to destroy the old one. So I took a pin punch and hammer to the old cup and with a few blows it came loose:


Behind the cup was the oil seal:


I didn't particularly see anything wrong with the old seal, but installed the new one:


Here are the parts. Impeller, washer, old mechanical seal, old cup, old oil seal.


Hope this helps someone. I haven't seen a post on this yet.
Gary

[12string]

Are you going to replace the mechanical seal? It looks like the same style of seal that is used in a pool ump. I had one go bad in my pool. I took the old one out, didn't look like anything was wrong with the old one, replace it and the leak went away.

[earlwb]

Nice going, thanks for sharing.

[Riddick79]

Yep, thanks for the info and pics, Gary.

I think this info and pics are new to the forum. It should be moved to the How-to and Information Database, just so it doesn't get lost here.

[rockynv]

Good going so far. Do a good job cleaning up the gouges from the punch before pressing the new seal cup back in.

Was there a rubber washer behind the cup between it and the bearing?

Looks like the cup was the stationary part of the seal from the pictures so it is good that you are replacing it.

These seals many times will many times look great to the eye but just a minor amount of distortion will make them leak.

[Gary]

Thanks all. I spotted the punch marks too. Guess I got a bit carried away with the brute force part. Will have to clean up the divots before putting in the new cup.

Behind the cup was the oil seal. Its rubber and hard plastic. There was no separate rubber washer (nothing else is shown on the parts diagram either).

I will be replacing the mechanical seal. Comes with the cup. The inner part of the mechanical seal was glued to the cup (the stationary part).

I think the mechanical seal could very well have been the culprit. This seal is supposed to hold back the water. The oil seal is designed to hold back the oil. If water gets past the mechanical seal, I don't think the oil seal will hold it back. The mechanical seal looked to be in pretty good shape, but there may have been some wear and the rubber may have hardened a bit. So I think it was the culprit. It probably wasn't even necessary to replace the cup and the oil seal. Wish I had thought about this earlier.

The new parts are coming US Postal service from Partsforscooters in Florida. Shipping was cheaper than shipping for BikeBandit, which operates out of San Diego. Go figure. Hopefully, I'll get the parts in the next few days and will put everything back together and test it out.

I think I will put oil in the scoot today and see if it pours out the oil seal. Hopefully not!
Gary

[Rockin Ran]

Great job Gary!
I see a very large deep well socket in your future to tap in the cup ... lol.

[Kiwiscoot]

Great job and "good on ya" (as the kiwis would say) for taking a job like this on. Others would've run to the nearest bike shop when they came to that cup.
Ol' Yella will run like clockwork shortly and SYM ( no name yet??) will sleep in the shed.

from cold (-2degC) shaky (7.8 earth quake 400kms away) New Zealand and hopefully I survive the severe 110kph gales predicted for today. Exciting place for sure.

[Gary]

Put oil in the scoot and ran it a bit sans coolant. Oil did'nt come gushing out the oil seal so I may be part way there ....

[rockynv]

Jul 20, 2009 21:52:36 GMT -5 Gary said:

Put oil in the scoot and ran it a bit sans coolant. Oil did'nt come gushing out the oil seal so I may be part way there ....

That was before you put the water pump seal and impeller back on? The pump seal will self destruct pretty quickly if run dry.

You may want to consider lubricating the coolant seal with antifreeze before you assemble it so you don't take any chances on scoring it with a dry start.

[Gary]

Good point on the outer seal Rocky. The inner seal is lubricated with oil so I don't believe it ran dry. In any case, it appears to be holding back the oil.

[yarddogbbq]

the cooling system pressures up and coolant goes to the oil also around the seals somehow.

use a PG coolant and you will have less pressure in the cooling system.

prestone makes "lowtox" and there is a seirra? brand also. Propylene Glycol makes no pressure of its own. used in some airplane engines, so that at high altitude the pressure has no effect. and is run in some bikes and race engines, i use in all engines at my place.

not toxic to animals. or humans.

and cools great.

good job.

yarddog

[Gary]

Well its a little early to declare victory, but I got all the parts back together, took the scoot out for a test ride and all seemed well.

Here's a photo of the new parts - the mechanical seal in the metal cup, the other side of the mechanical seal, and a new gasket:

Here is a close-up of the mechanical seal in the cup:

The mechanical seal was glued into the cup. Had to figure out a way to press the cup back in place. Found some aluminum tubing that was about the right size to fit the rim of the cup:

Cleaned up the punch marks best I could with a Dremel and emery paper. (doesn't look clean in the photo, but felt pretty good):

Then inserted the mechanical seal and cup. Put a little silicone sealant on for good luck. Then seated the cup with a few light blows with a rubber mallet:

Replaced the other side of the seal in the water pump impeller:

Cleaned off the old gasket:

Reinstalled the impeller (Remember left hand threads!) then put the housing back on and reconnected the hose:

Refilled the coolant. Took her out for a test ride. No coolant leaks. Oil is clear. Maybe good to go!