How to change your mechanical seal(water pump)

[beerock]

I pretty much destroy the mech seal to get it out. I use a pair of needle nose pliers and rip out the springed seal so I just have the piece of metal in plain site. I then use a pair of metal cutters and begin to hack the metal piece out by twisting the metal so the seal sort of shrinks onto itself. Once the seal is out I pop out the oil seal and use a comparable size socket to pop the old
bearing out.

When I install the new bearing (I grease the bearing outer race and case) I use a comparable size socket and press the bearing in till its flush with the case.For the water pump shaft oil seal I use a over size socket and press the seal in till flush with the case. Before I press in the mechanical seal in place. I grease the outer part of the seal and the case area. I then line up the mech seal and
press it in as much as I can with my thumb(not much). Once I know it is fairly level I put the pump shaft in.I use the old seal that was on the impeller and put the impeller on the shaft and hold the shaft with a flathead in the notch and tighten it down until it bottoms out. I then loosen it up and add some washers between the old seal and the impeller( to push the seal down further) i put the nut back on and tighten it down again until the outer metal part of the seal is flush with the case(make sure you do not tighten to much or you can break the black part of the seal and start all over again).Once that is done I install and grease the new seal for the impeller and press it in to the impeller and then I apply a liberal amount of grease to the mechanical seal and put it all together.

[Rich250RRacer]

Sounds like a good way to damage the impellar or shaft. The seal should be driven in using the outer flange as the Honda manual says. All you need is the right size socket or a piece of steel tubing that will catch the outer lip of the mechanical seal.

[beerock]

nope, It works like a charm and have done it plenty of times. If someone is weary of trying it then go buy the tool, but its a waste of money.

[kyex40047]

I just take mine to a local honda shop. They charge me 5$ to put it in. Awhole lot easier. How ofter does your alls seals go out? I have replaced like 7 in two years. I don't have that many hours on the motor though. Also which way do you put the oil seal in? The garter spring face. I just want to make sure its in right. Also I put a new mechan. seal in then never rode it for like a month and a half and then I started it up, rode aroud for like 30mins and it started squeeling real bad and stalled the bike out. Could it be a bad bearing?

[beerock]

Ive replaced a bunch of mechanical seals none of them have failed yet. Usually the pump starts leaking when the bearing wears out of spec. the oil seal faces towards the back of the mechanical seal to keep the oil in.

if you have a problem withyour bike post it this is a thread to explain how to replace the seal.

[Cr85rRida]

I have coolent coming out of the bottom of the water pump on my R. Is a mechanical seal the same thing as the gasket? Any idea whats wrong?

[Cr85rRida]

ANy one? i think nno one see's this because its to high up lol.

[beerock]

theres a pilot hole in the bottom of the waterpupmp, if its coming form there you need to replace your mech seal

[Cr85rRida]

seal or gasket or what?? im confuesed not really sure which is which. It only leakes after i shut it off for like one second its a little drop.

[beerock]

look for a small hole on the bottom underneath the pump its called a weep hle, when the seal blows it leaks there..... use your EYES!

[Cr85rRida]

Okay its been awhile but i have taken the cover off and took the shaft and impeller out. Then there was this rubber thing with a spring i pullefd that out as well. Wheres the mechanical seal? Theres that metal thing i cant get out and also the bearing i cant get out how should i go about doing this? how do i know whats reallly causing the leak like how can i tell the seal is damaged?

[beerock]

Originally posted by Cr85rRida
Okay its been awhile but i have taken the cover off and took the shaft and impeller out. Then there was this rubber thing with a spring i pullefd that out as well. Wheres the mechanical seal? Theres that metal thing i cant get out and also the bearing i cant get out how should i go about doing this? how do i know whats reallly causing the leak like how can i tell the seal is damaged?

omg. well you just destroyed the seal if you pulled out the spring, what were you thinking?

the spring and rubber piece with the grey plastic was the mechanical seal. also the part on the back side of the impeller.

i think you need to make a post and try to READ.

[Cr85rRida]

Mabey i wrote it wrong. I didnt take the spring out of the peice. I just removed the whole rubber peice every thing still intact. It slid right off the metal peice.All i have removed was the shaft, the impeller and rubber peice with the spring still in there. What ever else is in there i havent touched. So did i still mess up? I read your first post and i have the metal peice in site. So what should i do? thanks sorry for being iliterate lol.

[bombsquad54]

FYI if you have coolent coming out of the weephole, it might be the waterpump oil seal, located next to the bearing my mechanical seal is brand new and still came was leaking, so i pulled everything apart and the oil seal was broken, not the mechanical.

[Cr85rRida]

Im buying the whole kit oil seal bearing mech seal and gaskets. Thanks for the info tho;)

[bombsquad54]

your a smart guy, its much earier to do it that way than not have to open all back up!:D

[beerock]

Originally posted by bombsquad54
FYI if you have coolent coming out of the weephole, it might be the waterpump oil seal, located next to the bearing my mechanical seal is brand new and still came was leaking, so i pulled everything apart and the oil seal was broken, not the mechanical.

that does not sound right to me, the weep hole is usualy free of oil and coolant. if the oil seal blows, oil will leak through the weep hole and the mech seal will stil be working properly. no coolant will be in the weep hole area if the oil seal blows. if you have coolant leaking in that area there is a sealing problem with the mech seal.

once again stated a little differently.

the area in between the oil seal and mechanical pump are DRY the weep hole is to show failure signs of either the mech seal or oil seal. or water pump shaft bearing.

[DezSled]

Beerock, I just got a hinson cover mod done off of ebay. Did a great job too and a lot cheaper. After changing the seal I have felt abit more drag when hand turning the impeller shaft, when using the washers w/ the used seal your actually seating the mech seal abit further after initially pressing the seal into the case? Thanks

[beerock]

you have to use your eye when your near the "seated" area of the mech seal. the seal will not go in any further then the specified seating area, if it doesit will not seal right and you will probably break the seal if you try it.

usually the new mech seals are tighter when first installed and once they break in they free up.

you put the washers in between the old seal and impeller correct? any other way will damage the seal

[PhilMoore]

If you have the crankcase assembly tool (07964-mb00200), the smaller end of it fits pretty nicely on the mechanical seal flange. I use a plastic dead blow hammer to drive it in.


On one of my 250R's I replaced the mechanical seal twice because it kept leaking. The second time it failed, I realized the large countershaft bearing had spun in the right crank case half. It did not fit tightly. The end of the counter shaft had movement that basically ruined the water pump bearing and all seals involved.

I got a new right case half, but have not put the thing together yet.

During assembly, don't get any oil on the mating surface of the ceramic seal. Wipe it perfectly clean. Use a very small amount of soap for lubricant. I have seen recommendations for mineral oil, food grade lubricant, and soap. I use dial bar soap from the soap dish. Just wet your finger, get a little bar soap on it, and wipe a very light coating on the seal mating surface. I have read Liquid soap is not recommended.

I have done several of these. The one with the bad countershaft bearing seat is the only one I have done twice (well, three times now! ) .:rolleyes:

Dry running the seal will ruin it quick. Make sure the coolant is in the system before kicking it over!

[tito450r]

I change my mechanical seal, oil seal, shaft and bearing on my 310R. The problem is that it wasn't leaking from the small hole of the bottom water pump cover when I first installed. Then I ran it for several minutes and when I look it, it was leaking small drops of coolant. Right now I dissambled again and everything looks fine. The mechanical seal doesn't seems to be broken. What do you think is the problem?

[NJD]

Does anyone have pics or a good diagram of how to perform a complete install. I have checked the service manual but does not help as much as I'd like. Which way do the seals face, and is it ok to install the bearing first on the outside of the cover or do other parts need to be installed before installing the bearing? Any feedback is greatly appreciated. PICS are a big plus.

[JM317]

I just replaced mine in about 10 minutes and it was the first time I've done it. Once the impellar is unscrewed and removed, pull the old seal out with some pliers. Tap the bearing and seal out with a screwdriver or socket. To press the mech seal in, just use a large bench vise and 24mm socket. Place a piece of wood or something behind the back side of the case of course to keep the back from getting damaged by the vise. Place the socket's hollow inner side directly over the edges of the mech seal with the back side of the socket against the other side of the vise. Make sure everything is lined up and even. Crank the vise down. Install the seal and bearing/backside of the impellar seal with another socket (I used a washer inbetween the socket and seal when tapping it), install the impellar again and you're done.

[beerock]

Originally posted by JM317
I just replaced mine in about 10 minutes and it was the first time I've done it. Once the impellar is unscrewed and removed, pull the old seal out with some pliers. Tap the bearing and seal out with a screwdriver or socket. To press the mech seal in, just use a large bench vise and 24mm socket. Place a piece of wood or something behind the back side of the case of course to keep the back from getting damaged by the vise. Place the socket's hollow inner side directly over the edges of the mech seal with the back side of the socket against the other side of the vise. Make sure everything is lined up and even. Crank the vise down. Install the seal and bearing/backside of the impellar seal with another socket (I used a washer inbetween the socket and seal when tapping it), install the impellar again and you're done.


I hope that your seal is not cracked. you can damage the carbon seal using a socket to press it in.

[JM317]

The socket never touches anything other than the outer edges of the mech seal. A 24mm will matchup perfectly, the socket was deep enough to allow all the inner parts to fit inside of it with no clearance issues.

[beerock]

Originally posted by JM317
The socket never touches anything other than the outer edges of the mech seal. A 24mm will matchup perfectly, the socket was deep enough to allow all the inner parts to fit inside of it with no clearance issues.

touching the outer edges of the seal is a bad idea, you can crush/warp the seal if something goes wrong.

if it works for you thats great

[JM317]

Everything went in smooth, I checked it over really well. I didn't see any signs of the metal cripping or bending. The true test will be when I get it back together in a couple of weeks, I'll post the results.

[Meat]

where does one buy a complete gasket and seal kit ??

[JM317]

I used OEM gaskets for the bottomend and cometic gaskets for the topend, but you can get all the seals and gaskets in kit form from Boss Bearing (I think K&S makes them), give them a call and ask for Kyle. The mechanical seal is something you'll have to buy from a Honda dealer.

[JM317]

Originally posted by JM317
Everything went in smooth, I checked it over really well. I didn't see any signs of the metal cripping or bending. The true test will be when I get it back together in a couple of weeks, I'll post the results.
Everything is working great, no issues whatsoever.

[dynofox]

I just replaced my mechanical seal with help from this post, thanks for all the tips! :D

[efi2]

Originally posted by JM317
I just replaced mine in about 10 minutes and it was the first time I've done it. Once the impellar is unscrewed and removed, pull the old seal out with some pliers. Tap the bearing and seal out with a screwdriver or socket. To press the mech seal in, just use a large bench vise and 24mm socket. Place a piece of wood or something behind the back side of the case of course to keep the back from getting damaged by the vise. Place the socket's hollow inner side directly over the edges of the mech seal with the back side of the socket against the other side of the vise. Make sure everything is lined up and even. Crank the vise down. Install the seal and bearing/backside of the impellar seal with another socket (I used a washer inbetween the socket and seal when tapping it), install the impellar again and you're done. DO NOT USE 24mm 0r 25 mm SOCKET THEY WILL DESTROY THE SEAL--USE A 3/4 INCH PVC COUPLER-- A $40.00 LEARNED LESSON
THANK ATV GODS THEY HAD ONE IN STOCK -ONLY AFTER USING OLD SEAL ON THE IMPELLER TO PRESS IN THE MECH-SEAL

[Grande Huevos]

i just purchased a new mech seal, bearing, oil seal and all gaskets including the metal one shipped to my house for $50 from service honda all oem / i have not replaced any of it yet and not sure i wanna take advice from anybody on this thread after reading it!!! sure does seem to b alot of controversy over what works and what doesnt! lol surley it cant b that difficult!

[Pumashine]

Originally posted by Grande Huevos
surley it cant b that difficult!

With the correct tools its a walk in the park. Without the correct tools its like walking barefoot in the desert. I have seen many people destroy the $35 mechanical seal.

The best advice is too use heat. The bearings and seals will come out much easier. 250 degrees is good.

Last time I was pressing in the mechanical seal I broke the water spigot. If you heat to 450 you can even get the spigot unscrewed.

http://i56.tinypic.com/ic7n20.jpg

[beerock]

Originally posted by Grande Huevos
i just purchased a new mech seal, bearing, oil seal and all gaskets including the metal one shipped to my house for $50 from service honda all oem / i have not replaced any of it yet and not sure i wanna take advice from anybody on this thread after reading it!!! sure does seem to b alot of controversy over what works and what doesnt! lol surley it cant b that difficult!


the original how to works, everyone has their way and their two cents about how to do it. The way I explained many years ago, allows you topressin the metal seal with out a special tool and minimal risk of wrecking the seal.

Dont listen to me though, im only one of 3 atv specialists NOTED as one on this webstie.

[wes350x]

I just let a friend replace mine cause I thought he knew what he was doing...he had did his before, well he tapped it in with a 1" pipe. It seemed like it went in real smooth. Well after I put it back on it was dripping from the coolant hole under the waterpump. Anyway I purchased a new seal AGAIN and did it myself with a shop press and a 3/4 white PVC cap...yes platic cap and it worked awsome. I cleaned the area for the mechanical seal good with steel wool and said a few prayers! It works awsome. Thanks to AceCarlos for help with advice too.

[wilkin250r]

Originally posted by beerock
Dont listen to me though, im only one of 3 atv specialists NOTED as one on this webstie.

Holy $#!%, where have YOU been? :huh :p

[beerock]

hahahaha, I been around. Not really into the whole forum thing much anymore. How u been man?

[wilkin250r]

Getting back into things, actually, picked up an old beater, along with a few new friends that are eager to get into the sport.

I'm looking at designing a new ignition system, going to see if I can marry a CR250 and a stock 250r ignition together, should be an interesting project.

[beerock]

for the power of the CR and lights of the trx?

if it doesnt work out just go with the ricky stator, stator, flywheel and rectifier

the best way to go to get what you want if im right as into why your doing it, try and get a PVL digital ignition that u can use lights with.