water pump rebuild
- RHarris
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water pump rebuild
I just put a rebuild kit in my water pump. It is still leaking from the hole in housing. Does any one have any ideas ? I used a new shaft, seal, washer, and impeller. Thanks, Robert.
- wesk
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Was it one of those thin rubber washers or a real packing type seal?
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100
Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100
Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
- artificer
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- Posts: 206
- Joined: Thu Feb 15, 2007 6:00 pm
- Location: Gold Coast Australia
I always eliminate the old style seal running on cast iron & substitute a modern ceramic type...no more leaks ever.
Buy a generic ceramic seal from your local, bearing supplier & a "cut off" bearing.
Buy a generic ceramic seal from your local, bearing supplier & a "cut off" bearing.
John GIBBINS
ASE Master Medium/Heavy Truck & Auto Technician 2002 USA
Licensed Motor Mechanic NSW # MVIC 49593 Current
YOU CAN'T TROUBLESHOOT WHAT YOU DON'T UNDERSTAND
ASE Master Medium/Heavy Truck & Auto Technician 2002 USA
Licensed Motor Mechanic NSW # MVIC 49593 Current
YOU CAN'T TROUBLESHOOT WHAT YOU DON'T UNDERSTAND
- RHarris
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- Joined: Sun Nov 22, 2009 6:00 pm
seal type
The kit had the shaft, a fiber washer with four extensions that fit the impeller,and a rubber ?? seal with a spring around it. The parts looked like the ones I pulled out. Where the seal rides on the housing was nice and smooth. But I am still getting a drip from the hole in the housing. Can you elaborate on the ceramic seal and cut off bearing? Thanks, Robert
- artificer
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- Posts: 206
- Joined: Thu Feb 15, 2007 6:00 pm
- Location: Gold Coast Australia
You should be aware that often a pump with a NOS kit fitted may weep a little till you put a couple of K's on it.....run the engine for 1/2 hour with the radiator cap off.
if the leak is gone do a pressure test or alternatively run with the cap on.
If no leak the seal has been run in & fine for the moment.
What I suggested with the ceramic seal does away with all this stuff & the system will seal straight away.

There is modification very minor about 15 minutes machining to the impeller & housing [any engine machine shop can do if you don't have a lathe] but to get the sealing sorted forever it is a small price to pay.
On vehicles which are not used s a daily driver like these Jeeps leaking water pumps are not uncommon.
if the leak is gone do a pressure test or alternatively run with the cap on.
If no leak the seal has been run in & fine for the moment.
What I suggested with the ceramic seal does away with all this stuff & the system will seal straight away.

There is modification very minor about 15 minutes machining to the impeller & housing [any engine machine shop can do if you don't have a lathe] but to get the sealing sorted forever it is a small price to pay.
On vehicles which are not used s a daily driver like these Jeeps leaking water pumps are not uncommon.
John GIBBINS
ASE Master Medium/Heavy Truck & Auto Technician 2002 USA
Licensed Motor Mechanic NSW # MVIC 49593 Current
YOU CAN'T TROUBLESHOOT WHAT YOU DON'T UNDERSTAND
ASE Master Medium/Heavy Truck & Auto Technician 2002 USA
Licensed Motor Mechanic NSW # MVIC 49593 Current
YOU CAN'T TROUBLESHOOT WHAT YOU DON'T UNDERSTAND
- RHarris
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- Joined: Sun Nov 22, 2009 6:00 pm
modifications
John, can you detail the mods to the pump and impeller for me? Thanks, Robert
- Cacti_Ken
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- artificer
- Active Member

- Posts: 206
- Joined: Thu Feb 15, 2007 6:00 pm
- Location: Gold Coast Australia
Buy a generic ceramic seal from your local, bearing supplier & a "cut off" bearing
I'll have to pull one apart take pics & post in the next few days....John, can you detail the mods to the pump and impeller for me?
John GIBBINS
ASE Master Medium/Heavy Truck & Auto Technician 2002 USA
Licensed Motor Mechanic NSW # MVIC 49593 Current
YOU CAN'T TROUBLESHOOT WHAT YOU DON'T UNDERSTAND
ASE Master Medium/Heavy Truck & Auto Technician 2002 USA
Licensed Motor Mechanic NSW # MVIC 49593 Current
YOU CAN'T TROUBLESHOOT WHAT YOU DON'T UNDERSTAND
- artificer
- Active Member

- Posts: 206
- Joined: Thu Feb 15, 2007 6:00 pm
- Location: Gold Coast Australia
This is how to fix any old vehicle's cheap water pump & in so doing update so you eliminate all the common problems.
It should not be necessary to use hammers @ all & if things are tight you need to use a press or your 6" vyce.

Remove the fan & spacer if there is one

Remove the circlip, There are different type of circlips & some pumps have none


Find the right size drill & gauge the distance from the water pump body & the impeller Set the drill aside as you will need it later

Clean the pump to engine surface thoroughly

Clean the engine to pump surface thoroughly.

! X 5/8" water pump seal kit

Now the critical part....the water pump housing needs to be machined to take the new seal assembly.
Nothing difficult & about 15/30 minutes work for someone that knows what they are doing [like your local machine shop]

They will need your new parts before they start plus the impeller & pump body.

The impeller pictured looks as though something runs against it.
THIS IS NOT THE CASE
The neoprene the ceramic is bonded to fits snugly in there

The parts for a Jeep are a 5/8" water pump seal kit available @ just about any good bearing shop over the counter.
The ceramic [white] portion sizes can vary so ensure you get one similar to the ones in the picture which is only about 1/4" thick with the neoprene.

Clean the machined slot in the water pump body & insert the new seal [the black portion]
with a coat of sealant on the stainless steel sleeve

Get a large socket & you should be able to push in with the palm of your hand

Wipe away excess sealant ensuring none gets on the seal face.

Check the fan mount position on the bearing

Push the bearing into the water pump body from the front [this should be able to be done by hand as well.

Check with your drill again then refit the circlip, now it is a good idea before doing this to put a couple of squirts
of oil in the water pump groove where this clip fits, give it time to run around the inside of the groove....I coat the clip with kopr kote as well.


Now it is time to fit the neoprene mounted ceramic seal to the machined impeller slot....lightly wipe slot with aviation sealer
Smear with a light coating of silicone on the ceramic

Push the impeller home so there is about 0.006" clearance between the blades to the body
Fit your new gasket with sealant, bolt everything up re-fill & pressure test.[/b]
It should not be necessary to use hammers @ all & if things are tight you need to use a press or your 6" vyce.

Remove the fan & spacer if there is one

Remove the circlip, There are different type of circlips & some pumps have none


Find the right size drill & gauge the distance from the water pump body & the impeller Set the drill aside as you will need it later

Clean the pump to engine surface thoroughly

Clean the engine to pump surface thoroughly.

! X 5/8" water pump seal kit

Now the critical part....the water pump housing needs to be machined to take the new seal assembly.
Nothing difficult & about 15/30 minutes work for someone that knows what they are doing [like your local machine shop]

They will need your new parts before they start plus the impeller & pump body.

The impeller pictured looks as though something runs against it.
THIS IS NOT THE CASE
The neoprene the ceramic is bonded to fits snugly in there

The parts for a Jeep are a 5/8" water pump seal kit available @ just about any good bearing shop over the counter.
The ceramic [white] portion sizes can vary so ensure you get one similar to the ones in the picture which is only about 1/4" thick with the neoprene.

Clean the machined slot in the water pump body & insert the new seal [the black portion]
with a coat of sealant on the stainless steel sleeve

Get a large socket & you should be able to push in with the palm of your hand

Wipe away excess sealant ensuring none gets on the seal face.

Check the fan mount position on the bearing

Push the bearing into the water pump body from the front [this should be able to be done by hand as well.

Check with your drill again then refit the circlip, now it is a good idea before doing this to put a couple of squirts
of oil in the water pump groove where this clip fits, give it time to run around the inside of the groove....I coat the clip with kopr kote as well.


Now it is time to fit the neoprene mounted ceramic seal to the machined impeller slot....lightly wipe slot with aviation sealer
Smear with a light coating of silicone on the ceramic

Push the impeller home so there is about 0.006" clearance between the blades to the body
Fit your new gasket with sealant, bolt everything up re-fill & pressure test.[/b]
John GIBBINS
ASE Master Medium/Heavy Truck & Auto Technician 2002 USA
Licensed Motor Mechanic NSW # MVIC 49593 Current
YOU CAN'T TROUBLESHOOT WHAT YOU DON'T UNDERSTAND
ASE Master Medium/Heavy Truck & Auto Technician 2002 USA
Licensed Motor Mechanic NSW # MVIC 49593 Current
YOU CAN'T TROUBLESHOOT WHAT YOU DON'T UNDERSTAND
- wesk
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- Location: Wisconsin
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John,
Can you add the dimensions that will be changed to the old parts illustrations and show the parts again after machining with their new dimensions indicated.
Can you offer up a US made seal kit reference? The Aussie kit in your photo Part Number EN790J10DBQ cannot be found with a google search.
Can you add the dimensions that will be changed to the old parts illustrations and show the parts again after machining with their new dimensions indicated.
Can you offer up a US made seal kit reference? The Aussie kit in your photo Part Number EN790J10DBQ cannot be found with a google search.
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100
Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100
Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
- artificer
- Active Member

- Posts: 206
- Joined: Thu Feb 15, 2007 6:00 pm
- Location: Gold Coast Australia
Would like to help more, sorry I have reassembled now & on the road again, just pulled it down to show the guys how it can be done. This Jeep is my everyday wheels.
Cracked the ceramic while doing so & had to get a new one.
Seal is maybe a John Crane T7? or equivalent but just ask for a 5/8" mechanical water pump seal & this should be accompanied by a dimensional fitting illustraltion from the supplier.
The machinist needs to measure up & it is not difficult. Maybe someone else here with a lathe can complete the write-up with dimensional stuff.
Engine machinists do or I should say did this type repair often & that is where I would suggest folks start with their pump & the kit.
That is what I did when I got sick of leaking seals new or old. I failed to mention that one can up the pressure in the system when using this seal thus increasing the boiling point.
Cracked the ceramic while doing so & had to get a new one.
Seal is maybe a John Crane T7? or equivalent but just ask for a 5/8" mechanical water pump seal & this should be accompanied by a dimensional fitting illustraltion from the supplier.
The machinist needs to measure up & it is not difficult. Maybe someone else here with a lathe can complete the write-up with dimensional stuff.
Engine machinists do or I should say did this type repair often & that is where I would suggest folks start with their pump & the kit.
That is what I did when I got sick of leaking seals new or old. I failed to mention that one can up the pressure in the system when using this seal thus increasing the boiling point.
John GIBBINS
ASE Master Medium/Heavy Truck & Auto Technician 2002 USA
Licensed Motor Mechanic NSW # MVIC 49593 Current
YOU CAN'T TROUBLESHOOT WHAT YOU DON'T UNDERSTAND
ASE Master Medium/Heavy Truck & Auto Technician 2002 USA
Licensed Motor Mechanic NSW # MVIC 49593 Current
YOU CAN'T TROUBLESHOOT WHAT YOU DON'T UNDERSTAND
