1JZ waterpump, that little hole underneath...

[JZA70 R]

Can anyone tell me why there is a little (5mm?) hole on the underside of the 1JZ waterpump? ...its on the front housing and i know water can come out but under what circumstances?

What is stopping water from leaking out that hole? an o-ring? ...i know its not the main gasket.

Sorry i dont have any photos, im hoping those with answers for me will already know what im talking about.

Thanks.

[YLD-16L]

That hole has been on every Toyota water pump I have seen.

Be interesting to here what its exact purpose is.

[wilbo666]

My understanding is that water comes out of that hole when the seal fails.

It indicates that the pump seal has failed.



Cheers
Wilbo

[YLD-16L]

Orsm.

Thanks Wilbo.

[rob]

if you install a pump that has been sitting on a shelf for a long time it can weep slightly, run the car for a heat cycle or two and and it can seal up.

be sure to monitor it carefully tho as the pump could still be a dud or have other problems.

[JZA70 R]

ok well here is the situation.

ive removed a perfectly fine working waterpump. (dont ask) ...it wasnt leaking, making noises or anything.

After removal ive split the front housing from the rear to check the condition of the plastic impeller. The paper gasket was unhurt and remained intact to the rear housing. to re-seal it i used a very fine layer of silastic. i also used some silastic to seal the NEW o-ring on the front of the block. I was very very confident with this whole operation however after reassembling the entire front of the motor, just filling up the radiator, water started leaking from this hole. It wasnt exactly a slow leak either.

I started the car and let it run long enought to open the thermostat but it didnt get any better.

I am completely stumped and very pissed off.

I have another spare (wrecked) waterpump that i had a look at to see what went wrong but its hard to see where the hole goes. What i did find is the hole has nothing to do with the seal of the two housing (which is all i touched really) so im stumped as to what has happened.

[PlacentaJuan]

i dont think that you are supposed to be glueing o-rings with silastic or anything.

a bit of vaso is all you need for water pumps, and oil for oil pumps and fuel for fuel pumps etc....

maybe the glue has prevented the o-ring from sealing properly.

[lexsmaz]

As wilbo said it is a drain hole if the seal is leaking, stops excess water & pressure build up getting to the bearing & also lets you know the seal is not flash, the seal is actually a flat full contact type of thrust seal, i can't remeber exactly what its made from but its like a ceramic / carbon sort of setup ( dont quote me exactly though ) .. but what can happen is that you can get a scum sort of build up on the seal, which allows coolant to seep through .. Now to fix it ... Firstly make sure the w/pump bearings are not worn & all is ok, Then you can actually buy from Holden some brown hard looking pellets, ( CALLED Seal package water pump, part # 92140053 ) crush them up in water & add to the cooling system & run the car, it basically is a slightly abrasive paste & it relaps the seal surface & hey presto leak gone ... i have used it myself & it really works, went from a descent stream to nothing at all even months later ....

Was actually designed for the v6 commodore as they were suseptible to that condition with their genuine coolant ...

Have fun ...

Rob .

[JZA70 R]

i dont think that you are supposed to be glueing o-rings with silastic or anything.

a bit of vaso is all you need for water pumps, and oil for oil pumps and fuel for fuel pumps etc....

maybe the glue has prevented the o-ring from sealing properly.

Appreciate your input. Something to take into consideration i guess.

As wilbo said it is a drain hole if the seal is leaking, stops excess water & pressure build up getting to the bearing & also lets you know the seal is not flash, the seal is actually a flat full contact type of thrust seal, i can't remeber exactly what its made from but its like a ceramic / carbon sort of setup ( dont quote me exactly though ) .. but what can happen is that you can get a scum sort of build up on the seal, which allows coolant to seep through .. Now to fix it ... Firstly make sure the w/pump bearings are not worn & all is ok, Then you can actually buy from Holden some brown hard looking pellets, ( CALLED Seal package water pump, part # 92140053 ) crush them up in water & add to the cooling system & run the car, it basically is a slightly abrasive paste & it relaps the seal surface & hey presto leak gone ... i have used it myself & it really works, went from a descent stream to nothing at all even months later ....

Was actually designed for the v6 commodore as they were suseptible to that condition with their genuine coolant ...

Have fun ...

Rob .

Thanks very much ill give this a try and let you know the outcome. The motor was FULL of sludge and crap and i wouldnt be surprised if there is some debris preventing the seal from.... sealing.

[Robbos_Toyotas]

yeah its the same as a 2jzge pump....sealed by o-ring, the most which you should do to that is put some tap grease or something (petroleum grease will eventually stuff the rubber)

[JZA70 R]

the only reason why i used silastic on the o-ring on the block was because the iron block is unmachined (cast) and heavily pitted and i didnt have faith the o-ring was gonna seal. With the amount i used, i dont think there is any potential for problems.

[jztoyn]

hey todd.quick question.do u have 2 take off the crank pulley 2 remove the lower timing belt cover 2 get 2 the water pump bolts?as im a bit stuck cuz i also have removed my starter motor and dont know another way 2 crack the bolt on the crank pulley?oh and if u need a 1j water pump i have 1 in perfect nick as im in the process of a 2j pump swap..

[wilbo666]

hey todd.quick question.do u have 2 take off the crank pulley 2 remove the lower timing belt cover 2 get 2 the water pump bolts?

Yes, you need to remove the crank pulley.

By the way... I suggest you use the work 'to' as opposed to 2 on this forum... people don't like that sort of lazy English here

Cheers
Wilbo

[JZA70 R]

Ok so i went and started the car again today with the 2nd rad full of tap water and i noticied it didnt even start dripping. warmed it up properly and then dumped the water, did it all again for a 3rd time (and its still not 100% clear!) but now im ready to fill it up with the toyota red.

very relieved, well fingers crossed it stays this way. let this be a heads up for anyone in this predicament in the future.

(oh, well the problem seems to be while the pump was sitting, the o-ring became unseated or sludge stopped it from sealing) after getting some water through it and allowing it to go through a full heat cycle it appears to be back to normal.

[allencr]

+ on much of the above.

(oh, well the problem seems to be while the pump was sitting, the o-ring became unseated or sludge stopped it from sealing) after getting some water through it and allowing it to go through a full heat cycle it appears to be back to normal.

I was told that the leather seal had dried out & caused the leakage through the weep hole after the pump had been removed & empty & not moving for a while. The hole protects the bearing and alerts you when the seal is bad, or it can have some grease when the bearing overheats or some coolant when a wobbly bearing opens the seal


The trick to getting its flat ceramic/stainless/plastic/whatever shaft seal working again is to run it without pressurizing the system from the radiator cap, so the seal can cut through a little corrosion/oxidation that has built up, without it being lubed by the coolant. Leave it on partially - its first stop/click - or leave it off completely for 15-30 minutes, no pressure and it will seal up.
It can be driven without a pressurized system, just moderate & topped up, no AC.