new waterpump leaks when off

[t97]

I just did my timing belts and all the general maintenance and everything went smoothly but for some reason my waterpump leaks. If the truck is running not a drop will come out but as soon as I turn it off it leaks pretty steady. What would cause this did I forget to put something here?

[maxdsm]

They come with a new gasket .Gasket could have torn or not centered correctly .Also make sure it's torqued to spec.

[geezer101]

Is it leaking from the coolant gallery pipe that runs around to the back of the block? Either the 'O' ring is messed up and/or the pipe alignment is out or not pressed in firm enough. You might get away with some sealant. They can be tricky to get to seal up sometimes.

[t97]

It was pressed up as far as it would go I guess it's the only ring then I don't remember there being one on. Thanks for the quick replies

[finalfighter]

i will usually use a small amount of silicon on the gasket and were the o-ring seats in the pump just in case. Also, when you go to put the truck back together after checking the pump and are done setting the timing belt up, fire it up with just the timing belt and balance shaft belts on to see if everything aligned properly. this way if it the balance shafts are not timed correctly you can immediately fix it. make sure thou that nothing will get caught in the timing belt like the spark plug wires and such. the balance shaft belts will make a vibration that you wont miss if they are not 99.99% correct. I do it this way just to save myself the trouble of removing everything again.

Oh and if that's an eBay dnj pump, get rid of it. i bought one and it would do the same thing because it was cast wrong. go with one from you local parts store, they are not expensive at all.

good luck.

[t97]

Yeah everything is lined up good and it runs without vibration. The waterpump was bought at advance auto I'm not sure what brand it was. I will probably go tonight after work and pick up some o rings and seal everything off with rtv as well.

[camoit]

If you didn't put on a new O ring it's going to leek when cold or with out pressure. The pipe may have rust on it.

[t97]

Ok guys i went to the parts store and bought a generic pack of o rings and even used a bit of rtv around it and it still leaks just as bad as before. Do i need to order the o ring from mitsubishi or is my water pump just a little bigger? I bought the pump from advance auto and its from the brand "GMB". The rotor is a different style than the one i took off but im pretty sure that wasn't the original.

Also do you think if i wrapped some plumbers tape on the waterpipe it would hold?

[finalfighter]

is the pump cracked? or did the block crack possibly somehow? check to see if the radiator hose is not cracked and that there is not a pin hole in the pipe with the o ring.

hope you get it figured out.

[geezer101]

...check to see if the radiator hose is not cracked and that there is not a pin hole in the pipe with the o ring.

These pipes are prone to corrosion and it might not have been prevalent before replacing the water pump assembly. They normally get eaten out at the ends of the metal pipe. The one off my engine was so bad it was like a shower head after I chemically cleaned it. The 'O' ring is a pretty thick item so you have to be sure you're using the right one or it won't seal.

[manfredo]

Does anyone know the part number for the water gallery pipe? the one that goes from the back of the water pump to the heater core. Mine is also corroded and is leaking but I can't seem to find a replacement anywhere. I have the g63b engine.
Thanks

[t97]

Does anyone know the part number for the water gallery pipe? the one that goes from the back of the water pump to the heater core. Mine is also corroded and is leaking but I can't seem to find a replacement anywhere. I have the g63b engine.
Thanks

You'll have to find it at the salvage yard or repair yours. Clean it real nice scuff it with some steel wool and use some jb weld. Let it fully cure before you reinstall. How ever you can also put out a want to buy thread and youll possibly find one. I may have one if your interested.

[holydiver]

hey i've got a similar problem. my water pump starts leaking once i shut off the engine. i'm looking to replace the o-ring and hope the whole assembly doesnt need to be replaced.
but also have a Haynes manual which doesnt help me locate anything.
I'm new to maintenance. any advice? any resources?

[Salteen]

torque the pump down to the orrect spec and watch ou for broken bolts.

[t97]

hey i've got a similar problem. my water pump starts leaking once i shut off the engine. i'm looking to replace the o-ring and hope the whole assembly doesnt need to be replaced.
but also have a Haynes manual which doesnt help me locate anything.
I'm new to maintenance. any advice? any resources?

Where exactly is the pump leaking from? If it was me i would just replace the whole assembly its the same amount of work as replacing the o ring. Im sure theyre not too expensive on rockauto.com though. I do know however that advance auto sells just the o ring. Make sure you get a new gasket too. You can use rtv but i prefer the correct gasket.

[Salteen]

i would also clean up the parts there in a kerosene parts washer. or pressure wash it with water, or with soap and elbow grease. either way i would clean it to get it looking nice. no need in putting dirty parts back on an engine.

[holydiver]

Where exactly is the pump leaking from? If it was me i would just replace the whole assembly its the same amount of work as replacing the o ring. Im sure theyre not too expensive on rockauto.com though. I do know however that advance auto sells just the o ring. Make sure you get a new gasket too. You can use rtv but i prefer the correct gasket.

25057all along the arrow and now more significantly near the belt [photo is from 2 weeks ago].
does replacing the water pump assembly require i mess with the timing belt? how long would you estimate a job like that would take?

[geezer101]

There is a bolt sort of behind the belt path IIRC but if you are patient I think you can get to it without removing the belt. In all honesty, taking the belt off and on is a piece of cake. Don't be scared of it, just align the marks @ TDC, put a rotation direction arrow on it with a white marker and even 2 dots to represent the cam and crank marks, undo the tensioner and remove it. This is a good drill for you to learn how to change a belt when it's time.