radiator/cooling system question(s).

[Xplorer82]

radiator/cooling system question(s). UPDATE:: new question

i went to check my coolant level the other day (after a 30-40 minute drive, so the engine was Hot) anyway i just had this "urge" to open the Rad. cap just for the hell of it. i know it is a dumb idea, but i know when to twist it back on if i Hear it coming. well anyway, i opened the cap slowly and........ nothing.. no pressure at all even after a long drive and opening up the cap within 2-3 minutes of parking it. just heard a few bubbles in my reserve tank since there was almost nothing in it (water pump is leaking as far as i see)

so why would my Rad not be building up pressure? Thermostat?



now on to my water pump....
i found a leak which looks like it is coming from my water pump area (i will include some pics). now it might not be the water pump it self, it could simply be just a gasket or a hose. i am unsure yet.

i guess my question here is, is there a way to tell if your water pump is bad? i have never dealt with one so they are new to me.


anyway here are the pics i have of where my leak is coming from.(click to enlarge)

my main concern and reason for this thread though is why i have no pressure in my Rad

 

[2000StreetRod]

weap hole

I've read that there is a small hole (weap hole) in the water pump to release any coolant that leaks past the seal. The stains in the photo appear to be on the lower part of the pump as well as the hose. To me that means the pump is leaking and not the hose. If the leak is large enough the pressure in the radiator will bleed off soon after shutting off the engine. Or the radiator cap could be old and no longer holding pressure. If the cap is bad, replacing it will increase pressure in the cooling system increasing the loss of coolant thru the pump leak. Normally the water pump bearing will go bad causing the seal to leak. The pump does not always make a lot of noise when the bearing goes bad. Try grasping the cooling fan blades and rock the water pump pulley from side to side checking for play in the bearing.

 

[Xplorer82]

thanks.
I took a better look at the water pump and it appears to be leaking from the pulley area. i did not try to rock the pulley like you said, i just went and got a new water pump since i am replacing stock parts here and there because of the mileage.

also i am in the middle of a pressure test, my Rad cap is bad. its supposed to hold 16psi, well when i pressurize the cap to 16 it immediately drops to the 13-14psi range. and holds there. one time it dropped to 11psi so i did it again and got the 13psi range again. so im just going to replace the cap as well.



now my new question is, the pressure tester i got from autozone did not come with a manual, so....... when i test the cooling system do i do it with the truck running or off? is there anything special i need to know about doing the test since i didnt get a manual. if someone wants to give me a break down of the procedure it would be very much appreciated. otherwise im sure i'll be able to figure out. it looks pretty straight forward. i just dont know if i need the truck started or not when doing the test.


thanks in advance.

 

[Xplorer82]

just wanted to update.... never mind on the question above about the engine running or not. i got the pressure test done. the radiator holds its pressure and i didnt notice any leaks even from the water pump pulley where the corrosion is and on the bottom of the water pump where more corrosion is. weird, maybe the corrosion is built up bad enough it is like blocking it itself now??

I went out and got a new Rad. Cap and put it on. Yay, i have pressure build up again. so that problem seems to be fixed now. Before i took it for a drive after putting the cap on i made sure the coolant was topped off and i got up under the truck and wiped off all the little drips on the sway bar, ect. went for a 30 minute drive or so parked the truck and got under there, i didnt see any coolant anywhere except one drop on the bottom of the sway bar.


water pump and thermostat next.

 

[Xplorer82]

finally getting around to changing the water pump and thermostat. i got everything ripped apart

got a better look at where the leak was coming from and got some good shots.

one more thing sorry. after i popped off one of the hoses i found this oily substance on the nipple. hose just old and turned it like that? or something more? when i drained the antifreeze it looked fine, still a healthy green color

 

[Xplorer82]

forgot to update.

got it all done about 3 weeks(ish) ago, No Leaks anymore. no more disappearing antifreeze and of course after changing the water pump, thermostat and the Rad cap, i got my pressure back.. Job well done.

 

[2000StreetRod]

Good news!

Glad to hear everything is OK! Thanks for the update.