egis

Posting this for my friend.car is overheating when driving but temps are ok when idling.is it possible that water pump shaft spins and fins are not? Is it possible somehow to test it without removing the pump?no leaks on the ground.he mentioned the shaft has a little play.is there any possibility for water pump to fail like that?thanks in advance.

meckert

iTrader: (11)

Multiple issues---if the pump is leaking it needs to be changed, change the thermostat as well and if you still have overheating problems, and you have indeed overheated the engine you will likely need a headgasket. No, the fins don't come off the pump shaft.

heel2toe

iTrader: (41)

How have you confirmed that the car is overheating? It could be as simple as the coolant temp sensor...

hoobastnk90

I would try the thermostat first and if it still overheats then I would check coolant temp sensor..doubt its that but then head gasket

Biggiesacks

How well has the car been maintained? The OEM pump is all metal, it is unlikely that the impeller would come apart. When the car is idling, do the radiator fans cycle on and off periodically once the engine is fully warmed up?

barneyb

Anything is possible. I've seen pictures of water pumps run in cars with only water as coolant and the fins were completely rusted away.

In the pump, other than the impeller, there are two things, a seal and a bearing. If the bearing goes it will wobble or make noise. If the seal goes it will leak. In either case you need a new pump.

egis

Thanks guys.the car is maintained well.30K on original motor. He don't drive much.thats why we are surprised that it having problems out of the blue. Thermo is working. We put it in boiling water and it opened up.the strange thing is when we shut the car off and quickly remove the hose going from thermo to the rad,there's no coolant. It's should be some,right. It makes me think it's freakin pump. And pump is not leaking btw.we can check temp sensor but I doubt it.why you guys think it could be HG?.car don't smoke on idle or while cruising .

barneyb

The most common form of HG failure, at least on the stock engine, is gasses of combustion leaking to the water jacket. That could be the cause of the empty hose.

llDemonll

iTrader: (21)

<p>have the system pressurized so it pushes all the air out. sounds like you just have huge pockets of air stuck in there</p><p>&nbsp;</p><p>easiest way to tell if the pump is working:</p><p>pull thermostat, re-install everything else and fill the car with coolant. pull the radiator cap and start the car. you will see the water flowing</p>

barneyb

I'd suggest replacing the radiator cap. They have a service life of about 30K. It could be that it is not pulling any coolant back from the expansion tank.

Also, check the hoses going to the reservoir. If they are not all tight connections the engine will suck air instead of coolant. In that case you would have coolant forced to the reservoir when the engine is hot and then air pulled in as the engine cools.

If the engine continues to heat, purchase a block test kit from an auto parts store. This is a gizmo that looks like an antifreeze tester. After adding some chemical to the device you sample gases in the radiator. A color change indicates combustion gases.

MyronGainz

iTrader: (6)

I have seen pumps with impellers completely rusted away, so it IS a possibility. On a healthy, well maintained 30k motor though? I dunno about that.

I might have missed it, but i don't think you mentioned anything about the expansion tank. What's going on there? Is it pulling coolant from it/pushing it back, etc?

egis

Thanks for replay.yeah actually it's pushing to expansion tank when he slowly opens the rad cap and then all fluid goes back to the rad.

barneyb

I'm thinking you didn't see this happen and have misconceived what he told you. Pushing coolant to the expansion tank is normal as the engine warms. Pulling coolant back to the radiator after the radiator cap is removed is impossible.

Pushing coolant to the expansion tank until the expansion tank overflows, on the other hand, is a pretty sure sign of a blown head gasket. However, this will probably only occur when the car is driven hard and the head lifts. The only instance where there would possibly be an exception is if the engine hasn't properly been filled with coolant and contains air.

Lombardi23

iTrader: (1)

going to be doing belt soon should i do the pump?

stefenboy

iTrader: (1)

I would always do the pump when doing the belt.

My timing belt was replaced with my waterpump. I tuned the car on 91oct and e85 now im doing head gasket and arp studs because coolant is being pushed to the overflow tank. Overnight the cooling system is still pressurized and when i open the cap i can hear the air pressure that is in the cooling system hissing out. Coolant from the overflow tank is never cycling back into the cooling system because there is constant pressure in the system. I believe that is caused by the slightly blown head gasket. I believe what others stated about combustion gases going to the cooling system to push the coolant to the overflow is true. Because my coolant is never going back to the system im going to replace the head gasket and upgrade to arp head studs. My engine temp never went higher than it should. I never had this issue as my coolant was always at the lower of the bottle until this has happened to me. No oil in coolant, no coolant in oil. Car drives normal and engine temps are normal. Pressure test the cooling system and its good as well. Its weird. Hope the head gasket is the cause.