symptoms of water pump failure

[joebarthlow]

When an 02 water pump goes, when are the typical symptoms?

 

A recent inspection mentioned moderate play with the water pump bearing. My thermostat stays in the lower third, not rising past half way. I question whether if it's working now. I have used very little coolant in the last month or two. I've had some heat related issues, thinking perhaps my carb is out of adjustment. 

 

Sorry, I've owned mostly air-cooled vehicles most of my life

[Simeon]

Generally a failed water pump describes either a bearing failure (common from overly tight fan belts) or a failure of the seal (generally accompanied by a failure of the bearings). 

 

If you are not losing coolant and your temperature is good (sounds like it is) then I wouldn’t rush it’s replacement unless it is making strange noises. You can always remove the belt to try and wiggle the pulley yourself and run the engine without the belt (briefly) to determine if it was adding any noise in operation. 

[Mike Self]

Another thing to check...crawl under the car and look directly up at the underside of the water pump.  There's a small weep hole at the six o-clock position.  If you see a whitish trail leading from the hole, that's evaporated coolant, and it's announcing the sooner rather than later departure of your water pump from the functioning category.  

 

To confirm, grab the fan (engine off, of course) and see if you can rock it axially.  If there's more than a few mm movement at the end of the blades, the bearings are failing.

 

mike

[joebarthlow]

1 hour ago, mike said:

Another thing to check...crawl under the car and look directly up at the underside of the water pump.  There's a small weep hole at the six o-clock position.  If you see a whitish trail leading from the hole, that's evaporated coolant, and it's announcing the sooner rather than later departure of your water pump from the functioning category.  

 

To confirm, grab the fan (engine off, of course) and see if you can rock it axially.  If there's more than a few mm movement at the end of the blades, the bearings are failing.

 

mike

 

I'm not sure where the weep hole is at, but there is a bit of coolant show by the arrow. when rocking the fan blade, I do hear a little click, but cannot tell how many mm it's moving.

 

It may be making a weird noise, I cannot tell. I don't know what a failing water pump sounds like.

 

thanks for your reply

 

Edited June 4, 2018 by joebarthlow

[Jbaumshelter]

3 hours ago, joebarthlow said:

My thermostat stays in the lower third, not rising past half way.

I'm assuming that you want it a little higher? If that is correct, maybe your thermostat is failing and not anything to do with the carb or the water pump? I was having that problem this past winter. My car was running in the lower third and wasn't providing hot enough coolant to the heater core to warm up the cabin. 

I switched from a 71° thermostat to a 75° and it sits right in the middle now and the heater was more efficient. 

Previously to that, I had to replace my heater valve because it was worn out and not opening correctly and not allowing coolant to the heater core. Hope any of that helps. 

[joebarthlow]

25 minutes ago, Jbaumshelter said:

I'm assuming that you want it a little higher? If that is correct, maybe your thermostat is failing and not anything to do with the carb or the water pump? I was having that problem this past winter. My car was running in the lower third and wasn't providing hot enough coolant to the heater core to warm up the cabin. 

I switched from a 71° thermostat to a 75° and it sits right in the middle now and the heater was more efficient. 

Previously to that, I had to replace my heater valve because it was worn out and not opening correctly and not allowing coolant to the heater core. Hope any of that helps. 

 

whether it's city traffic or driving hard on country roads or hills, it will barely rise above the blue box on the gage. rare times it will climb to a little below half. I'm not familiar with 2002 thermostats, so I am a little skeptical I'm getting an accurate reading. I don't know what's on it now. I see aftermarket varies between 71-75-80C, but the genuine BMW one doesn't say. Is there a correct spec somewhere? BTW, I don't get much heat in the cabin.

Edited June 4, 2018 by joebarthlow

[PaulTWinterton]

My failures have been more often bearings before seals.  Loud screeching at start up until warm and/or squeal at shut off.  Remove the belt and spin the pump.  If it resists rotation the bearings are failing.

 

Remember there's not a lot in there to go wrong.  Either the bearings seize or the seals leak.  The impeller still spins until it doesn't.

 

Noisy or wet, it's time to replace.

[flagoworld]

So uh... the cooling system is a closed system. If you're "using" any coolant at all, you know you have a problem and must figure out why. You posted a picture showing coolant on the timing cover below the water pump. Now that a leak is confirmed, it doesn't matter whether the pump is failing or the gasket is failing. You should spend the couple hours replacing it. It's pretty easy to do, so I think you should tackle it one of these weekends.

[Stevenc22]

Yeah time to replace the water pump. Also time to pressure wash the underside of that engine so you can figure out where the leaks are coming from!

[joebarthlow]

8 hours ago, Stevenc22 said:

Also time to pressure wash the underside of that engine so you can figure out where the leaks are coming from!

 

it's on my to-do list, thanks

[joebarthlow]

it appears my pump is working, but with heavy play with the main bearing. I picked up a replacement. Looks like I'm running the wrong thermostat and will replace it while in there. Also going to pull radiator, check take it to a local radiator shop for cleaning.

 

The PO replaced many of the hoses last year with IE hoses when he did a flush. should I replace those hoses? I am thinking yes.

[Simeon]

The IE hoses are silicon so are supposed to have a long life. Personally I wouldn’t bank on changing them until I had examined them. 

[Jjmoonen]

I would leave the hoses as well if they are that new. Even OE rubber style hoses should have a fairly long life span.

 

To reiterate the point made about the thermostat. When thermostats fail they usually do so in the open or closed position and will be accompanied by the problems associated with those positions. Stuck open - the engine doesn't reach operating temp. Stuck closed - engine reaches hot quickly. 

 

While not an '02, the concept is the same on all water cooled engines. I just had an old truck with a stuck open thermostat. I could drive it as long and as hard as I wanted and the (working) temp gauge never came off the bottom (cold) mark. Replaced thermostat and it would get up to operating temp in about 5-10 minutes.

[flagoworld]

1 minute ago, Jjmoonen said:

I would leave the hoses as well if they are that new. Even OE rubber style hoses should have a fairly long life span.

 

To reiterate the point made about the thermostat. When thermostats fail they usually do so in the open or closed position and will be accompanied by the problems associated with those positions. Stuck open - the engine doesn't reach operating temp. Stuck closed - engine reaches hot quickly. 

 

While not an '02, the concept is the same on all water cooled engines. I just had an old truck with a stuck open thermostat. I could drive it as long and as hard as I wanted and the (working) temp gauge never came off the bottom (cold) mark. Replaced thermostat and it would get up to operating temp in about 5-10 minutes.

 

I also had a failed thermostat on my daily driver a couple weeks ago. Stuck (partially?) open and the engine would only reach operating temp under high load. Fun stuff.

 

I also agree, 1 year old hoses should be just fine. These things last many, many years, normally.