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Water pump on the fritz, question about driving

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Old 06-01-2005, 07:07 PM
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Mongo
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Default Water pump on the fritz, question about driving

Hey guys, recently the water pump on the 928 has decided to start leaking. It's definitely time for a replacement. However, it's not noisy enough to the point of notice. The coolant leakage is from the front of the engine. It recently started leaking this past Saturday after I drove it home from my final exam. It was smoking under the hood. When I popped the hood I could see smoke and a 'burnt sugar' smell coming from the front of the motor. The temperature on the car was well below the red. However, it's strange how the water pump bearing isn't noisy after a failure. The belt tension light didn't even go off! I'm taking it in next week to get the pump replaced and am wondering if I should drive it there. We started it this weekend to move it and to check for more leaks. It didn't leak, but the coolant reservoir volume we took notice to since it was full; it's now 1/3 of the full line mark.

Should I tow it next week or fill it up with coolant and drive it the 12 miles to my buddy's shop?
Old 06-01-2005, 07:20 PM
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Jim bailey - 928 International
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Do You feel lucky ? If the pump fails completely it is $4,000-$7,000 to pay to have the valves fixed. So do you pay for a tow $100 or make a run for it ? to be an even money bet the pump only need fail about one time in 60.
Old 06-01-2005, 07:21 PM
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Stig don't drive it, you tow it now.

This happened to me a few months back and resulted in a 2,700 shop bill. It might take alot of other expensive items with it.
Old 06-01-2005, 07:26 PM
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ok this baby sits until next wednesday when the tow guy picks it up. I don't feel like throwing another 5 grand into it after that.
Old 06-01-2005, 09:07 PM
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Originally Posted by Jim bailey - 928 International
Do You feel lucky ? If the pump fails completely it is $4,000-$7,000 to pay to have the valves fixed. So do you pay for a tow $100 or make a run for it ? to be an even money bet the pump only need fail about one time in 60.

I think my pump failed completely, red light, smoke, whole shebang. I've already confirmed the block is okay and all. What else should I look for to to see if I didn't avoid this valve damage?

By the way Tom, Andy, as long as you have those avatars, neither of you can post unless the other one responds immediately
Old 06-01-2005, 10:51 PM
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I agree you shouldn't drive it.

However, mine leaked for nearly a year before I replaced the pump. All the time I thought it was a thermostat housing seal.
Old 06-02-2005, 12:41 AM
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Tony
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Remember the belt tension light tells you just that...The tension on the belt. Thats it.
Your belt could be tensioned perfectly but if the water pump siezed up, you will be dragging a perfectly good, healthy, well tensioned belt over the siezed water pump pulley. It will wont last long.

Old 06-02-2005, 02:37 AM
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No. Don't drive.
Old 06-02-2005, 12:21 PM
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I don't get as to why the light didn't come on still. Maybe because the bearing has not seized or thrown out of alignment into a lot of play?
Old 06-02-2005, 12:50 PM
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My water pump was leaking from the bearing, but it never seized. Of course, it could have seized up.
Old 06-02-2005, 12:51 PM
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The bushing, if it is in fact your water pump, is just leaking. It apparently has not degraded to the point where there is enough play in it to slacken the timing belt. If the water pump is leaking the coolant is most likely dripping out of the weep hole off the water pump pulley shaft.
Old 06-02-2005, 12:51 PM
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They're often bypassed (grounded out) ... but the warning system is not for your pump it's for the belt. So, a dead pump may grind peacefully into the engine block, eating aay at the water passage, and when that stock is all eaten away, it may finally seize ... or it may wobble enough to loosen the belt. OR .... in my case, the "specialist autohaus brainiacs" had overtensioned her ALL THE WAY ... no warning there.
Old 06-02-2005, 02:52 PM
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The light hasnt come on because your bad water pump has nothing to do with belt tension. You could have a solid piece of steel in place of the smooth running water pump pulley. Your belt tension would still be fine but the belt would go up in smoke in a matter of minutes....which is what you setting yourself up for. Also, remember the clearance on the impeller and the block isnt much either.


Old 06-02-2005, 04:17 PM
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Originally Posted by Tony
The light hasnt come on because your bad water pump has nothing to do with belt tension. You could have a solid piece of steel in place of the smooth running water pump pulley. Your belt tension would still be fine but the belt would go up in smoke in a matter of minutes....which is what you setting yourself up for. Also, remember the clearance on the impeller and the block isnt much either.


I beg to differ Tony I once dodged a cannon shell when my water pump failed catastrophically without much warning. It still turned but the bushing was gone, the pulley was just 'flopping' around in there. Believe me, that had a significant effect on the belt tension and did result in a warning light. Luckily for me, no harm, no foul as the belt never skipped. If the belt tension were marginal to begin with, the looseness of a failing water pump bushing could cause a warning light.
Old 06-02-2005, 07:09 PM
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There is a weep hole in the bottom of the pump casting for this very reason. When the shaft seal failes, fluid goes by the seal lip, down the inside of the pump housing, and out the weep hole. Now, this hole is pretty small, and is only intended to sacrifice a small amount of water/coolant and protect the front bearing.

You would probably be fine taking 12 miles, but it's a chance. There's no reason to add coolant, just add plain old water. The risk as stated is if the bearing siezes, it takes out a lot of innocent but costly valves with it. I would tow or trailer it until it's fixed, but you could take the chance.

Doc


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