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Random Coolant Loss/Quits when Snowing 2 different problems?

1K views 6 replies 3 participants last post by  betherin214 
#1 ·
2000 Astro 4.3 AWD 190k miles approx

Problem One:

Random Coolant Leak. Randomly loses all coolant. No rhyme or reason to it. It happened so scheduled an appointment. Leak didn't happen again of course for months.
So when we took it into to the shop, they did the uv sensitive dye and checked while it was cool and while it was running/warm. Couldn't find a sign of the leak. They thought maybe it was a bad cap and changed it.
It went about a year and then leaked again. Same thing. Dumped all the coolant. VERY careful while driving, the temp gauge is watched like a hawk so if it even STARTS to overheat it's off the road and coolant level checked. It's definitely not been driven overheated to crack or warp the head.
We've had it for YEARS and kept maintenance up on it and the problem didn't start until about 2 years ago. It's been in and out of the shop trying to diagnose it. No obvious signs of an intake leak. No muddy oil, no steam in the tailpipe, no oil in the coolant. Pressure tests show no signs either when the diagnose attempt took place. Definitely an intermittent problem but it happened two times in the past couple months after not happening for nearly a year. Makes me wonder if whatever the problem is has gotten worse or is about to be really bad since it is happening more recurring now.
We have an appointment set up in about 2 weeks to attempt to diagnose it again.
Any ideas on what it could be? Water pump going bad? Want to try to have a few ideas, even off the wall ones to check out.

Problem Two:

Missing when it snows.... and only when it snows. If it has run during a snowstorm and then shut off, sometimes it has trouble starting. Sometimes it misses so badly it will shut off. We avoid driving it in snow now until it's diagnosed to prevent damaging anything. We live in Maine so snow is a frequent occurrence. It would be nice ot have our "goat" of a vehicle to use during the major storms.
New plugs and wires at 175k. Ignition Coil and all surrounding wiring has been changed.
No obvious crack in the distributor cap but could this be the culprit?

This van runs like a top aside from these two problems.
The guys we take it to are the best in the area. Takes two weeks to get in... at all times. They're fair priced and don't overcharge. They also listen if we have any ideas. Looking for suggestions to have them check out since the problem isn't obvious with the tests.

Just to put it out there again, we're using the vehicle very infrequently right now (which is a pain but rather safe than sorry) since the problem has the possibility of being major if driven.

Any help would be great!
 
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#2 ·
Welcome to AS.com my friend!

Sounds like you are suffering from a phenomenon called, "Phantom Coolant Loss" :shifty:

Initially I would guess that it's your water pump. The water pump is funny in a sort of way that when it goes bad sometimes there are no symptoms. No leakage, no noise, no vibration.

This is a result of the engine having a healthy temperature and your drive belt holding everything in place.. but then you have that rare time when the bearing cocks a little to the side and allows the coolant to seep out. Either while you are on the road or in a shopping center parking lot. But you don't notice it because your radiator level remains "normal" while the coolant is seeping out from the top of the engine down to the level of the water pump holes on either side of the block.

And of course it will only fail when the conditions are just right.. so this won't happen in your driveway or while you are under the hood.

So to diagnose this, pull your drive belt off and then spin the fan to listen for any noise. Shake and shimmy it to see if there is any loose play in either direction.

That should give you the answer to your problem. :thumbup:
 
#3 ·
So when you say it dumps out all the coolant, you mean it's obvious under the van that it's puked up coolant on the pavement, or it disappears with no signs of a leak? The only place I would think it could go other than the normal places would be in through the transmission cooler...you'd likely notice something happening though if that were the case.
 
#4 ·
We keep an eye on it, checking it before it goes anywhere.... By dumping coolant I mean that it will be full then suddenly it's all gone. Get it off the road, cool down, refill it and its fine again until it happens again.

So possibility of a bad bearing in the pump?
 
#5 ·
redfury said:
you'd likely notice something happening though if that were the case.
Yes.. you would think... you would think that to be the case. That's why it's called Phantom Coolant Loss. It never happens when you expect it to. Only when you least expect it..and thus not paying attention. e.g. when you are driving in the rain or you are parked on the grass, or driving at night, etc.
 
#7 ·
Thanks. I'm going to mention it to them! Fingers crossed that is it. I will update the topic after taking it in.

The other problem do you think it's possible the distributor cap is cracked or defective and letting the moisture from only snow in?
My guess was the snow is light/floats and can get in and melt moreso than just rain?
 
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