Question for Engine Coolant Gurus

[marlonius]

I replaced my upper and lower radiator hoses, radiator, and thermostat about 6K miles ago. Obviously I had the system flushed and filled. Just the other day the Low Coolant light came on when I started her up. I checked and double-checked my upper and lower hoses, t-stat housing and I can't seem to find any leaks. Oh yeah, the water pump was replaced about 18 months ago and that does not seem to be leaking either. So is there somewhere else I should be looking for a leak, or is this a normal condition? I would guess this is not normal. The car doesn't leave any puddles, so if it is a leak I'm guessing it happens when the car is in motion. Any ideas? Where should I be looking for a leak? Thanks.

<small>[ August 07, 2002, 12:25 PM: Message edited by: marlonius ]</small>

 

[ret]

You might want to check the coolant level sensor. It's that plug on the overflow tank, next to the cap. Just pull that out, there will be some prongs at the end, clean them up real nice and put em back in and see what happens. It's fairly common for them to get corroded and so not detect that there's enough coolant.

 

[twr]

Very typical, as the system works the air out it draws coolant back from the overflow bottle. Nothing to worry about, unless it happens a few more times.

 

[SW SHO]

Do you smell coolant burning? Just for good measure, after the car is at operating temp. Look under the throttle body and/or near the thermostat on the tranny. There are several smaller hoses that connect to the underside of the T.B., plus the heater hoses are all there. You may have a small leak coming from one of the fittings, but it won't leave a puddle cuz it'll burn off.

 

[fredhurderjr]

My overflow bottle on my old 93 had a small crack in it.

Also, check the crossover / bypass tube that runs through the center of the "V", between the heads. If it's dripping in there, and burning off, you may never see it.

<small>[ August 07, 2002, 01:40 PM: Message edited by: fredhurderjr ]</small>

 

[marlonius]

fredhurderjr:


Also, check the crossover / bypass tube that runs through the center of the "V", between the heads. If it's dripping in there, and burning off, you may never see it.

Have you seen this happen before? I know these NE winters can be tough on these engines... I'll have to take a look.

 

[sdpatt]

The expansion bottle is vented to atmosphere and a small amout of loss due to evaporation is expected. That is why you are supposed to check the level in the bottle periodically. Now, what you didn't say was whether or not the level was actually low. If not, check the metal tabs on the bottom of the coolant level sensor as previously suggested. If it was low and you see no leaks and it has been at least 6000 miles since you last checked the level, well, you need to check the level more frequently and add coolant and water to make up for the loss due to evaporation. You should be checking the level periodically rather than waiting for the LOW COOLANT beacon on the dash to inform you. That is why they call them "idiot" lights. Be smart. Check it before it calls you an idiot.

 

[marlonius]

sdpatt:
The expansion bottle is vented to atmosphere and a small amout of loss due to evaporation is expected. That is why you are supposed to check the level in the bottle periodically. Now, what you didn't say was whether or not the level was actually low. If not, check the metal tabs on the bottom of the coolant level sensor as previously suggested. If it was low and you see no leaks and it has been at least 6000 miles since you last checked the level, well, you need to check the level more frequently and add coolant and water to make up for the loss due to evaporation. You should be checking the level periodically rather than waiting for the LOW COOLANT beacon on the dash to inform you. That is why they call them "idiot" lights. Be smart. Check it before it calls you an idiot.

Ah, that makes sense. Yes the level was low. There are no cracks in my reservoir. I didn't even think about evaporation. I have to admit that not checking my coolant level often enough is idiotic on my part. Thanks! thumbs_u