OchoMarko
Well-Known LVC Member
My Mark Viii keeps saying low coolant but my needle never goes past the "M" on the gauge. Haven't had a chance to ascertain that it is low or full yet. So is the sensor dirty or faulty?
Can we trust the low coolant light?
- Thread starter OchoMarko
- Start date
Lownslowlsc
Dedicated LVC Member
The message triggers when the float in the coolant reservoir gets below a certain point. Wait till the motors cool and fill the reservoir. If it comes back on you got yourself a leak somewhere.
dnsherrill
Dedicated LVC Member
if you need more, add at crossover, don't open the reserve tank except when filling the system after draining/flushing- open crossover when filling at reserve tank
Lownslowlsc
Dedicated LVC Member
I've never opened the xover when topping off the resv. Never had any issues either.
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Sapperfire
Dedicated LVC Member
If the system is completely EMPTY the needle will read in the Normal range because the sensor is now reading AIR temperature.
If your Low Coolant light comes on, find the leak and repair it, do not drive the car until it is repaired
If your Low Coolant light comes on, find the leak and repair it, do not drive the car until it is repaired
driller
Dedicated LVC Member
The time it took to post this was longer than it takes to open the hood and look at the coolant reservoir.
Spree
Dedicated LVC Member
I add to the reservoir unless changing coolant which is never....no leaks. I agree with Sapper tho. Better fix the problem. It's not giving you a warning for the hell of it!
dnsherrill
Dedicated LVC Member
Spree, I'm pretty sure that when 'topping off' coolant is to be added only at the x-over cap; if it's added at the reserve tank it should be burped immediately
Modular97LSC
Dedicated LVC Member
ocho also check to see if the floater isnt stuck on the bottom...sometimes they get stuck and the messege display will keep saying low coolant.
Spree
Dedicated LVC Member
As long as there's coolant in the reservoir tank you should be able to just add there, then it will suck it into the engine.
I always thought that if the tank is empty then add through the cross over and then burp. If the tank is half full just add there and no need to burp. Am I thinking about this wrong? I've only changed coolant once and burped when I was done. My res tank never gets low (no leaks) and my temp always stays on the "A".
chris2523
93 Mark VIII
i always add at the reservoir.
its super easy to check, so you need to check the fluid level ASAP.
i have to add some coolant to my car and my aunts 97 a few times a year. no idea where it goes. both cars run fine.
its super easy to check, so you need to check the fluid level ASAP.
i have to add some coolant to my car and my aunts 97 a few times a year. no idea where it goes. both cars run fine.
DieselDan
Dedicated LVC Member
The time it took to post this was longer than it takes to open the hood and look at the coolant reservoir.
Just go look at your reservoir, if its low, add some to the reservoir. If it is full and the low coolant message is coming on, you have a problem. Once the system is burped and you don't suck the reservoir dry, there is no need to repeatedly burp the system.
OchoMarko
Well-Known LVC Member
Thanks yall, will do this today and an oil change. The guy I bought it from said he recently replaced the radiator so maybe he didn't know how to add coolant properly. It idles like a Rolex and runs perfect though.
driller
Dedicated LVC Member
You can add coolant to the reservoir if it is slightly low, but if the check coolant warning comes on it is really best to add coolant at the crossover tube.
It is easy enough to cold check the coolant at the crossover tube even if the reservoir shows full.
It is easy enough to cold check the coolant at the crossover tube even if the reservoir shows full.
OchoMarko
Well-Known LVC Member
Well that was simple, the coolant level in the reservoir was about an inch below the cold mark, so I started the car and added it to the level and voila, no more low coolant light. Its been idling to NOT so I guess she's good to go.
dnsherrill
Dedicated LVC Member
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several guys already said it, but I'm gonna ask anyways.....if I see coolant in the crossover tube cap, but the reserve tank is below the min when cold, I can open the reserve tank and add it there? I thought for sure I read that it needs to be burped after the reserve tank has been opened.
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that's what I've run into in the past: cold engine, full at x-over but reserve tank is low. If I pour into x-over it overflows but reserve tank level does not rise
Spree
Dedicated LVC Member
Once the coolant is full at the cross over, burped and sealed. You should just be able to add at the reservoir tank whenever you see it low as long as it's not empty. Opening the cap at the reservoir tank shouldn't let air back into the system.
driller
Dedicated LVC Member
When the coolant system is properly full, the coolant crossover tube will be full when checked cold BEFORE you remove the coolant reservoir cap.
If the reservoir shows low, add coolant to the reservoir up to the cold fill line AFTER checking the crossover tube and replacing the crossover tube cap.
After any coolant system service, a cold check at the crossover tube will verify the system has been burped of any air and the coolant reservoir should be at the cold fill line. If the cold check at the coolant crossover shows it is not completely full, fill the system at the crossover and replace the cap. Then check the reservoir and add coolant if necessary.
If you have to intermittently add coolant, there is a leak somewhere. Small leaks at the radiator seams can be difficult to find since they evaporate quickly. If you actually see a leak at the radiator seams, it is usually a rather large leak in terms of coolant loss.
If the reservoir shows low, add coolant to the reservoir up to the cold fill line AFTER checking the crossover tube and replacing the crossover tube cap.
After any coolant system service, a cold check at the crossover tube will verify the system has been burped of any air and the coolant reservoir should be at the cold fill line. If the cold check at the coolant crossover shows it is not completely full, fill the system at the crossover and replace the cap. Then check the reservoir and add coolant if necessary.
If you have to intermittently add coolant, there is a leak somewhere. Small leaks at the radiator seams can be difficult to find since they evaporate quickly. If you actually see a leak at the radiator seams, it is usually a rather large leak in terms of coolant loss.
dnsherrill
Dedicated LVC Member
i replaced the tstat and a couple clamps yesterday, had a leak at the low radi hose to tstat housing, the reserve tank is a bit low..it's still running warmer than it should, I may drain and flush w/ Prestone flush...or just r/r radi; I broke the hex head on the draincock....always something on these ______cars
Lownslowlsc
Dedicated LVC Member
Get used to it.
dnsherrill
Dedicated LVC Member
I have, it's my ball an chain who's still in denial
You may have had problems burping your car. It does not mean that the proper way to top up the radiator is through the crossover tube. Notice the nice cap on your cooling tank with the place to put your hand. You need a 1/4 drive for the crossover tube.
Certainly if you get air in the system the crossover pipe is where you bleed it out.
I have had the warning twice. Both times just bringing the level up to the line makes the warning go away. It is fussy, only a few 100 ml sets it off.