caddison

Got the dreaded "Check Coolant Level" message this morning. I'm asking your advice as to whether I should take it to the dealer and have them check and/or fill it, or just pick up the coolant and do it myself. I know this message is usually the first sign of the headbolt issue, and my engine is in the affected group.

While I think it's silly to have to schedule an appointment and be without my car for the better part of a day for something that is going to take them only a few minutes to find & fill, I also know that documentation is crucial if I end up further down this path and need to make a warranty claim related to the head bolts.

My plan right now would be to buy coolant from my dealer, keep the receipt, monitor what the loss rate is, and actually drop it off if the message comes back up.

Thoughts?

ddcha

makes sense to me.

shades

Have them do it my friend...they can always say you didn't do it properly, therefore denying any claim. believe a day without your cra is nothing...I had the coolest issue done on my car and cane to find out it was the head bolt issue. all the repairs were picked up by MB Canada, and was without my car for a month in the summer time in Toronto....that hurt

shades

Sorry about that sentence....f'ing auto correct

tfthach13

Take it in. I'm at my dealership right now for the same problem. They just told me it was the coolant cap that wasn't holding pressure. They simply replaced it. They checked for the headbolt as well and that wasn't the issue.

mbenzc32

If your car is still under warranty, have it checked by the dealership. That is what the warranty is for. Having to be without your C63 AMG temporarily is a much better option than further damaging the car and any subsequent denials by the manufacturer for any repair claim due to "negligence."

If your car however is out of warranty, I suggest you still bring it to the dealership for assessment and get a second opinion on a reputable German Car Repair shop. This way you know for sure if their assessment are aligned that, that is really the problem (head bolt issue). Hopefully it is just a seal or a lose radiator cap gap. Good luck!

jaykato

C'mon guys. Seriously?
The OP simply needs a little coolant. It happens.
Put some in (himself, not the dealer) and forget it.
If he has the headbolt issue (extremely unlikely), he'll know soon enough.
Right now all he needs is some coolant. That's it.
What's next? Tire pressure down a few pounds means a cracked wheel?
A little common sense please everyone.

ddcha

It's normal for coolant levels to dip a little when it's very cold out. It happened every winter with my GL450. I also had to top off my coolant for my C63 last winter when it was 5 degrees outside. Haven't had any issues since. But I just realized you were in Cali. I'd get it checked.

Clark Kent

My engine is in the affected group as well and I got that warning about two months ago. I followed the Owner's Manual for adding coolant - and haven't seen the light since. My thoughts . . . do it myself first, then if issue persists take it to the dealer.

tfthach13

1. The coolant is a closed system, meaning if the levels are low the coolant must be going somewhere. Adding coolant just masks the problem.

2. Low levels of coolant has been correlated to the headbolts going bad. Would you rather him chance it and have a headbolt snap while he's driving?

3. He's still under warranty; why the hell wouldn't you get it checked out?

4. Low tire pressure can mean there's a slow leak in the tire. What are you going to do? Fill it up with more air and hope it goes away?

To the OP, I would rather have it taken in and have peace of mind rather than always wondering if there is a problem.

Critter

Take it in, peace of mind at the very least, also will show a record if needed to prove previous issue with coolant. I call it insurance for the future. Go test drive cars while yours is in

avery.whss

time to trade it in and get a 14

igor

1. - Since when is coolant a closed system ?! There is a drain hose from the expansion tank on every vehicle I saw at my shop. When weather is hot, your engine is actually reaching higher temperatures so coolant expands and small amount is dispensed through that hose. When it gets cold again, you need to add that amount back. The reason it does not happen on other cars is size and form of expansion tank on MBs plus location of that coolant drain hose.
Just add the coolant and move on. Being doing this for all my MBs every year for the last 10+ years...

2. - If you are constantly loosing coolant, that is a different story and does indicate a problem.

3. - Because you will be billed for any non-warranty related diagnostics/service.

4.- Get the gage and check the tire pressure. Compare to what is specified and if it is the same, might indicate issue with tire pressure sensor so take it in. If you are just loosing air, this will be a non-warranty issue so get an empty spray bottle, put a little dishwashing soap and top-up with water, inflate the tire to around 60 psi. Spray all around the tire - bubbles will indicate where the air leak is...

Igor.

Merc63

Are you sure there is a venting hose on the expansion tank? Isnt that the purpose of the tank?

I remember taking the cap off the tank whike it was warm and it was under pressure... not sure how it would pressurize with a vent tube attached?

igor

I am sure. There is actually a valve on the venting hose and this is why you saw the pressure. Remember that there are no radiator cups on many vehicles so valve is on the hose. It is a bit more complicated than that, but there is a venting hose 100%.

johnnyblaze

I got that light about 6 months ago, added fluid to my window washer fluid, and it never came on again.

Headbolt failures arent as common as we think.

igor

Huh ? What does window washer fluid has to do with coolant ?

roadtalontsi

most would assume nothing... however there is a loop in it that runs coolant through the washer tank to warm it up. ive seen a car leak coolant and cause the washer tank to over flow. not that this has anything to do with what we are talking about. Yes it is a sealed system however it will evaporate on its own some how, just like power steering fluid. If your topping it off more than once every service there is probably some sort of issue. Yes lots of techs are lazy and dont do it, but you never know.

Steve Richo

Agree, before citing chicken little (the sky is falling) more diagnostic info is needed. Might be just normal fluid top up, if you want to CYA you might discuss with the dealer so it is on record.

igor

My question really was - how would topping washer fluid raise coolant level ?

roadtalontsi

i know what you meant just thought id share.

igor

You would be better off topping up the engine oil as it can get into the coolant due to bad headgasket and raise the coolant level. Still cannot find the connection between coolant and washer fluid...

VanC63

dayum

CarHopper

Seems like a headbolt issue and you've potentially lost your motor.

Check out the FAQ sticky, spend some time reading the headbolt threads, but you may want to brace yourself for a long road ahead.

VanC63

Thats the worst reply I was looking forward to reading lol. Is there any recalls on this head bolt issue?