I have searched here and google without finding what I am looking for. If I read the owner's manual correctly, the overflow tank should contain a 50-50 antifreeze mix between the min and max level. In her 2000 Accord, it is near empty. Before I mess up from lack of knowledge, filling the plastic tank to the max mark is necessary, correct?

Also, the picture below is what it looks like under the cover. Is that indicative of a leak of some sort? A few details - EX, 4 cyl, 255k miles, recent minor front end 5 mph bump into an SUV and this picture and empty tank are post-repair of the front end. So far, it seems to run as good as it did before the boo-boo - it's been totally reliable since it was purchased new. The car is going back to the body shop for a follow up visit soon so they might have some adjustment to make from the initial repair. Thanks.

 

Looks like a coolant leak somewhere. If your coolant level is decreasing in the reservoir, then it's going somewhere. A good possibility is a damaged radiator. Cracks in upper plastic top of radiator are not uncommon.

A cold leak-down test should identify the leak site and guide a repair.

good luck

 

You can keep the coolant mix in the reservoir at the max line, that way if the radiator coolant level drops due, the radiator gets extra from the reservoir. You would do the check and refill of the radiator coolant level and reservoir coolant level when it is cool. When it is hot, due to the system being pressurized, the coolant level may go up or down in the reservoir depending on the conditions it is at.

If some or all of the coolant in the radiator was drain and refilled, the cooling system needs to be bled of air. Many times after the drain/fill/bleed, during the next few days, you may need to check the fluid level in the reservoir and top off. What happens is that there may have been or still has a few small air pockets that were in the cooling system that didn't completely come out yet and these small air pockets came out during normal driving conditions (e.g. system gets hot and pressurized, coolant flows through system along with the small pockets of trapped air). When these air pockets come out of the radiator during normal operating conditions, coolant from the reservoir will subsequently be drawn into the radiator, thus lowering the reservoir level.

From the picture, it is not really a certain indicator of any leaks. It may have just been some coolant spraying out when the repair shop was bleeding and re-filling the system and didn't bother to wipe up the spray. Get the car up to normal operating temperature and look for leaks, as the system will be pressurized at normal operating temps.

Keep checking the radiator level and reservoir level when for about a week to see if there really are any leaks. However, at anytime you can look for leaks whether the car is cold or hot.

 

Thank you both for the quick responses and explanations. I will look for any cracks, fill the reservoir to max level and keep an eye on it for her.

 

Picture looks to me like residue of something sprayed or dripped, not a radiator leak. Body shop may have sanded or buffed and then washed the car, but didn't wipe it down under the hood. Wipe it up with wet rag then see if it ever comes back.

Along with the antifreeze mix in the plastic overflow bottle, make sure the actual radiator is full (and bleed out any air). A bad radiator cap can result in the overflow bottle being full while the radiator is not full. But usually you can tell by squeezing the radiator hoses when the engine is cold. Air & liquid sloshing around has a different sound & feel.

 

JimBlake is probably right. I took another look at the pic after JB's post.

It may be the buffing/polishing compound splattering around and got under and between the hood area when they were sanding and buffing the car with an orbital polisher.

 

I have a radiator leak that is spitting out coolant that kind of looks like that on my TSX. I just noticed it this evening.

 

I've had a leaking radiator that produced that characteristic white streaks when dried.

good luck

 

PA- sorry to hear that on your TSX.

Just me but that little rust looking spot in the crease where the upper hose - between the cap and where the hose connection is - looks suspect.

OP-in the repair, was the rad replaced.

 

To follow up, we got the car back from the body shop. Jim was correct about the bad gas cap causing the spray over the hose. On the way home, I stopped at Auto Zone and bought a new one. You folks are good! Thanks again for the help.