heater hose exploded!!
 

hi guys. I have a 1988 300e. I was inside the car checking my a/c vacuum pods to see which ones aren't working. unfortunately, the center and the defroster weren't working. anyways, after i finished putting everything back together, i tested the a/c to make sure all was well(which thankfully was). but when i went to check out if it heated ok, it started to blow hot air then my heater hose exploded, leaving a puddle of antifreeze under the car. it's the one that connects to the engine behind the air filter housing.
i want to know if i did something wrong or did i just have a old hose or worse.
i added some r134a a couple of days ago cuz it was low and have been using the a/c alot lately, would this have anything to do with that. thanks.

How old are your hoses?? They do have a finite life span. If the hose is origional 1988 -2005 = 17 years ... I'd say they were just tired and died

check these things
 

Hi,

Last time my heater hoses "exploded" rather than just leaked, I had a clogged radiator cap (no pressure release). You may want to check for clogs elsewhere in your system downstream of your pump (like your radiator needs rebuilding/rodding?).

Cheers,
Yoko

well, I changed to hose today and so far so good. maybe it was just the hose since i looked inside and it looked brittle. Hopefully that's all it was, will keep checking on it though. Thanks.

For what it's worth... from my recent research here, the coolant reservoir cap on these cars seem to flake out pretty regularly.

I just replaced my cap (1992 300E) because it was not letting air INTO the system as it's supposed to, which caused collapsed radiator hoses from the vacuum generated when the car cools.

If you have any suspicions of your cap you might want to just replace it, it's only $7.

Your problem is a common one on this chassis....the engine heat and continual engine movement subject this hose to more abuse than any other.
The rear head coolant outlet also corrodes the worst too.... this puts extra stress on the fabric of the hose.

Only the OEM hose will do duty for any time
...system pressure is controlled by the cap.
Maximum of 1.4 +/- 0.1 bar



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