99 C43 coolant leak at expansion tank outlet
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From: America
1999 C43 AMG, 2005 E55 Wagon
99 C43 coolant leak at expansion tank outlet
It's been going on for a year now, but has finally gotten to the point it's annoying me.
It's a new radiator hose, original radiator.
I noticed a very slight drop of coolant after driving, dripping very occassionally from front of the engine. I noticed it was coming from the top of the radiator near the tiny outlet to the small hose that runs to the overflow/expansion tank.
Not really a serious leak, and only required topping off every month or two. Well, now that I've fixed the AC and drive the car daily, the leak has become a problem.
I've traced the leak back to that spot multiple times, because it didn't make sense. The leak is coming out around the hose where it meets the inlet. There appears to be no crack or damage to the radiator out the outlet, and the hose is new! I assumed the little hose clamp there might have lost its tension, so I replaced it with a typical adjustable hose clamp and tightened it a great deal (but didn't tighten it enough to break the radiator, it is plastic you know). Still leaks.
Any ideas? My wife is yelling at me to buy a new radiator, but that obviously would be a waste of money. Even in traffic with AC on, it never reaches 100C so the rad is still cooling fine.
It's a new radiator hose, original radiator.
I noticed a very slight drop of coolant after driving, dripping very occassionally from front of the engine. I noticed it was coming from the top of the radiator near the tiny outlet to the small hose that runs to the overflow/expansion tank.
Not really a serious leak, and only required topping off every month or two. Well, now that I've fixed the AC and drive the car daily, the leak has become a problem.
I've traced the leak back to that spot multiple times, because it didn't make sense. The leak is coming out around the hose where it meets the inlet. There appears to be no crack or damage to the radiator out the outlet, and the hose is new! I assumed the little hose clamp there might have lost its tension, so I replaced it with a typical adjustable hose clamp and tightened it a great deal (but didn't tighten it enough to break the radiator, it is plastic you know). Still leaks.
Any ideas? My wife is yelling at me to buy a new radiator, but that obviously would be a waste of money. Even in traffic with AC on, it never reaches 100C so the rad is still cooling fine.
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From: Land of mountains, cheese, chocolate and watches
12' W204 C63 AMG coupe "T-Rex", 12' W451 Smart Fortwo Pulse (99' W202 C43 AMG + Ultima Can-Am sold)
My bet is for a hairline crack. Those are the most difficult to find. If the coolant is hot and under pressure, you may see it. Otherwise, have you tried putting some type of sealant around the expansion outlet on the rad side?
Member
Joined: Aug 2013
Posts: 179
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From: Los Angeles
1999 Mercedes Benz C43
Same problem on mine since I got the car a year ago... in 12 months the coolant went low only twice. I'll wait that it gets worse and then I'll replace it and all the hoses.
ANybody has PN for all the coolant hoses?
MBWorld Fanatic!
Joined: Mar 2010
Posts: 5,889
Likes: 323
From: Land of mountains, cheese, chocolate and watches
12' W204 C63 AMG coupe "T-Rex", 12' W451 Smart Fortwo Pulse (99' W202 C43 AMG + Ultima Can-Am sold)
Member
Joined: Aug 2013
Posts: 179
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From: Los Angeles
1999 Mercedes Benz C43
All right, I have an update on my problem. I have a crack at the reservoir so I purchased the 2025000649 Coolant Reservoir New + cap for $41.84 +tax on eBay and arrived all good free shipping ($45.61 total.) (discountbodyparts.com)
Then after lots of searching, I found a shop in North Hollywood (Los Angeles) and they matched all the eBay quotes I had for all the hoses.
Bavarian Parts Motorsports (NOT on eBay)
The upper hose 202 501 59 82 (usually this goes for over $110.) Got it for $45.
The connecting hose 202 501 53 82 to the reservoir got it for $20.
and the hose below (202 500 07 75 MB only) for $65.
I would of purchased the reservoir here too if I had known of this shop, but I had already purchased it on eBay.
Additionally Bavarian Motor Parts in Sun Valley (also on eBay) had these quotes for the hoses.
202 500 07 75 is $60 Special Order MBZ
202 501 53 82 is $21
202 501 59 82 is $59.95
My mechanic will install for $150.
UPDATE:
All done and paid an extra $20. for 1 gal of coolant.
I ask him to inspect the short vacuum line and he replaced it for free also I gave him the Cam Positioning Sensor and did not charged me to install it.
(Actually I made a mistake and wanted to buy the Crank Pos Sensor but anyhow I will have him do that one on Saturday. He said the Cam Pos. Sensor looked pretty sad, so it's good that I have replaced it.)
Then after lots of searching, I found a shop in North Hollywood (Los Angeles) and they matched all the eBay quotes I had for all the hoses.
Bavarian Parts Motorsports (NOT on eBay)
The upper hose 202 501 59 82 (usually this goes for over $110.) Got it for $45.
The connecting hose 202 501 53 82 to the reservoir got it for $20.
and the hose below (202 500 07 75 MB only) for $65.
I would of purchased the reservoir here too if I had known of this shop, but I had already purchased it on eBay.
Additionally Bavarian Motor Parts in Sun Valley (also on eBay) had these quotes for the hoses.
202 500 07 75 is $60 Special Order MBZ
202 501 53 82 is $21
202 501 59 82 is $59.95
My mechanic will install for $150.
UPDATE:
All done and paid an extra $20. for 1 gal of coolant.
I ask him to inspect the short vacuum line and he replaced it for free also I gave him the Cam Positioning Sensor and did not charged me to install it.
(Actually I made a mistake and wanted to buy the Crank Pos Sensor but anyhow I will have him do that one on Saturday. He said the Cam Pos. Sensor looked pretty sad, so it's good that I have replaced it.)
Last edited by venturaexit; Jul 16, 2014 at 09:16 PM. Reason: change
