Pagoda SL Group

W113 Pagoda SL Group => Drive train, fuel, suspension, steering & brakes => Topic started by: Charles 230SL on March 10, 2015, 14:57:25

Title: 230SL expansion tank
Post by: Charles 230SL on March 10, 2015, 14:57:25
hello, my brass expansion tank is leaking and I've soldered it several times over the past 9 months;  yet it continues to leak.. I'm thinking about replacing it with one I found on eBay:
http://www.ebay.com/itm/Mercedes-Benz-230SL-250SL-280SL-BEHR-OEM-Compensation-Tank-1135000149-/261806757603#ht_3312wt_1362.

Before I do, I thought I'd get you guys' thoughts on it. The seller claims this tank is "NOS" but it appears to be in rough shape.  I think 1967 was the last year for these pancake tanks; is it feasible the tank has been on a shelf for 45+ years without being in service?  Does the price seem reasonable?  thanks, Charles
Title: Re: 230SL expansion tank
Post by: dirtrack49 on March 10, 2015, 15:12:53
Hi Charles,

I would give JB Weld a try first. You can get it in the regular formula, or they also have it for water tanks. Used it on the bracket tang on my expansion tank and so far so good.

Don't really know if that is a good price or not. For these cars, I would say that might be reasonable. Being NOS it looks pretty good to me.
Title: Re: 230SL expansion tank
Post by: Charles 230SL on March 10, 2015, 16:14:19
I swear by JB Weld and thats a good idea for the bracket -  but it might not work for the tank itself.
I noticed that over a period of time, the places I soldered began to crack (and leak) due to repeated expansion.  I think after 50+ years of expanding/contracting the brass has finally fatigued.

Title: Re: 230SL expansion tank
Post by: kampala on March 10, 2015, 17:14:49
You should confirm with Mercedes Classics Center as I thought this tank was still avail new from Mercedes.  With the discounts (not list) your cost may be in the low to mid $300.
Title: Re: 230SL expansion tank
Post by: badali on March 10, 2015, 20:54:28
This tank has been on ebay for a long time.  It looks used to me.  There is green tarnish where the cap goes.  The bracket is missing from the bottom.  I found one on ebay for $50 in better condition.  The tank he is selling may be ok but the price seems high.  Since he has had it for sale for so long send him a message and see if he'll take less...
Title: Re: 230SL expansion tank
Post by: scoot on March 10, 2015, 22:31:19
You should confirm with Mercedes Classics Center as I thought this tank was still avail new from Mercedes.  With the discounts (not list) your cost may be in the low to mid $300.
MSRP price for the tank from MB is $434.  Discount on-line dealer price (mymercedesparts.com for example) is $338.  That DOESN'T mean it is available but if it is, those are the prices.   Classic center price will be in between the two most likely.
Title: Re: 230SL expansion tank
Post by: Charles 230SL on March 11, 2015, 19:07:39
Got it,,,,thanks all
Title: Re: 230SL expansion tank
Post by: dirtrack49 on March 12, 2015, 02:56:09
Charles,

Just remembered something else I used JB Weld on many years ago which may make you rethink using it on the expansion tank.

Had a swimming pool pump intake tank split in several directions from a weeks worth of just above zero temperatures. Could not find a replacement without buying the entire pump and filter system. So... as a last resort, I JB Welded the fool thing in who knows how many places. It was still holding water and pressure five years later when I moved to a new location. And this was just your normal JB Weld. I bet if you used the one made for water tanks, that expansion tank will last another 40+ years.
Title: Re: 230SL expansion tank
Post by: Charles 230SL on March 12, 2015, 14:33:06
thanks Tom, I'll let you know how it goes.
Title: Re: 230SL expansion tank
Post by: J. Huber on March 12, 2015, 15:25:22
A few years back I had two issues with my expansion tank: the bracket had come loose and there developed a minute hole in the tank. Many suggested JBW -- and I too had used that on a pool pump/heater problem. Good stuff. However, I also heard better advice -- take it to a radiator place who can braze? it and fix it right. I actually shipped mine to Dave Gallon, who knew a guy...(of course)

Came back good as new -- although I decided to primer and paint it to get the proper look.
Title: Re: 230SL expansion tank
Post by: Charles 230SL on March 16, 2015, 01:37:52
I tried brazing after my first solder attempt failed.  Unfortunately, brazing just took too much heat (at least for my skill-set).  I had to go back and re-solder the bracket, the seam, and even the neck/overpress tube melted loose. 

I asked Tom Hanson whether the Classic Center had a brass tank available and he said that the early coolant tank hasn't been around in decades.

After pondering for another day or two, and being reassured (again) from the seller that the coolant tank was indeed 'NOS', I went ahead and bought the one on eBay:
http://www.ebay.com/itm/Mercedes-Benz-230SL-250SL-280SL-BEHR-OEM-Compensation-Tank-1135000149-/261806757603#ht_3312wt_1362.

It'll be here tomorrow. Thanks all, Charles
Title: Re: 230SL expansion tank
Post by: Charles 230SL on April 08, 2015, 02:11:31
The coolant tank arrived and as advertised, was definitely new-old-stock.  It cleaned up very nicely and looks great installed.  I noticed that the original tank has a serial number stamped on the top, whereas this new tank has no serial number. I wonder why..
Title: Re: 230SL expansion tank
Post by: ja17 on April 08, 2015, 05:05:36


For solder repairs on structural areas, use a solder with a higher tin content for strength. Normal solder is 50 percent tin and 50 percent lead.   Try at least a 70 percent tin mix for problem areas.