Fueltank

[weradus]

Hi,

Last long weekend I toolk the 230SL for its first spin and all went (almost) well.  When the tank reaches 2/4 (half full) and beyond after every so many miles the car has problems and holds-back and loses power. Stopping the car, turning ignition off makes the problem goes away for some time/miles. People told me this may have to do with a clogged filter as a result of rust in my fuel tank. Any of you guys on the forum who noticed similair behaviour and what has been done to resolve it ?

Cheers, Willem.

[AGT]

Willem

I had the same problem last weekend  - see my post below about fuel starvation. I have not been back out to France to begin checking the filters but that looks like the first thing to do.

Best regards
Andrew

1966 230SL

[mdsalemi]

Willem,

I had the same problem about 5 years ago.  Aside from the fuel issue itself in your 40+ year old tank, don't forget to check the integrity of the wiring to the fuel pump itself.

I did all the normal things--cleaning filters, changing filters, blowing out lines.  An independent mechanic locally said change the tank.  It was expensive but did the trick.  After all these years the inside of the tank was slowing rusting away with microscopic rust particles.

You'll get the advice here from others--go through all the fuel system (lines, filters) except the tank first; if the problem returns, you might need a new tank.

[weradus]

Hi,

The filter(s) was changed  as part of the first things todo. Don't think there is a problem with wiring 'cause I can hear the fuel pump once the engine has stopped. I do see a lot of rust on the inside of the fueltank cap. Sofar engine has started without a problem after a minute or so of rest.

New fueltanks seem expensive when purchased at the local dealer ~ 1000 euro .....

[Naj ✝︎]

Hi,

You can take off the fuel sender unit and have a look inside the tank to see what state it is in.
Take care -  you're playing with fuel and fumes!

Also. more info on the tank in the tech manual:

http://www.sl113.org/wiki/Fuel/Tank

Naj

P.S: Preorder a new cork sealing gasket for the sender unit.

[mdsalemi]

Hi,

The filter(s) was changed  as part of the first things todo. Don't think there is a problem with wiring 'cause I can hear the fuel pump once the engine has stopped. I do see a lot of rust on the inside of the fueltank cap. Sofar engine has started without a problem after a minute or so of rest.

New fueltanks seem expensive when purchased at the local dealer ~ 1000 euro .....

Willem, and Naj--

I can only relate to you my own, direct experience which I have lived with; suffered with; and eventually solved.

1)  The electrical wiring problem I had was intermittent.  Just because you hear a sound of a pump "whirring" does not mean you have the proper voltage to the pump.  I had a bad connection that worked most times, but did not at other times.  The only solution was removal of the pump to discover this problem (overlooked by every mechanic who ever worked on my car, but me ) and then making a new wiring from the harness in the trunk (boot) to the pump--after ensuring that the connectors were soldered in addition to crimped.  You need to check each connection, each point on the harness and where the wires connect to the pump.  A small voltage drop will cause the pump to produce less pressure and volume; bad connections or dirty connections cause either intermittent operation or a voltage drop.

2)  Yes, the tanks are expensive--quite expensive.  So is living with a problem tank (if that is the problem) and enduring the awful uncertainty of not knowing if you will ever get to where you are going without a tow, or even getting stranded somewhere remote.

The mechanic who told me about my tank told me that it was rusting on the inside, but nearly-microscopic pinholes in the galvanized coating.  Not unexpected after 40+ years.  He had run into the same issue on several local Pagodas (and had a small pile of 40 year old fuel tanks waiting to be picked up by the scrap dealer as proof) and changing of the tanks cleared up a LOT of problems.

This was just MY experience; yours may be different.  There are some owners here who "Re-NU" their tanks, for some this caused more problems or just bought time.

You have to make your own decisions based upon your time, your wherewithal, and how much $$$ (or €€€) you have--along with your tolerance for the uncertain.  I just tell you what happened to me, as my problems were real, and were eventually solved.  New wiring and a new fuel tank solved mine.

[weradus]

thanks for sharing your experience .... i found Tank82ltr,230SLlate 250-280SL for halve the price , any of you has experience with it ?

[glenn]

Depending on your level of affluence......  Installing a new one takes about as much time as installing a cleaned old one.  So, it is $750 vs. the time to clean a dirty one.   (If you were in NC, USA, I'd clean it for $500.  You Dutch have a reputation to uphold!!))  Take it out, (keep in mind SAFETY) vacuum it, turn it upside down, shake it, vacuum, repeat. .. ..  You've got to get the crud out of the plastic quart.  The crud blocks the gas in the corners of the square where the FIP return line(10 mm dia?) tangentially enters the plastic.   Clean, replace? all the filters(3 at least?) in the gas lines.  Should be good for a lot of years. ..    

[Jordan]

Willem, I had the very same issue with mine when I bought it.  It tended to die on inclines but I would let it sit and then it would start again.  Turned out I had a very dirty fuel tank, about 3cm of rust and crud on the bottom.  It was so bad the hole in the side of the flower pot at the bottom of the tank was completely plugged so it would run out of fuel as soon as the fuel level in the tank dropped below the top of the flower pot.  I ended up putting in a new tank.  I have never had the problem again.  Make sure you check the filter in the electric fuel pump as well.  Also check all the fuel lines to make sure you don't have a partial obstruction somewhere.

[mdsalemi]

thanks for sharing your experience .... i found Tank82ltr,230SLlate 250-280SL for halve the price , any of you has experience with it ?

Willem, my guess is that this reproduction tank that SLS is selling is probably from the same source as the reproduction tank sold by K&K in the USA.  You might try calling them and see if they have a return policy or can refer you to a customer who bought and installed it.

The best kind of advertising is a happy customer, so SLS and or K&K should be able to tell you who might have installed a reproduction tank and how well it worked for them.  I know that years ago, K&K was working on these with a supplier in Poland and the first batch came in with the filler neck a bit incorrect.  I think that was years ago and was long ago corrected.  But, worth a call.

[weradus]

Guys, I went for an original Mercedes tank and had it installed this week. Hopefully it resolves my issue ....

[franjo_66]

Guys

Just for reference, I bought the 82 litre tank for my 230SL a few months ago and the fit was perfect. No issues and installation was very straightforward

Regards
Franjo

[Garry]

Franjo,

Just as a matter of interest, where did you get the larger takn from and what sort of dollars was it if I may ask?

Garry