1966 230SL Fuel Filter

[Harry]

So I'm curious about fuel filters for this car.  As some already know, I recently did some extensive work on the rear end of the car, including removal of the fuel tank.  When I reinstalled the tank and ran the line from the tank to the electric fuel pump, I installed an in-filter.  Previous, there was not a filter to protect the (very expensive) fuel pump.

Have others installed a filter here as well?  If not, why not?

Thanks,
Harry

[mbzse]

Previous, there was not a filter to protect the (very expensive) fuel pump

There are two, actually. One in the "flower pot" of the fuel tank (inside it), one on the inlet fitting of the electric fuel feed pump.
Only fine mesh filters, though.
A fine grain paper fuel filter (protecting the injection pump) is attached onto the left engine support. Renew this one once in a while, BTW!

[Harry]

Thanks very much!

[rgafitanu@gmail.com]

I did and I have to advise against it. My tank is continuously shedding rust (or some other black dust) to the extent that I have now a permanently plumbed fuel pressure gauge and a spare fuel pump to replace every 1000 miles when the fuel pump internal screen clogs up and stalls the engine. I placed a glass filter before the pump hoping that the clogging will be visible and the filter easier to change. After 2 miles the glass filter clogged and stalled the engine. As a matter of fact it did it's job, it prevented the dust from getting further. I would have to try filters with higher porosity but lower than the pump's screen to make it work and not change it every 2 miles. So I gave up, when the fuel pressure drops to 6 PSI it's time to lift the car and swap the pump.

[ja17]

Normally the filters and screens already in the system are adequate. If you add a pre-filter, before the electric pump, make sure it is large enough to handle the high volume of fuel. Notice that the line from the tank is fairly large diameter, try not to reduce the diameter much with the fuel filter,  or fuel volume and fuel pressure will suffer. I suggest flushing the tank first, cleaning the screens, then using a large filter canister like those used on the later SLs (W107 etc)or similar. Those little glass fuel filters are just too small.

[114015]

 

Tank tour - nothing else !!   

I am happy that Joe already jumped in with his very kind and extremely helpful hints here - as usual.
Thanks a lot, Joe.

However, I have to be a bit more harsh with you, Radu !

I would have to try filters with higher porosity but lower than the pump's screen to make it work and not change it every 2 miles.

Sorry about this but this is serious nonsense ... filters with higher porosity.

If you have that much of debris, rust  and coffee grounds in your tank
then the ONLY way to go is not using more filters but

clean out your tank first !

There have been many threads here regarding this absolutely essential task.

Go search the forum:

e.g. here:
https://www.sl113.org/forums/index.php?topic=1712.0
or here:
https://www.sl113.org/forums/index.php?action=search2
or here:
https://www.sl113.org/forums/index.php?topic=21147.msg150478#msg150478

... and do your homework first.

Tank rust is a very common gremlin here with our cars, about every 2nd owner has experienced that in the past.
There is only one help:
Clean out your tank thoroughly 
and get it sealed, etc.
or get a new tank - your choice.

But remove the cause of your problems first before you try to fix a problem with another problem.

Ask me how I know ....


Achim
(removed about 2 kilograms of tank debris during the tank tour)

[Mike K]

I did and I have to advise against it. My tank is continuously shedding rust (or some other black dust) to the extent that I have now a permanently plumbed fuel pressure gauge and a spare fuel pump to replace every 1000 miles when the fuel pump internal screen clogs up and stalls the engine. I placed a glass filter before the pump hoping that the clogging will be visible and the filter easier to change. After 2 miles the glass filter clogged and stalled the engine. As a matter of fact it did it's job, it prevented the dust from getting further. I would have to try filters with higher porosity but lower than the pump's screen to make it work and not change it every 2 miles. So I gave up, when the fuel pressure drops to 6 PSI it's time to lift the car and swap the pump.

Does it not make sense to invest in a new tank, instead of going through all of this? I had similar issues when I first bought my car, and it was all cleared up by replacing the tank.  The replacement fuel tanks have actually come down in price to around €400-/$450-
http://www.mbclassics.de/index.php?a=5874&lang=eng

When I replaced mine 3 years ago it was closer to  €1, 000-

Best,
Mike

[mbpaul]

The tank in my 230SL was cleaned and sealed a few times, some by me and some by professionals.  Nothing really helped.  I finally paid around $1000 for a new tank and I could not believe the difference.  Should have done it sooner.

No experience myself with the repro tanks but others on this forum have not reported good things:

https://www.sl113.org/forums/index.php?topic=25256.0

[Benz Dr.]

The 65 liter tank would be an original and it's the 82 liter tank that's been reproduced.

[mbpaul]

SLS says they have a repro 65 l tank.  But the tank I put in was a $1000 or so MB Classic part, not a repro. 

[Mike K]

Based on my experience, it's a no brainer to have the tank replaced once it starts "disintegrating" from the inside....
http://www.sl113.org/forums/index.php?topic=19421.msg136515#msg136515

SLS 65L repro tank: http://www.sls-hh-shop.de/en/230-280SL-W113/47-Fuel-Tank/Fuel-Tank-65-litre-Repro-Fuel-Tank-65-litre-Repro.html

SLS 82L tank: http://www.sls-hh-shop.de/en/230-280SL-W113/47-Fuel-Tank/Fuel-tank-82ltr-230SL-late-250-280SL-Fuel-tank-82ltr-230SL-late-250-280SL.html

[rgafitanu@gmail.com]

To answer to you Achim.
I did clean the tank a dozen times with a lot of solutions.
The reason I am playing with filters is the high cost of a new tank. As you can see I have an SE, MB Classic Center quoted me $1200 and I am trying to get some discounts from them but it looks like a new tank would be my Christmas present this year. I did not intend to leave the situation like this but only to extend it until I get a new tank. I was playing with filters to make my: up-on-the-lift, remove-pump, attach-spare-pump, pull-clogged-screen, clean-screen, wait-for-next easier. Although I don't go to work with it I am driving this car daily and I love it.
On the other hand I was hoping that at some point the tank may run out of this rust dust considering that now it is being filled consistently to the top (I know it doesn't make much sense).
I wouldn't want to seal it due to the many posts here, nor could I find a good tank sealer in New England.
EBay.de appears to have new tank for about 600 euros but I don't know if they are reproductions or not.
I just saw, did your really remove 2 Kg of rust from a tank? That means it will never end. I guess it's clear what my Christmas present it.

[Benz Dr.]

SLS says they have a repro 65 l tank.  But the tank I put in was a $1000 or so MB Classic part, not a repro.

OK, then that's become available. There was a time when only the large tank was repro.