I've recently came into possession of a one owner 1975 450 SEL (W116 I believe). It has 35,000 miles on it and in great condition in appearance. It also has a very interesting history.
My best guess is it was garage parked sometime before 2011 with a 1/4 tank of gasoline still in it.
Almost all of the gas has evaporated so what was left had the consistency of syrup and the worst bad gas smell I've experienced. Gas tank is now clean, fuel pump and fuel gauge sending unit were both beyond repair which is where my problems started.
I am a retired mechanic but I've never touched a Mercedes much less worked on one. I understand all hoses, belts, fuel lines, and vacuum hoses will need replacing. I finally gave up finding the exact fuel pump and settled on a Bosh with the same specs but a different output direction. Straight out instead of 90 (degrees) Still haven't found the exact tank sending unit at all.
Is replacing these items with exact cloth covered hoses and clamps, smooth rubber hoses, silicone hoses, ect necessary to maintain the cars originality?
The car came with Blue Velour carpet and seats having very large blue corduroy style upholstery material. I cant seem to find this anywhere in a 1975 Mercedes at all, I did see it in a few early 80s pictures. On the back seat the padding has turned to dust and the cloth was perfect till I sat in it and it was like tissue paper and now destroyed, front seats are perfect. Called the local Mercedes and they said I couldn't get them or the material to recover them, and replacement with leather would be the best option. Due to it's history I'd really like to finish this car as it was delivered. I'm about ready to start ordering parts if I can find them.
I joined benzworld.org yesterday and was told W116.org was the best place for me to get the information needed on this W116. I did get a nice recommendation on a book on how to tune the Kjet fuel injection system today. Hopefully the fuel system won't give me too much trouble when I get to that point. Well, I had several pictures to add but it appears they are too large.
Any help would be greatly appreciated
Johnny
Hello welcome ,
I think that you have D-jetronic fuel injection on your car based on the year 1975 and the fuel pump with the 90 degrees outlet you discribe , resize your pics to a smaller size and try again to insert them in to your post , you have Pullman velour interior the best looking interior to have in a W116 (in my opinion)
Greetings:John
Blue velours:
https://25.media.tumblr.com/tumblr_mdwb03oxhE1r37rcwo1_500.jpg
I think the fabric is currently not available, but is being remade in the next year or so.
Were all pretty good here about finding parts, Let us know what you are looking for.
https://www.w116.org/library/
on the right side is seat materials catalog.
Hallo and welcome!
What a great car you have - a one owner low mileage is not common these days.
I also believe your car has d-jet. I replaced the entire k-jet fuel assembly 1-2 years ago. All parts readily available.
I bought good quality fuel hoses, some original MB, and some had an inner coating that made them resistant to ethanol.
Velour is fantastic. Too bad you need to replace it with leather.
Please add some pic!
https://www.ebay.com/itm/224972029144?epid=18053828280&hash=item346160bcd8:g:pb8AAOSwRUlic2Sn
Fuel sender.
IMG_0228.jpgIMG_0229.jpgIMG_0231.jpgIMG_0234.jpg
Thank you all for responding this.
Sorry about the duplication on the pics not sure how I did that.
RUMB: I might be adding more work than necessary looking for the exact part number? My tank sender is a two piece using a separate nut to secure it in the tank and a different part number on the sender itself. 21/302 817/10/1 3 83
This unit would save me quite a lot of money if it'll work?
johnnyw116 and Jan S: I'm not sure how to distinguish between the K-jet and D-jet yet, but I'm adding a pic of the engine and hopefully you can tell.
IMG_0237.jpg
Djet
daantjie: Thank you
Lovely car! I'm sorting out the DJet on my 75 as well.
That rear seat will be your biggest headache unfortunately. There is this set (https://www.ebay.com/itm/115387508564) on ebay in Germany that you may want to consider. The cover is ratty but it could be a matching stopgap until the material is available again. The bigger thing is that it looks to have good seat springs. If yours are rusted away, buying a good used set from Europe is the best current option because these cars are very thin on the ground in wrecking yards and such. You might also need to buy new rear seat pads. I believe cabrio.de was the best place to get them but I think GAHH might also carry them. I was very lucky to find a parts car with immaculate rear seat frames and pads that I transferred into mine.
Definitely Djet. I believe if manufactured after June/July the first of the Kjet came out. Mine is a Djet (March 1975).
Quote from: Pete49 on 05 July 2022, 10:01 PMDefinitely Djet. I believe if manufactured after June/July the first of the Kjet came out. Mine is a Djet (March 1975).
I believe the same that mid/late 1975 the k-jetronic came in , and around that date also the first 6.9 came out and i also think that the 6.9 was the first k-jetronic equipped W116 , i owned in the past an 1975 450SE with k-jetronic but i cant remember from which month it was
I did buy a used tank sending unit on eBay which should arrive by the end of the month, and with that I'll be ready to replace the fuel tank back in the car. The new fuel pump came with two check valves one I'm assuming to be mounted on the pressure side of the pump but I've found no check valves in the old pump assembly unless there is a check valve inside the old pump?
On the third pic I'm including, this was mounted between the suction side of the fuel pump and the fuel tank. Does anyone know what it is, and what it does? Is this something that must be replaced or just a good cleaning and paint?
Yes the old pump has the valve inside that opens up at 3 Bar towards the fuel filter, and on the third pic that is an fuel damper it has some sort of noise reducing fuction ? a cleanup and some paint will do , i had recent the same problem that i could not find the original d-jetronic fuel pump (mine was leaking) so i used an Nissan 17011-P7211 fuel pump these are identical to our old NLA D-jetronic fuel pumps .
You can put your fuel tank back and install the sender unit later iff you want becouse you have acces to the fuel sender unit when you take the first aid kit out
That is a damper within the fuel system functioning I believe to absorb the fuel pulsating
as a result of the pump function thus evening out the system pressure.
Great,
Then I can clean up the dampener, and I will recheck the pump specs I purchased to verify it has a check valve and if not I'll need a inline check valve that opens at 3 bar.
This is the knowledge that without, would cause issues later on in this project.
Thank you very much
Johnny
Be sure that you use an 3bar fuel pump the D-jetronic injection system works with an lower pressure than the k-jetronic injection system , the k-jetronic fuel pumps are around 6/7 Bar
Hi all,
I have done some more broad reading with regard to the fuel system and was surprised to come upon the suggestion that the pressure put out by the pump is somewhat irrelevant, only becoming an issue if there should be a blockage in the return side. Perhaps someone on here would like to comment.
Regards,
Bill
They say that with an pump with more pressure it will run but the on the longer term the fuel pressure regulator goes defect and it is also bad for the injectors
https://jetronic.org/en/d-jetronic/fuel-pump
Well the pump I purchased is a Bosh 45699FF its a turbine pump with little to no pulsing, and because it came with two external check valves I must assume there is not a internal valve. One of these allows for a banjo fitting so I'll try to find one to adapt to the hose. I'll have to research this pump on its output pressure.
you only need the checkvalve for the banjo fitting to connect the pump to the fuel filter ,and you dont need the other checkvalve , the check valve is just only an one way valve for preventing the backflow of fuel and it also holds the fuel pressure , so now you need the banjo and the bolt for it
Fuel Line Banjo Bolt 80810600
Fuel Pump to Fuel Filter with 2 Banjo Fittings 1234700675
MB 001-091-71-01 is the pump with the prepared fittings kit that you will receive if purchased from MB
The pressure damper on your third pic is a cavity, i.e empty space. A thorough clean is sufficient, especially inside. I believe it's fairly corrosion resistant. Let it soak a day or two and use a brush, compressed air, etc. If inside looks really bad this is also a good case to test out a ultrasonic washer.
My understanding is that the pressure damper reduces pulsation on the suction side of the pump, i.e. makes sure the flow to the pump inlet is steady/even/stable?
I renewed the fuel assembly (k-jet) a while back (se pic). The frame, the holder for the tank hose and the pressure damper I cleaned - all the rest is new.
I also installed an extra pre-filter between tank strainer and pump inlet (at the top in pic) to avoid "larger" particles entering the pump. Works fine so far.
Update:
Well, I think I've got all of the fuel system lines, hoses, and tank sending unit ordered. Most of the engine crankcase breather and air pump hoses, and engine cooling system hoses ordered. These will start coming in next week through the middle of August.
Hopefully I'll be able to start the engine next week and verify what if anything is needed on the injection/ ignition system.
I've only started researching the vacuum system and looking at the actual vacuum lines, switches, and reservoirs on the car. The small colored vacuum lines appear to still be flexible and in good condition, all of the small black rubber lines will need replacement. This is really impressive what all they have done with vacuum, I just hope it all works when I get it running. I've worked with vacuum in the past but not on anything quite this complex.
Johnny
Pushed it outside till the parts start coming in, and took a little better pics outside.