Stormberg repair - PeachParts Mercedes-Benz Forum

spencerbandit88 · #1 07-18-2004, 01:02 AM

Hello,

I have a 72' Benz 220/8. It has a single Stromberg 175CD carburetor on it. When I was trying to start the engine on it, I couldn't. My friend seems to think that the engine isn't getting gas, and that the carburetor will need to be rebuilt (and yes there is gas in it

)

I was wondering if anyone knew where I could find a sheet to rebuild the carburetor, umm... maybe I would like it to be online, but if not oh well it happens.

And also, do you think that would be the problem, I pulled off the gas line going to the carburetor and there was gas in it, so I think that it's the carburetor.

Thank you for your help and time.

spencerbandit88

Russ114 · #2 07-18-2004, 01:19 AM

according to my local offical Mercedes Benz service agent in brisbane, the stromberg and solex from those era of cars should seek further solice in a nearby garbage bin..

they work well for a few months, but then turn bad!. a holley economaster 280-320 is normally a good worthwhile replacement.

this is going from my personal experience though, it could be different.

nachi11744 · #3 07-18-2004, 11:53 AM

Hello,
You need to look at this webpage for all the info you could ever need for a Stromberg 175CDT/U:www.ruddies.business.t-online.de/se175cdtu.htm.
I do not share the sentiment of the Brisbane MB agent, the Stromberg 175CDT is an excellent carb and the Zenith 35/40INATs are high quality units, the rotten egg is the four barrel Solex 4A1 from the 1970-80s, but even that beast can be made to work with a bit of *patience*.
Have good week

Oreo · #4 07-18-2004, 09:51 PM

I agree with Nachi. I have worked with different Webbers but the Stromberg design is very zen - ie less is more. And very reliable. Start with taking the piston cover off and checking the piston, needle and rubber diaphram.

Oreo

spencerbandit88 · #5 07-19-2004, 12:40 AM

Ok,

I took off the oil resevoir and then the part that it connects to I took off the ruber gasket, should there be any gas in there? Everytime I try and start the engine I don't think that's the engine is getting gas (and again.... there is gas in the tank

)

spencerbandit88

Mark DiSilvestro · #6 07-19-2004, 12:02 PM

Is gas getting pumped to the carb or is there just gas in the line? Get a friend to crank the engine and see if gas actually pumps (for safety, catch it in a container or attach a pressure guage).

You won't see much, if any, gas under the Stromberg topcover and diaphragm. These carbs have a separate float chamber fastened underneath, with an inlet float and valve that could be stuck or clogged. Be sure to correctly align the rubber diaphragm when you reinstall it - there's a little 'tit' on the edge of the diaphragm that fits in a little hole at the rim of the housing.

If fuel IS getting into the float chamber, check the enrichment device. It works like an automatic choke but it's actually a valve that lets extra gas mix in the carb when the engine's cold. It could be sticking too. There's a tiny slot next to the enrichment housing (round part with 2 small coolant hoses attached) through which you may be able to see the mechanism move, otherwise you'll have to remove the enrichment housing for a better look.

Finally, there's an electric fuel cut-off solenoid fastened to the main jet on the bottom of the carburetor. You should hear a click when 12V power is applied.
(I don't remember if power opens it or closes it and there's little mention of the Stromberg eletrical circuit in my W115 manual - perhaps someone else here has more info)

Happy Motoring, Mark

spencerbandit88 · #7 07-19-2004, 11:40 PM

Hello,

This is where I was wondering if there should be fuel at. At the end of the screw driver, in that bowl looking area, there are 2 holes (that I can see)

Mark DiSilvestro · #8 07-19-2004, 11:57 PM

That's the main jet needle and variable venturi piston/diaphragm assembly. You shouldn't see any raw gas there, though if the engine was running and you were looking down the air intake/carburettor throat you might see some fuel spray. The main jet adjustment and float chamber where the gas should be (and where you could see the gas, if there was a glass window on the side like some Japanese carburettors) are on the BOTTOM of the carburettor.

Happy Motoring, Mark

Mark DiSilvestro · #9 07-20-2004, 08:53 AM

Have you had the car running recently or has it been sitting a long time?
If you pull that diaphragm and piston assy staight up and out and examine the tip of the metering needle (be careful not to bend it!) you should see some gas. If it's dry or there's some crud instead, you'll have to go deeper. Also examine the rubber diaphragm. If it's hard or there are any holes or tears, it needs replacement. Remember to reinstall that diaphragm back in the same position - it has a little 'tit' that locates the direction.

Happy Motoring, Mark

#10 07-20-2004, 01:08 PM

Also too, unscrew the water choke from the housing (the front part that bolts onto the body that has the RICH written on it) and you'll see a small brass piston in the right side of it (either exposed or covered with a rubber protector) it is struck by a little hammer that is regulated by the coolant temperature and that's why there are cooland lines leading to the choke. Make sure the little brass pisotn can move up and down freely with some spring tension, if not, try loosening it up with some WD40. This is what passes for a choke on that carb, the piston regulates how much gas gets to the carb and if ceased or stuck will either give the car too little or too much gas.

I had headaches up and down with my Stromberg until I got a used carb, took it apart and compared the two. I found that this little piston is supposed to have a spring in the bottom of the chamber to give the piston tension and mine had no spring. Once the spring was installed, no more problems.

Good Luck,

AARON ROCHARD

1976 230.4 W115

Oreo · #11 07-21-2004, 01:35 AM

Hi Spencer

The fuel comes out from where the needle enters the jet. That bass hole is the jet and the needle moving in and out meters the fuel - hence "viariable jet". If the needle and piston are moving freely then that's all there is to it. Like Mark said definitely check for fuel at the bottom of the jet hole ie the fuel bowl. Put a toothpick in and see if its wet.

The car should at least fire up when you step on the gas if there fuel in the bowl. Idling, driveability etc, is another isssue

Oreo

spencerbandit88 · #12 07-21-2004, 01:51 AM

Hello,

Again to say I tried to start it. It turns over great. But still won't start

I tried it with the gas all the way down and with out the gas down. But nothing, I know there is a spark. Oh also I didn't see the window on the bottom, I looked the best I could without taking the carburetor off. Also I took off the choke parts and there were some fuel lines that had some build up in it.

spencerbandit88

Oreo · #13 07-21-2004, 04:43 AM

Hi Spencer

Did you confirm if the fuel pump is working and if there is gas in the carb? If you say there's spark, sure sounds like there's no fuel then. You only need fuel and spark to get some life.

There is no window on the bowl, I'm sure. Other then opening it up, there is no other way to tell if there's fuel in the bowl except thru the jet hole. In my experience from a completely dry bowl, it takes about 5 -10 secs of cranking to get it started.

You mentioned "build up" - is this blocking the bowl needle valve? Try blowing thru it?

What is the history of this car that led to it not starting?

Oreo

cth350 · #14 07-21-2004, 07:34 AM

Sounds like it wouldn't hurt for you to get the M115 engine manual. It shows up on ebay often. -CTH

Mark DiSilvestro · #15 07-21-2004, 09:54 AM

There is no window on the Stromberg. As I said, IF you had one, you could see the gas. It's almost exclusively a feature of Japanese carburettors. Have you tried a bit of gas or starting fluid down the carburettor throat? Sounds like, at best, you're getting gas to the carb but there's a blockage at the inlet pipe or valve.

Happy Motoring, Mark