Looking at a 74 280
 

I am looking at a 74 280. It looks good but needs some carb work. Looking at other threads that seems to be the achilles heel on these models. just how troublesome are the carbs on these? With a kit can I expect to be able to rebuild it myself? In the 80s I have rebuilt a few quadrajets with success 50% of the time. If not, is there a good aftermarket replacement?

It is to be a daily driver, not a show piece.

http://cgi.ebay.com/ebaymotors/Mercedes-Benz-200-Series-114-1974-Mercedes-280-4-Door-Sedan-Clean-NICE_W0QQitemZ300084062490QQihZ020QQcategoryZ6329QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

The 4A1 is basically unstable. Chuck Taylor and others have successfully replaced it with a quadrajet. Rebuilding is straight forward. Watch for warped and broken parts.

Chuck used a Holley 4360c carb. (The c is for integral choke).

-CTH

What do you mean by unstable? What can I expect if I get one as a daily driver? Will it strand me? Will it just flood easy?

Yeah,if the carb is worn out it can strand you. It can also burn down the car. It can flood the plugs with no warning. It can also run so lean it'll fry the valves.

If it is in good shape they aren't bad carbs. They're just Quadrajets manufactured under an European license. MB got a little too creative with idle compensators and a couple of other features.

Generally the problem with them is they have been abused when rebuilt. Instead of using the proper torque settings people just crank the screws tighter. Same problem with the old Quadrajets on American iron.

Once they're tweaked, they're tweaked! If they aren't too bad and with the proper amount of patience and care the sealing surfaces can be brought back to a reasonably "flat" surface.

I fought mine for three weeks and finally conceded. Too many monkeys using screwdrivers for me to restore.

I adapted a Quad, a Motorcraft two barrel, a Carter two barrel (which I've been running for 6 months) and I am in the process of converting over to a TBI using the Megasquirt ECU.

PLEASE keep us updated on your progress!!!! Please!
Thanks :D

Funny, I just collected all the parts to do the exact same thing for a 250 lwb that the PO switched to an Edelbrock (the euro M123 motor is 2.5l and uses essentially same 4A1 carb).

I was going to use the original chevy 2.8 computer first to see how it goes.

-CTH

Could I put on the djet system from my 73 450SE parts car?

NO

Happy Motoring, Mark

Same here, that sounds like a good upgrade if it works...don't you think it'll need new cams to get the most out of it?

Wonder what model Edelbrock Q-jet carb is the equivalent.

If you felt like...
- Modifying the intake manifold and/or heads for the injectors and MAP sensor
- Modifying the distributor to accept trigger points
- Found a way to get the trigger points to fire a sequence for a 6-cyl engine rather than a 4/8 cyl one

Basically, it is possible with a lot of work, modifying and time. But I'd suggest MegaSquirt before D-Jet. Now if you can find one that came with its OWN D-Jet... Keep in mind, each D-Jet ECU is made for the engine it was originally put on. A 3.5 ECU has a different volumetric curve built in than a 4.5's, and I'm sure a 4.5's ECU would have a way different volumetric calculation than an m110 would need...

The M114E and M110E motors were EFI equipped 6 cylinders. I have one of each waiting for a suitable car to put them in.

-CTH

Ken

You can drop that 350 from your roadmaster into it and scare the crap out of many M-100 owners :-).

All the best

I wouldnt want it to be faster than my 6.9 now, would I?

some years back i converted a bmw 3.0 liter to a q jet. i found that the jets for a '67 pontiac sprint worked very well. (it was a straight six ohc engine). it sounds counterintuitive but the jets you want are the most rich (the sprint ones). the smaller engine doesn't have as much vacuum to pull and the richer jets will provide the correct mixture.

good luck.

if converting a mb six i would use the edelbrock q jet replacement carb.

tom w