71' 280 SL Running very rich (New to the site)

[GTI_VR6]

Hello,

First of all i would like to introduce myself as im new to this website and like to apologize for any topics that may have been posted over and over again. I have been doing some research on my particular problem but im running into a dead end so i figured i would post my issue and hopefully someone with wise knowledge could contribute to my issue. As the topic states i have a 1971' 280SL and its just running very rich lately. Some symptoms i have noticed is that it misfires constantly, runs very rich and tons of black smoke coming out of the exhaust....i have adjusted the sloted screw at the throttle body so spec and also have adjusted the injection rod linkage to spec. I have tested the cold start valve and does it not have a internal nor external leak.....im not sure what else to check for, i don't even know if im on the right track but hopefully someone can chime in on this.....thanks in advance...cheers  

PS. Did i mention it backfires and guzzles gas like a V12 LOL......

[glenn]

Have you adjusted the valves?

[GTI_VR6]

No i have not gone to that extent just yet, i figured to check the timing out beforehand,we're going back Mechanics 101 LOL

[glenn]

And a compression test? 
You don't want burnt valves.....

[ja17]

Hello,

Make sure that the Warm Running Device (WRD) on the injection pump is not stuck. What is the history of thisrich running  problem?

[GTI_VR6]

Well the vehicle does not get driven too much, only on sunny days for short trips around town etc....when i pulled it out of storage this year i noticed it running very rich but i thought to myself maybe its just carbon build up and needs to be driven but the problem persisted. I will check timing first of all then everything else.......what is the WRD device? Where can i locate it, whats it look like and most important how do i check it for functionality....? Thanks in advance

[jeffc280sl]

Do a search on WRD and you will find a wealth of info.  It is located ontop of the fip.  It has an inlet and outlet hot water line to warm a plunger device.  There is a small air filter on the back end of the fip.  After the engine is warm no air should be sucked through this air filter.  The easiest way to test it is to unscrew the air filter to see if air is sucking after the engine is warm.

[Doubleclutch]

Thanks for starting this thread. I'm new also and am trying to straighten out a 71 that came to me with a rich run problem. I will try the WRD test before attempting the FI adjustments.