Author Topic: WRD question  (Read 3386 times)

igor111

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WRD question
« on: June 11, 2009, 07:34:42 »
Hello,
I've been reading this forum much and it's been very helpfull to me. I have a w111 220 SE copue with a two plunger fuel injection pump, but it has the same WRD as early 230 pagoda, so I supose someone could know some answers. Recently I did a linkage tour, dwell angle is 40 degrees, distributor is at 6 degrees BTDC at idling and arround 28 at 3000 rpm.  I suppose that's all ok.
Now the problem - my WRD thermostat wasn't working properly (unfortunately it'a a expencive one), so I put another one (not new, but I made some boiling water tests and it seems that it's working properly). When I pulled down my WRD from the pump, I made the following test: I removed the colling water thermostat and pushed the plunger with my finger to the end. Then I put a finger on a connection for idle adjusting screw hose and blowed some air with my mouth through the hole for air filter and it dosen't leak at all. My WRD also has a stop screw if you want to disengage it, and when I do that, the air also doesn't leak. Then I measured the movement of themrostat pin, and when it is fully extended, the air also doesn't leak, so in my opinion WRD works properly.
When I start up the cold engine, it fires up great (in a second), and idle is at 1100 rpm, and it's working excellent. Gradually, as it warms up, it comes to 800 rpm and works great, BUT when i remove the air filter from WRD i can still fell some air suction, and if close it with my finger, nothing happens, rpm dosen't change. Since everything else works normal, should I be worried about that? It is sucking air even if I disengage with the stop screw.
My venturi plate is fully closed at idling (not binding), and I did some renewal so it dosen't have any play, but I didn't put new plate, so when it is fully closed I can fell air suction if I put my hand in front of it. I suppose there shouldn't be air suction at all?

Sorry for my english and long question :) and thanks!!!

ja17

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Re: WRD question
« Reply #1 on: June 11, 2009, 11:18:11 »
Hello Igor,

It sounds like everything is working as it should.  a slight amount of suction and noise is normal at the venturi.   Your idle is a bit high but this may be just a minor adjustment of the idle mixture screw on the injection pump and then slightly closing the air idle screw.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

igor111

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Re: WRD question
« Reply #2 on: June 11, 2009, 20:16:49 »
Thanks for answer Joe, I should leave it as it is then. Since my car is equiped with Behr A/C system, I found out by experimenting that 800 rpm is about right because idle drops a bit when the compresor is engaged. Since it's an early version, it doesn't have AC solenoid.

Thanks again!