extra part in WRD

[Ron]

Now that my car is running, I'm trying to make it run well.  It's the usual I've been reading about here, hard to start, and fouling plugs black.  The CSV seems to work as expected, but the WRD seems to be the issue (ignoring for now any IP screw adjustments).  The WRD does warm up enough to shut off the extra air with the slider valve, but the car really fouls the plugs quickly.  It has little real power, but will rev freely.  There were two thin shims between the WRD and the pump body, which I removed with no effect.

So I searched the web and found the picture of the WRD from JoeA, which I'll repost.  The second photo shows mine with an extra part.  (I've left out the slider and pin.)  That brass washer thing looks homemade.  It was found between the heat feeler and the lower stage of the WRD.  I think this could be the problem, as if it were left out, my heat feeler would push the slider further into the pin, which goes further into the pump, which leans the thing more.

My questions are:

1.  Is there some sort of gasket or O ring missing?  If I leave this washer out, the feeler would have a loose fit against the upper stage with the water in it.

2.  If water gets loose above the slide valve, would it go into the pump?  Or be sucked into the intake?

Any ideas?

Ron

[w113dude]

Ron,

I just did mine, you need to use rubber silicon around inner part of the thermostat pieces this along with the brass washer that makes the thermostat sit straight and a tight fit. One other thing if you are going to use a new thermostat (the new ones have a brass bottom piece & it's slightly a bigger diameter) make sure to make the hole on the brass washer so the new one will fit just like the old models, otherwise it will sit too high up and not push the pin far enough.

[DavidBrough]

I just wrap the joint with plumbers PTFE tape and have never had a leak.

[ja17]

Hello Ron,

Having the special washer is correct!  I cannot tell if my photo actually has it on the WRD or if I accidentally left it out of the photo.  However they are not made of brass. So yours may be home made and could be too thick?  Yes allow ing the pin to go further into the pump will lean the mixture. Make sure your special washer is not just cadnium plated. Nick it with a file or check it with a magnet. It it really turns out to be brass, you may be correct that it is the cause of your problem.  Keep us up to date!\

[Ron]

Hi Joe, I do not see the washer in your photo, but you are correct, it is cad plated and not brass.  So I put it back as I found it. 

BTW, the little slide piston has two different sides.  The side facing the heat feeler has a cylindrical depression with a "ring" spring along its wall, holding in two washers.  These washers have small holes for the heat feeler plunger.  On the pump side of this piston, there's a depression where the plunger to the pump sits.  It occurs to me this piston can be installed either way, so I put it back the way I found it - the two washer side going to the heat feeler plunger.  Is that correct?  If I put more washers here, the feeler would lean the pump and shut off air sooner, correct?

Today, after installing the WRD back, I decided to play with the ignition a bit.  In a lot of these threads, I've been reading that should be tried first.  I did get the engine to run better by advancing the distributor by ear - while running.  I also adjusted the idle down at the pump, 12 clicks, and the idle is working for the first time.

The big item of concern is now there's steam coming out the exhaust, and drops of water.  I did retighten the head bolts a few days ago, but did NOT release the water pressure from the cooling system before I did it.  I took the bolts to 70 ft.lbs. so maybe I may have to go to 80?

Regardless, I have to head out to TN for a few days and won't work on the car until next W.   

I'll bring my iTouch to keep track of this site, I'm addicted to getting this car on the road.  Ron

[ja17]

Hello Ron,

Yes the washers face upward.  Also Adjusting the idle thumbscrew on back of the pump adjusts just the lower range 1700 rpms or less. However this adjustment may help your idle plug fouling problem. If you are failure with the "split linkage CO test" do it at idle and at 3,000 rpms to find out where you are as far as fuel mixture at higher rpms.

You may have introduced some coolant into the combustion chamber and exhaust system by re-torqing the head while the cooling system was under pressure.  You will need to run the engine quite a bit to dry out the exhaust. Hopefully the problem will clear up.

Only re-torque the head at a higher amount as last resort. The 230SL engine has a lower torque spec than the 250 and 280 but they can take a higher torque if you must.

Engine timing at 3,000 rpms should be around 30 degrees BTDC.   I would do a check on it at this rpm.  

An IP rack adjustment can be used to lean the mixture at all ranges.  Make SURE everthing else is up to specs before you get into the internals of the IP.  Adding small washer shims  under the heat feeler will lean all the speed ranges of the IP even after warm up but it will also make the aux air supply for the WRD shut off earlier (richer mixture before warm up)!?

Keep us up to date. Let us know if you need clarification of any of the above.

[wwheeler]

Adding small washer shims  under the heat feeler will lean all the speed ranges of the IP but it will also make the aux air supply for the WRD stay on longer or possibly not go off at all.

Joe,

When you add round shims under the heat feeler, doesn't it DECREASE the time it stays on? Just want confirm and make sure I have it right.

[ja17]

Hello Ron,
Yes your right, sorry for the "brain fade".  Adding shims  will decrase the time that the aux air stays open as well as leaning the pump mixture.  One seems to counter the other.   

I will go back and correct the previous post.

So how productive can changing these shims be? Not much it seems.  I normally will change only the oval shims and/or the rack adjustment.   The WRD seems to be basically set to specs at the factory and as long as the "heat feeler" is working correctly the unit should be OK as is. ?

Other influences on the WRD would be engine coolant temperature and a good flow of coolant to the WRD.  One of our group reported that the coolant passage servin his WRD was plugged. Clearing it solved his problem. However the function of the WRD is easily checked by monitoring the air supply being shut of at the small filter when the engine is at oper. temp.

A split linkage test at 3,00o rpms with a fully warmed engine can tell me a lot about your problem.

[Ron]

Hi Joe, and all, I think I have a basic understanding of the WRD now, and it seems to be working.  It may need adjustment, but at least the car starts and drives well.  I leaned the idle adjust 16 clicks so far, and it still will backfire out the exhaust on decel (rich).  The plugs don't foul out, and the starter runs fast.  My ignition timing had been too advanced.

The big issue with me now is the steam in the exhaust (since re-torquing the head with water pressure - I did not know to release at the radiator cap).  It's been run about 10 miles now, for about 20 minutes, and still some steam.  Did I screw up the head gasket?  Crack the head?  (I went to 75 ft-lbs.)

Joe you said it would take time to get rid of the water?  Could you or someone give a guess before I go taking the head off.  I hate the thought. 

Thanks in advance,  Ron

[ja17]

Hello Ron,

Keep an eye on the water level, oil level and temp gauge.  Take a look at the plugs to see if any are coolant wet.  Also watch to see how fast the cooling system pressurizes after cold start.  If it pressurizes too soon, this may indicate you have a coolant system to combustion chamber leak. Squeeze the top radiator hose  as the engine is warming to monitor how fast the coolant system is pressurizing.Normally the coolang system will not pressurize until the engine reache s full temperature.

[Ron]

Hi Joe, thanks for the advice, I will watch all the fluid levels.  It finally has had a break in run, about 35 miles, up to 50mph.  You were correct, I did let in a lot of water, but it seems ok now.  There is some blue smoke now on hot start, but I think that is oil and maybe with new rings (which the PO put in) need to break in.  I read one of you old posts where new rings don't work as well as the old M-B ones (these new ones are Hastings), so I may have oil burning a bit.  The WRD works well and I lean the idle screw on the IP 24 click.

Ron