heater - check -valve o-ring replacement

[rmmchl]

Im going to do this tomorrow. There used to be a "pictorial-how-to" on the body, interior page-does anyone know what happened to it. or where I can find it?

[66andBlue]

It is still here: http://www.sl113.com/forums/index.php?topic=6070
Good luck - it is a "fun" job!

[scoot]

We recently did ours.   The difficulties:  1) new o-ring is rather snug so moving the control for the valve is a bit stiff.    2) don't bend the cable for the control when you disconnect it or it will make the operation of the valve more stiff   3) make sure you don't drop the stuff inside the valve or you are screwed.  (we didn't).  Other than that it was easy and fun.    Any suggestions from anyone regarding how to make the o-ring less stiff?

[rmmchl]

does anyone know how to remove the limiter? I don't know how to get it off-I understand everything else

[66andBlue]

Scott,
from whom did you buy the O-ring?
I had tried several that I thought had the correct inside and outside diameter - sources: SLS, ACE Hardware, Home Depot - but only the one from MB had the perfect fit and plasticity.

[66andBlue]

quote:Originally posted by rmmchl

does anyone know how to remove the limiter? I don't know how to get it off-I understand everything else

First put a stiff wire from the engine bay through pipe into the valve body to make sure that it cannot fall or slip down.
2.  Loosen the screw a few turns and while holding the screw firmly with a channel lock push the valve body down gently about 1-2 mm.  If it stays there and doesn't slip further then you can take the screw out completely.
3. Push the limiter through a slit in the housing and take it out.
4. Insert the valve puller shown in Bob's picture and take it out.

[rmmchl]

buds sell the rubber o-ring-----------I still don't understand how to remove the limiter-How does it slide out?-It looks like it is locked in the ring housing-The limiter has a flange that sticks out if the ring to lock it

[66andBlue]

Take a look at the picture. The heater lever inside the cabin moves the valve stem via a linkage rod attached to a lever.  When you take the screw out you can remove the lever and see the limiter.
Assuming that your valve is not rotating freely you can do this without the risk of having the valve slip into the heat exchanger. However, it is always safe to push a rod into the valve through the pipe to prevent this from happening.
What keeps the limiter in place and allows it to function is that it is attached to the valve via the square opening. When you push the valve down then the limiter disc can move sideways.  In the wall housing is a slit through which the limiter can be removed.
Hope this makes it more clear, if not, keep on asking, it doesn't hurt.  
Make sure that Bud's sells you the Mercedes ring and not an aftermarket O-ring!

[bpossel]

Here is another alternative to Alfreds...
Note that Alfreds is the safest, but you need to remove the heater hose on the firewall and stick a wire in to ensure the valve doesnt drop into the abyss...  

What I did was to use a small bolt and screw it into the valve.  Tie a string to it and slowly push the valve down into the core a few mm, just enough to remove the limiter piece.  Then you can pull up and remove the valve...

Hope this helps.  See pics below...  Note: this procedure was posted by other members earlier, I just used it and it worked good for me.





ps.  Speaking of "hand made" parts...  the limiter looks very much hand made...  very uneven cut!  Must have been made after lunch and after a beer or 2...  

[rmmchl]

everything that could go wrong did-----the valve wouldn't lift out.Since I was changing it just to put a new one in, I just have left well enough alone since the old one worked---Even though I had rags around the valve, somehow, (murphy's law)the limiter dropped down into the space around the heater core and is nowhere to be found. Then I tried to tap the valve back in, and even though I had a coat hanger in the heater hose hole, it popped out and then the vlave dropped down into the heater coil. Now, I will remove heater box, ( which I need to try to fix the air box air flow director cable anyways-its been broke for years-I will have the glass people come and remove my windshield while its in the garage so I can get to that air directional cable---I hope when I get to the heater box I find the limiter that fell down in there somewhere. I have no idea how I can get the valve out of the copper heater box. Hopefully my radiator shop can take it apart and retrieve it. What a mess!!!

[mbzse]

quote:Originally posted by rmmchl

.../... the valve wouldn't lift out.../..

There is indeed a factory puller tool to perform this task of extracting the heater valve body.
However, one can of course use a suitable dia socket (same as valve housing w slit for limiter) and put washers on the M4 screw.
Then use a M4 nut to slowly and step by step pull the valve center
out. Wet with plenty of WD40 or the like and go slow, since there
is often a crust of verdigris holding the valve center firmly...[:0]

.

[scoot]

quote:Originally posted by 66andBlue

Scott,
from whom did you buy the O-ring?
I had tried several that I thought had the correct inside and outside diameter - sources: SLS, ACE Hardware, Home Depot - but only the one from MB had the perfect fit and plasticity.

I bought it from the MB Classic Center.  It fits correctly, it just seems that the operation of the lever is rather stiff.  Maybe it's supposed to be.

[rmmchl]

I retrieved the limiter piece with a magnet extension----------I found a magnet that is shaped like a donut, that is very small and powerful that I purchased from autozone tonight. It is a $4.99 extension magnet with a light-tomorrow I will remove the magnet from the tool and tie string on it and drop it down into the heater core hole. Hopefully I can pull it out. The valve already has a 4m screw-screwed into it, so hopefully I can pull it out with needle nose pliers.-I will update tomorrow.

[thelews]

If the heater valve on the 113 is the same as the 121 (190 SL), then the 3mm (thick) 13mm inside diameter, 19mm outside diameter O ring works perfectly.  $6.10 for 100 from www.mcmaster.com  part 9262K268

O-Rings, Cordstock, and Accessories
This product matches all of your selections.

 Part Number:  9262K268  $6.10 per Pack of 100
Type
 O-Ring
 
O-Ring Type
 Standard
 
Cross Section Shape
 Round
 
Width
 3 mm
 
Inside Diameter
 13 mm
 
Outside Diameter
 19 mm
 
Material
 Buna-N
 
Buna-N Type
 Standard
 
Durometer
 Hard
 
Durometer Shore
 Shore A: 70
 
Temperature Range
 -35° to +250°F
 
Color
 Black
 
Specifications Met
 American Society for Testing and Materials (ASTM), Society of Automotive Engineers (SAE)
 
ASTM Specification
 ASTM D2000
 
SAE Specification
 SAE J200


 
 

[scoot]

quote:Originally posted by thelews

If the heater valve on the 113 is the same as the 121 (190 SL), then the 3mm (thick) 13mm inside diameter, 19mm outside diameter O ring works perfectly.  $6.10 for 100 from www.mcmaster.com  part 9262K268

That doesn't sound right at all to me.  It's a cheap part from MB, the labor is way more than saving a few dollars by not getting it from MB.  At least for me, this is one of the instances that MB actually DOES have the correct part.

[thelews]

quote:Originally posted by scoot

That doesn't sound right at all to me.  It's a cheap part from MB, the labor is way more than saving a few dollars by not getting it from MB.  At least for me, this is one of the instances that MB actually DOES have the correct part.

Well, the MB part was installed on my 190 SL when I got it from the restorer, and it LEAKED.  These didn't and work very smoothly.  But, yes at $5.00 each, it's not an arm and leg from MB, so choose what's best for you.  Nice to have spares and to share with others.  I've probably given 40 away with satisfying results.