Author Topic: WRD oval shims  (Read 2088 times)

Lorsar

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WRD oval shims
« on: September 07, 2021, 19:56:27 »
1968 280 SL US - So I have been going through the linkage tour and starting aid - I have adjusted the venturi, adjusted the linkage, cleaned the contacts on the csv relay, replaced the FIP air filter, adjusted the css and readjusted the idle air and fuel many times.  Now where I am at is that the car stalls after warming up a bit when the temp is around 170. From the forums, I believe I need to add oval shims to the WRD - problem is there are currently no oval shims.  Does anyone have a template doc I could use to make some? 
Lori
1968 280SL (US)

Pawel66

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Re: WRD oval shims
« Reply #1 on: September 07, 2021, 19:59:25 »
I produced some once, they fitted.
Pawel

280SL 1970 automatic 180G Silver
W128 220SE
W121 190SL
G-class

Lorsar

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Re: WRD oval shims
« Reply #2 on: September 07, 2021, 20:25:34 »
Perfect!  Thanks Pawel
Lori
1968 280SL (US)

TJMart

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Re: WRD oval shims
« Reply #3 on: September 07, 2021, 20:39:46 »
Lorsar,

Kinda off topic but the Charlotte area Pagodas are getting together on 9/25 in Mooresville. PM me if you are interested.

Tony
Tony
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wwheeler

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Re: WRD oval shims
« Reply #4 on: September 07, 2021, 21:32:39 »
How does the engine run (mixture wise) when cold and then when totally warm 180*+? Does the engine temperature ever get about 170*? Does the air at the WRD shut off at 170*? The air should shut off at 170* and when the WRD becomes inactive. Changing oval shims ONLY effects the mixture when cold, not at full operating temperature.

Stalling or hesitation when accelerating could be a lean condition. Have you tried the split throttle test to confirm if rich or lean? 
Wallace
Texas
'68 280SE W111 coupe
'60 220SE W128 coupe
'70 Plymouth Roadrunner 440+6

Lorsar

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Re: WRD oval shims
« Reply #5 on: September 07, 2021, 21:55:26 »
I have done the split linkage test both cold and hot.  It was running really rich but I think I've got it adjusted to "less rich than what it was".  When I start it, I just let it sit and idle. At the moment it idles cold around 950.  After about 3-5 minutes as the temp goes up, the idle starts dropping and will stall.  Then when I restart  it, it's fine and idling around 800.  Putting in R or D drops the idle more than it should (around 650) but it no longer stalls there at least. 
Lori
1968 280SL (US)

Lorsar

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Re: WRD oval shims
« Reply #6 on: September 07, 2021, 22:02:46 »
I forgot to add, no stalling/hesitation on acceleration. 
Lori
1968 280SL (US)

wwheeler

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Re: WRD oval shims
« Reply #7 on: September 08, 2021, 04:13:50 »
The throttle solenoid (called constant speed solenoid) is responsible for keeping the idle the same when the trans is put into R or D. It should not change very much when it engages. Sounds like that needs to be adjusted.

What were the results of the split linkage test cold and hot? The idle will slowly lower as the engine warms up. That is a normal function of the WRD. You can also do the split linkage as the engine warms up to determine how the mixture changes. I suggest you do that to determine if you are rich or lean when it starts to stall. You need this info first before you will know how to address your problem.

Does the WRD air flow stop when the engine is at 170*?     
Wallace
Texas
'68 280SE W111 coupe
'60 220SE W128 coupe
'70 Plymouth Roadrunner 440+6

Lorsar

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Re: WRD oval shims
« Reply #8 on: September 09, 2021, 02:54:46 »
So I did a split linkage while it was warming up and it didn't happen.  I put the linkage back on and it started to stall.  Notice a slight push in the fip linkage that I hadn't notice previously.   Adjusted the linkage. After letting it cool down,  I tried again and it stalled.   

Checked the airflow with the fip air filter off and it seems to open and close during that warmup.  It closed off and I check again and feel suction.  I already purchased a new thermostat and was planning to replace.
Lori
1968 280SL (US)