Author Topic: WRD Thermostat  (Read 1944 times)

Benz280

  • Full Member
  • Senior
  • ***
  • USA, NJ, Jersey City
  • Posts: 216
WRD Thermostat
« on: June 13, 2022, 14:09:48 »
Picked up this new WRD thermostat 30 Degree Celsius. What concerns me is that it does not fit within the washer ring.
According to a local shop, they say its ok to sit on top of washer .  I feel this would make a big difference in plunger length .
   
1971 280SL 4 Speed
1995 E320 Cab
1965 Shelby GT350

roymil

  • Full Member
  • Senior
  • ***
  • USA, TX, Austin
  • Posts: 177
Re: WRD Thermostat
« Reply #1 on: June 13, 2022, 14:25:20 »
I ran into this same problem and remembered Tom Horvath of Yankee Diesel mentioned it at PagodaFest SanDiego when he gave a presentation about the Bosch FIP's.   I emailed him about it later and here was his reply (which worked perfectly).  I chose to fix the washer.  -Mark

>>>>
Thanks for reaching out. We are always happy to hear from enthusiasts like yourself.

In response to your thermostat question, here are the facts:

The old style rubber insert guiding the pin has an O.D. of 10.3mm and the sealing washer that the thermostat rests on has a hole with an O.D. of 12.3mm.
No problem here.

The later style brass insert guiding the pin has an O.D. of 1/2"
That protruding 1/2" guide has a difficult time going through a 12.3mm hole.

Your choices are:
Drill out the hole in the washer to bigger than 1/2"
OR
Machine the protruding brass down to smaller than 12.3 mm O.D.

In a case you do not feel like drilling or machining, we would be happy to offer you either version for purchase.

With hopes that this helps.  -(Tom Horvath, Yankee Diesel)
Mark Miller
1968 280SL
Rode in his pagoda's first mile.

Benz280

  • Full Member
  • Senior
  • ***
  • USA, NJ, Jersey City
  • Posts: 216
Re: WRD Thermostat
« Reply #2 on: June 13, 2022, 15:29:50 »
Thank you very much, so in other words , the replacement is not really a replacement but you can make it work.   
1971 280SL 4 Speed
1995 E320 Cab
1965 Shelby GT350

Benz280

  • Full Member
  • Senior
  • ***
  • USA, NJ, Jersey City
  • Posts: 216
Re: WRD Thermostat
« Reply #3 on: June 29, 2022, 12:48:27 »
In my continued search to identify a cold start idle issue, new WRD thermostat replaced.
Starts are very low RPM, stalling occasionally. Burps, spits a bit until warm.
Once warm idles around 1000, reducing idle with air screw affects initial cold start and won't idle unless accelerator is maintained.
I'm thinking , initial start up should be around 1200 RPM then drop to around 850 once warm .     






1971 280SL 4 Speed
1995 E320 Cab
1965 Shelby GT350

Jordan

  • Full Member
  • Platinum
  • ******
  • Canada, ON, Jordan
  • Posts: 1409
Re: WRD Thermostat
« Reply #4 on: June 29, 2022, 16:22:13 »
Have you confirmed your WRD is functioning as it should?  Unscrew the air filter and confirm it is sucking air when cold and shuts off as the engine warms up.  Mine still has a very tiny bit of suction when the engine in warm.
Marcus
66 230SL  Euro 4 speed

Benz280

  • Full Member
  • Senior
  • ***
  • USA, NJ, Jersey City
  • Posts: 216
Re: WRD Thermostat
« Reply #5 on: June 29, 2022, 21:03:15 »
Checked when warm, no air being pulled in ( Will check cold in the AM )
Another thought, I notice that when I pull a spark plug wire of the cap, the spark color is orange yellow with engine running. I would expect it to be a blue ?
Coil replaced last year, anything else ? 
Thanks
1971 280SL 4 Speed
1995 E320 Cab
1965 Shelby GT350

gcw206

  • Full Member
  • Regular
  • **
  • USA, WA, Seattle
  • Posts: 76
Re: WRD Thermostat
« Reply #6 on: July 01, 2022, 12:21:35 »
Hello,
Try Authentic Classics, they have a correct collar that will work.
GCW

Benz280

  • Full Member
  • Senior
  • ***
  • USA, NJ, Jersey City
  • Posts: 216
Re: WRD Thermostat
« Reply #7 on: July 01, 2022, 14:51:39 »
So, when engine is cold, air being sucked in ( Air Filter ), when engine is hot - No Air Being Sucked ( Does this mean all is working correctly ? )
1971 280SL 4 Speed
1995 E320 Cab
1965 Shelby GT350