Tested , replaced electrical motor , all silicone high quality seals/gaskets , rebuild or changed the mechanical movement  , GREAT condition , very hard to find.. It was tested and is 100% perfect . If the buyers decide to return the unit , all the electrical functions must be in working condition , the on / off heating valve must be fully functional , and my seals must not be altered . I test all my parts before selling them , and I will work with the buyers to solve any problems . All 14 screws I used are stainless steel , marine grade , never rust. High quality Silicone or Neoprene new seals. Please use recommended antifreeze .

FOR $325 , I HAVE THE SERVO WITH NEW , NEVER USED ,ALUMINUM BODY ! ( see my eBay items for sale )

YOU MUST RETURN YOUR OLD UNIT 7 DAYS FROM RECEIVING THE NEW ONE , OR YOU WILL ACCEPT $ 150  LIABILITY .The core unit must  not being open ! 

Before I mail the unit , I will provide the buyer with detailed pictures of inside the unit , separated parts and motor.

FITS 

w107 W123 W117 & W116 450SL ,380SL  300SD , 300D ,  300TD , 450SEL 280SE 280CE 280SL  450SLC 380SLC

Attention to all buyers : 99.99 % of those units fail because the middle plastic part crack , damaging the motor and the mechanical movement  inside . I highly recommend the use a inox metal bracket , just like the one on my 

pictures . It will save you a lot of money , and it will prolong the life of those capricious units. I may sell all my units with the bracket install. It's not very pretty , but very effective . Please call before the purchase because a lot of times you may have an additional problem with the amplifier , vacuum lines , or the push button unit. I will be glad to provide you with technical details , troubleshooting suggestions and electrical diagrams , if needed it. Cris 8054559477 .

I have few units so new pictures may be added.

For $50 extra , I can deliver a Heating Servo Unit with NEW aluminum body ( see my other add )