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DISCUSSION => Engine + Driveline => Topic started by: colin86325 on March 12, 2013, 09:28:45 AM

Title: thermostat seal question
Post by: colin86325 on March 12, 2013, 09:28:45 AM

What is the correct position for the rubber seal/o-ring for the thermostat?  The diagram shows #7 as going on the outside (vs being on the head side) of the thermostat.  In this configuration the metal thermostat is just sitting against the head with no inner seal.  Is this correct?

(http://static.bmwfans.info/images/epc/MjU2X3A=.png)

Title: Re: thermostat seal question
Post by: M3Philipp on March 14, 2013, 02:12:32 PM

Before like it shows in the graphic. Because the thermostat gets pressed against the ring inside the cylinderhead, that is pressed in.
Take a look when you have the thermostat removed, and you will see.

Title: Re: thermostat seal question
Post by: colin86325 on March 15, 2013, 12:31:57 PM

Ok thanks.  It just didn't seem right that there'd be a metal-to-metal contact.

Title: Re: thermostat seal question
Post by: valantis544 on March 15, 2013, 01:06:24 PM

Exactly as it shows in the image.

Title: Re: thermostat seal question
Post by: M3Philipp on March 15, 2013, 02:40:02 PM

Seen on another ones M42 engine, that the ring inside the head even became lose. I think they did put it in so that you can replace it later, in case the thermostat bottles up into because of the pressure, so that the head isnt destroyed but just that ring, which is replaceable.