Frozen Climate Control in Exhaust Manifold

BigSky
BigSky Senior Contributor
I had to remove the exhaust manifold on my 37 coupe & discovered the door inside the manifold is frozen shut.  In other words exhaust always is forced into the intake manifold even with the engine fully warm. 

I’m using kroil to soak everything I think may be the cause but not knowing how this works or comes apart, I’m kinda shooting in the dark.   Any ideas, photos, & explanations would certainly help.  I really don’t want to break it as I try to free it!

Comments

  • I'm not an expert, but those dampers are used to heat up the intake manifold for better starting/running when the car is cold, especially in winter.  There should be a thermostatic spring which regulates it, assuming it can move freely.  Yours seems to be seized.

    If you only drive in fair weather, it's possible you don't need this damper at all.  Some guys will remove it and plug the holes in the manifold.  Some guys will even just place a bolt through the holes to cover it up.

    Personally, I would try to get it working as it should.  Soaking it in kroil sounds like a good start.
  • BigSky
    BigSky Senior Contributor
    I believe your right on the money, functionality & description is my understanding as well.  
    Agreed, prefer to get it functional!
  • BigSky
    BigSky Senior Contributor
    After soaking with lots of kroil, a block of wood & a gentle 3lb hammer did the job.  The entire unit is now removed & I’m not sure it’s going back in.  I read an older thread which many expressed issues of the unit freezing up again from lack of use & vapor lock issue potential.  Since it’s a fair weather vehicle I really don’t need it in use. 

    Now the two studs which attach the intake to this exhaust many need drilling out as they broke off during removal.  The joy of old cars....
  • use Kroil on every nut , overnight. Most of the time on a long stud, the new one will be slanted and cause more problems because the drilling was not 90 degrees to the block.
    Use a 90 degree square next to drill bit. Really a two person job for success.
  • Geoff
    Geoff Senior Contributor
    I recently did a similar thing n '36 H8.  I just left the  valve in the wide-open  position,  and put a wee blob of stainless arc weld to hold it there. 
  • BigSky
    BigSky Senior Contributor
    Fortunately, all the studs are drilled & retapped & while the climate flap is working, I do agree, it’s not worth risking it getting stuck closed again.   

    Other than using something like Geoff did to secure it open, which is perfect by the way, what have others done to keep this open?  I was even thinking of making a plate to cover it & save the unit.


  • On my 36 Terraplane ,which has a manual summer/ winter plate you turn. I took a hammer and punch and broke the damper off and left the original plate cover in place. As i don't see ever driving it in cold weather it is really not needed.
  • BigSky
    BigSky Senior Contributor
    Dan, 
    have you got a picture of how it looks?