37 Special valve body butterfly seized help .

[37buick]

    Hello  everybody !    Still  trying  to   work   on  my  37   special  over  here .   My valve body butterfly   shaft  is  seized,  and  actually   the  butterfly  broke  by  just  forcing  on .   It  seems  impossible  to  get   that   shaft  off  now .   Any  suggestions  ?   And  if  i  ever  get  that  off  ,   can  it  be  replaced  or   i   should   get   a   new   one  ?    

 

                                                                                                                                                                        Thanks     and  have  a   great day !

[buick special]

I always found that putting some Kroil on a frozen part for a few days usually frees it up

[dibarlaw]

It took me several days of penetrant then heat and some light tapping to finally break mine loose then had to spot weld the damper return spring plate back on. I have to do the same with my 1925 damper unit.

[37buick]

 I guess im going  to  start spraying    some  good stuff on  that but    im  already  preparing  myself  for  the   next  step  , replacing   the  damper itself .    Thanks !!!

[Buicknutty]

I gave up on mine off of the '41 Roadmaster, I soaked it with penetrant for many days, heated it hit the end of the shaft, etc. All to no avail. I ended up bending them out of the way.

It must of been many decades, perhaps since nearly new that these were working.

Keith

[37buick]

        So  if  thats  the  case   ,  i  can   just    remove   the  butterfly ?

[Bloo]

Are we talking about the heat riser? If so, heat riser solvent works amazingly well, and the best of that crop, the Chrysler version, is still available. They have renamed it "Rust Penetrant", MoPar part number 4318039AC (shake before using!). It would work even better if the car were together and you could heat cycle it a time or two. Since it isn't, let is soak for a couple of days, then tap. It helps to keep spraying a little on now and then as it soaks.

 

IMHO this stuff is even better than Kroil (and Kroil is great stuff).

 

I wouldn't remove the butterfly unless a whole bunch of 37 Buick drivers tell you it's ok. Most cars that have heat risers need their heat risers. There are exceptions, but few.

Edited September 30, 2017 by Bloo (see edit history)

[FLYER15015]

Mine was frozen so bad and partially open, so I chiseled it out, cut a piece of 14 gage to fit the hole and brazed it in, in the closed position and never looked back.

[Frank DuVal]

I take it '40 Buick heat risers work opposite of small block Chevys and '56  Buicks.  On those cars, the butterfly needs to be open, or excess heat will go through the intake manifold after the engine warm up, overheating the engine. Brazing the valve closed on these will harm the engine.

[Ben Bruce aka First Born]

Closed and open is relative.

 

  Ben

[Bloo]

I wish I could find a good graphic to illustrate this. The way most inline engine heat risers work is completely different than a typical v8.

 

Usually on a v8, there is an exhaust passage through the intake manifold. When the heat riser is "closed" (cold) it blocks the exhaust on one bank, and the exhaust from that one bank has to go through the passage to get out the other side, heating the intake as it goes. When the heat riser  gets hot, it rotates 90 degrees to full open.

 

On an inline engine, the heat riser usually never blocks anything. When it is in the cold position, exhaust is directed up near the carburetor and then it flows back down. When it is in the hot position, the exhaust hits the plate (butterfly?), which diverts it straight out the exhaust pipe. Cold to hot is probably less than 90 degrees rotation.

 

I still vote for fixing it.

Edited October 2, 2017 by Bloo (see edit history)

[Joseph P. Indusi]

In my experience with straight eights, it is better to leave it "open" allowing exhaust gases to go directly out exhaust pipe if you cannot free it up.  This will be fine in most instances unless the temperature goes lower than 50 F in which case there may some icing on throttle plate and a little longer warmup will be needed. 

Joe, BCA 33493

[37buick]

    So ...   i  decided to  just  find  a  new  heat riser .   Called Dave Tacheney   and told him   that  i  had  a  carter  in  that  car .  Explained  to  him  that  as  some  members here told  me  that  some  37s  had  the  stromberg  replaced  by  dealer back  then .     He  never  heard   such  thing ...