77A8F63D-03DA-4A7C-A2CC-FE8A316BE37A_zpsitta4uzf.jpg
Don't know what year, NOS thermostat housing
$50 plus shipping

 

That housing was used as:


’66 Tri-Carb, ’65 400-425(CAC & non CAC)


Mike

 

Also came on pretty much up through 69 non-toro V8s as well I'm thinking. My 69 H/O has one of these. I believe it was sometime in 1970?? they changed to the gooseneck bypass tube style?? Could be wrong on the exact year.

 

So THAT's what they are supposed to look like!


Well, yes and no
There are no fewer than five versions of that item. Note the PN and large ID "1" - there are also #2, 3, 4, and 5, and maybe more.
Database says the '129 is for
66-68 BB exc.(Toro, A/C or HDCooling) [Bypass hole 0.542"]
66 F85, 442, D88, Delta, S/F, 98 exc. CAC or Spec. Cool.
[Bypass hole ~0.50" (full dia.); 42° off Vertical, 48° off Horiz.]

info from paper 1966 Parts & Illustrations Manual

We also have

392099
Thermostat HOUSING, #2, [AL-U], OFFSET NIPPLE
1966 w/ L69 tri-carb; 66-68 BB (exc.Toro) w/ A/C or HDCooling, and all SB's
Large Nipple is OFFSET to RH Side
66 F85, 442, D88, Delta, S/F, 98 w/ CAC, Spec. or HD Cool
[Bypass hole 0.41-.43" (reduced dia.)

382543
Thermostat HOUSING, #3, [AL-U],
66-68 Toro, exc. (A/C or HDCooling)
ANGLED DOWN slightly vs. say the #1 or #2 housing.
[Bypass hole 0.54" (~full dia.)

393286
Thermostat HOUSING, Water Neck, #4, [AL-U],
66-68 Toro, w/ A/C or HDCooling
#3,4,5 are ANGLED DOWN slightly vs. earlier #1 or #2 housing.
[Bypass hole 0.40-.43" (reduced dia.)

404632
Thermostat HOUSING, #5, [AL-U], DEPRESSION cast in Rear, RH side
1970 ALL V-8; 1971 ALL V-8 (w/ AL water neck)
[Bypass hole 0.60-.62" (full dia.)

 

So who's buying it???

 

Chris, I have an NOS housing in the GM box w/hose, clamp, thermostat, and bolt. Part # on box is 231256 and cast # on housing is 409038. Do you have this one in any of your reference materials?

 

Well, I do now

Gr. 1.153
Casting # 409038
Thermostat HOUSING, ID #[none], Iron with J-Pipe
Most Olds apps w/ V8; use started in mid-70's, repl. for previous AL units
CASTING # 709038 vs PART Number 409037 per CD PNM; PN 231256 per CO user
By 1975 PNM publish time, the CI version was to replace all.

info per pg 1206 of the CD PNM


There is is at least one more type, for 403 Firebird type cars, nipple angled upward more

casting # 547083
Thermostat HOUSING, ID #[none], Iron with J-Pipe
Pontiac T/A Trans Am w/ Olds V8 e.g. 403 6.6L
Nipple is ~20° off vertical [vs ~52° std 1966+ Olds part]

 

1972 parts book shows the 386129 for 69 applications, although it seems a/c and toro don't use it.

If you have the J-pipe on the housing, it's iron and if it uses the j-hose, it could be either.