Milodon 16406 or Speedway Motors 910-15703 High flow T-Stat fit very "loose" inside housing? 1971 Dodge/383

[62maxx]

Greetings,
I just did a "dry" install of the new high flow T-stat and it seems to fit very loose inside the housing with the gasket installed and the water neck bolted in. I can take a small pick and when I pull it up, it will lift up over a 1/4" creating a huge gap for coolant to flow around the T-stat. So with that in mind, I'm thinking once the water pump starts rotating, the T-stat is going to "bounce around" inside the housing and it's not going to "work" at all. I have a 440 Source housing and a stock water neck. With the stock T-stat being larger in circumference, it fits perfectly into the water neck (as it should) with the high flow, it's way smaller and it seems it's too loose to "seal" itself. Soooooo, any help would be really appreciated! Thanks in advance!

 

[toolmanmike]

Looks you got the wrong thermostat

 

[DodgeBoy5150]

Sorry to say --that high flow stat looks like it's for a /6 or '79-up small block.
The larger size high flow stats for the older style housings are out there-- ebay for NOS or Mr. Gasket and Flowkooler sell new.
Flowkooler sells a modded 160 F smaller stat that will fit the larger style housing.

 

[Beekeeper]

Looks like a slant 6 stat to me as well,

 

[62maxx]

Thanks guys.....you are correct. it's the wrong one. I appreciate your help!