As I view this image of the coolant flow for the V8i engine from the RAVE manual:



It's not crystal-clear exactly which side of the thermostat fits into the block. I've always heard SPRING-SIDE into the block, but after examining my WAHLER (German) thermostat, (and THE coolant flow direction EXITING the block at the housing that feeds the upper radiator hose) it sure seems like the SPRING-SIDE should be out for optimal operation of the thermo-valve. And the spring side DOES fit into the (top) radiator hose housing. Worse - the close up drawing in the same manual gives no better indication of this "polarity":



The Wahler thermostat in question: (Wahler #W0133-1636663 (88 C)


Any thermostat polarity insights specific to the V8i engine in this 1995 Discovery I ???? (SPRING: IN or OUT for the V8i?)

thanks!

Bob Peterson
Portola Valley, California
Algernon, 5-speed (now rare!) 1995 Discovery

 

spring in on mine....

 

Spring faces in cause the heat probe it that side, engine heat causes spring to compress opening the valve, there should be a weep hole in the lip of the stat, it goes at 12 o'clock to bleed air from the system

 

Thanks! In 122K miles, I've changed the thermostat TWICE and never questioned "spring-in." I'll stick with what works then.

Bob

 

I'd like to add that i have purchased thermostats before that came with no "weep" hole as Tom mentioned above.....it's a good idea to drill one if there isnt one...its easier to bleed the system

 

X2 on all above - and if your just purchased Rover has no stat, most likely that is because of overheating. Will run without a stat, my D1 would make about 145F. Needs a working stat. I prefer the 180F models.

 

Here's a good one with a jiggle pin https://landroverforums.com/forum/di...rmostat-51327/

 

Do not use the fail safe ones mine killed it