Well what is the issue then? Are you saying having an external thermostat is not a bad design issue? "Negative" is not much of a discussion or helps lead to an answer.

There are plenty of aluminum block engines that dont overheat. The crappy design is similar to the Jeep Cherokee from the late 80s that tried to use a variation of this type of cooling system. It had the thermostat in the block but it ran the external coolant tank. They were notorious for overheating as well. I still hold to it that having a stat outside the block only quadruples the issue in addition to the external coolant tank system.

 

No if my block stays at 180-190* (which it does) it doesn't matter where they put the thermostat.

The liner issue is well known and documented as to why,
The general idea on the headgaskets is that its the original head gaskets that are bad. Replacing once is usually the last time. Some people also blame the factory dexcool.

There are trucks made today where 210-220 is the normal operating temperature. Yes there aluminum no they don't have head gasket issues.

 

RMT - what about a 1/8 hole; or one of those "snap action" stats? Like http://www.summitracing.com/parts/emp-301/overview/

 

Its totally doable. All you would need to do is bore the manifold hole to 2" with a hole saw (easy). Then cut off the L pipe that runs to the upper radiator hose and replace with 1 1/2" I.D. tubing, that way you could fit a properly sized chevy thermo in there. Wow. I just thought of something. I'm thinking ill cut the pipe off, and weld a 1 1/4" expanded to 1 1/2" exhaust pipe 90* And see If I can get a full size chevy thermo in there.

 

Would a machined adapter plate bolted to the front of the manifold work to fit the Chevy thermostat? It would be nice if you could make this a straightforward conversion. I don't feel the need to do it but plenty of other people seem to be interested in this. Also, if you do bore out the manifold for the thermostat you could use an aftermarket Chevy housing to couple up an adapter hose: https://www.pegasusautoracing.com/pr...pID%3DCOOL32MM These aren't cheap but niether is your time.

 

Seems like an awful lot of work just for a thermostat. Granted, the Discovery has its temperature problems which have frustrated us all. But this is just a bit overkill, in my opinion. Wouldn't it have been easier, and cheaper, to install a new radiator and 180 deg thermostat and call it a day? Do what you want, it's your truck, but this method seems a bit questionable.

 

A remote inlne stat is an established alternative, as well as the 180 soft spring stat. Much of the work on these has come from working pro's like RMT, and we all benefit. A third option may be better yet. External adapter may have some spacing issues, the space in front of the block is so tight that many mechanics have to step outside to change their mind....

 

RMT, any news on where this went....