mga thermostat

[73series88]

hey guys
when i had first put my rover together i bought the standard 2a/3 thermostat from RN but it wasnt even close to fitting
mine looks flatter. the truck would run very hot so i ditched it all together wich made summer driving very nice. but as the weather is getting cold the drives have been cold to. wouldnt you know it in my mga parts bin i had a couple of old mga thermostats. pulled off the thermostat housing and put one of those mg ones in there and it fit perfectly. and also brought up the engine up to a nice operating temp. i dont know maybe i have an early style thermostat housing but i couldnt find anything from any suppliers. just thought i would share my small adventure this morning.
cheers aaron

[artpeck]

Odd as I just replaced mine and the RN standard issue fit perfectly and now the engine runs at the proper temp. Maybe you can post a picture of the housing. Curious why it is different as we both have 73 88s it appears.

[Les Parker]

Sounds like you have a bellows type early IIa stat and housing.
You could update with a used later type and then you can use the correct stat for summer/winter application.

http://www.roversnorth.com/store/images/category/medium/44-series-thermostat.jpg

[yorker]

it used to be pretty common to fit an American "flat" thermostat to the 2.25. Maybe you have one of those fitted. The skirted one that is supposed to be in there

http://www.lrfaq.org/Series/Drivetrain.SkirtedThermostats.html

Series Land Rovers
Coolant Flow & Heat, or why you use the skirted thermostats in Land Rovers by Dave Lowe
The Series III and earlier thermostat housings have an oval opening in the side, which leads to the bypass hose. The purpose of this is to prevent the pump from "dead heading" or churning when the thermostat is closed. In other words when the thermostat is closed to the radiator there would be no flow and therefore no circulation through the engine, which would be most unhealthy. To prevent this happening, the oval opening allows water to by-pass the radiator and circulate water throughout the engine alone.
So, we have a pump that circulates water continually through the engine regardless of the thermostat position. When the engine is cold all the flow goes through the by-pass opening and through the engine because the skirt is raised. As the temperature rises the thermostat begins to open to the radiator but as it does so the skirt descends and proportionately closes off the by-pass opening until the flow is solely to the radiator. If you use the "flat" single acting thermostat the by-pass opening remains open continuously regardless of engine temperature. The pump of course will pump the same amount but the flow will take the line of least resistance which is through the by-pass rather than the long way around through the radiator, and under high ambient conditions will cause the engine to run hotter than it should. The temperature sender of course is at the front of the engine and does not give you the temperature at the no.4 end of the block. You will therefore have a condition where the temperature on the gauge is reading a bit on the high side but the temperature at the back is significantly higher. I consider this to be one of the causes of the manifold cracking and I`ve cracked a few before I found out about the operation of the double acting thermostat. I used to use the flat type because I could get them for 195.F.
On engines from the 110 onwards the thermostat housing was changed and a flat single acting thermostat is standard. Instead of the large oval opening it has a hole about 3/8" in diameter instead. This is calculated to provide sufficient flow when the thermostat is closed but has a higher resistance than the radiator circuit, consequently the line of least resistance when the thermostat is open is through the radiator not the by-pass.

[73series88]

my 88 didnt have a motor in it when i got it
and the chap i bought it from had told me i was a 2a motor
had a solex carb and generator mount. it doesnt have the series 3 crank case ventilation either. open breather in oil filler and valve cover.
didnt know anything about the improvement with the skirted thermostat. skirted thermostat wouldn't even come close to fitting
yikes!!!
i would say thats a must read.
so it must be an early 2a motor
i'll get some pics of it.
aaron

[gudjeon]

I fitted the common and dime-a-dozen chevy flat stat in 195f. I made a replacement skirt ring for it to sit on in the housing. I used a thin copper sheet formed into a ring to replace what the skirt used to do. I do not recall the width. Fits perfect and O-ring holds it all like it should. Running this for 5 years now through summer and winter. Ain't cracked anywhere yet.

[Enigma]

Wouldn't a blanking plate of 1/8 flat iron with a 3/8 hole drilled through it and a couple of gaskets accomplish the same thing?