Thermostat Mod 3.0

mattyk

Member
Feb 4, 2015
10
0
Pa
After having the LR-180 stat and the inline mod, I was not happy with either, I decided to come up with something that I was happy with and wanted to share it. So here it is. A hot side bypass thermostat.

Parts needed:
- Thermostat Housing from a 00-08 Jaguar S Type with 3.0 V6 or 95-00 Ford Contour with 2.5 V6 or 00-05 Lincoln LS with 3.0 V6. I got mine here http://www.ebay.com/itm/401059653945

-Stant 45398 for 180*(slight mod needed) or Stant 48499 for 190*(no mod needed)

-Gates hose 22639 for lower hose

-Dayco hose 71994 for bypass hose

-1.25 in barbed tee, or could use your plastic piece in factory top hose. I bought a stainless steel tee at local hardware store

-32mm rad hose gauge adapter to use as a bleeder.

The Stant 45398 stat I modded slightly by drilling and riveting a 5/16 fender washer to the bottom of the bypass plate to lower the temp the bypass is closed. Without this it still works but bypass wont completely close til about 192*. With bypass closes around 185*. I used a 5/16 fender washer because its what i had laying around the shop. I had to drill out the 5/16 to 7/16 to clear the stem. Center it and drill and rivet to stat bypass plate. Be sure you can move plate past the stem of stat so the stat can open without interference. I also drilled a 1/16" hole on top of stat for air bleeding top hose

The housing comes with a thermostat. Do not use it. The original setup for this housing was for a cold side setup like the D2 engines.

Bottom hose I used small piece of factory hose to the tee and kept it as close to rad as i could. Install tee then cut to fit the gates 22639 between water pump and the tee. Use 2 hose clamps on tee where 22639 connects to it. Slightly bigger hose.

Top hose I used the stock hose from intake outlet to stock bleeder tee just cut it a bit shorter. Install new bleeder to that. Then i used a piece of factory hose to make the 45 bend to inlet of stat housing. Cut to fit factory hose to rad to stat outlet. Then cut to fit Dayco 71994 from housing bypass outlet to the tee on lower rad hose.

I've been running this for 4 months now. No issues. Temps are around 180*-182* in the the cold. Idles at 182*. Ambient temp of 70* highway 182*, city traffic 182*-185* idle 183*.

Warms up as fast as factory setup and stable as the inline stat mod. Best of both worlds. Only reason i didnt like the inline mod was the pressure when stat was closed and I had to cover 2/3 of my rad in winter to get it up to temp.

This has not been tested in summer heat with ac on yet, but temps should be the same as the inline mod temps in summer which for me was around 190* as bypass will be closed and will be acting just like the inline mod.
 

ozscott

Well-known member
Mate looks good. Why didn't you like inline top hose stat? There is a bypass in the sense that the coolant will pump around the heater matrix and I put a small 3mm hole in addition to the stock bleed hole of about the same size. In 41 degree C days it hasn't broken 90 degrees C and most of the time runs at 82 around the city and 84 on the highway at 100kph. Cheers
 

mattyk

Member
Feb 4, 2015
10
0
Pa
The inline thermostat works great in warm Temps. I was happy with that. What I wasn't happy with was it's performance in the winter. With Temps in the teens it would only get to 150*. I had to cover my radiator to get up to normal operating temperature. Most likely because of the 1/8" hole drilled into state.

Another thing I didn't like was when the state was closed was the pressure in the post water pump and in heater matrix. There seemed to also be vacuum on the inlet side of water pump. Worried about pump cavitation.

The heater matrix is a bypass in the inline setup but a 5/8 hose can only flow so much. At higher rpms the pressure and cavitation begin with closed stat. As with my bypass stat the bypass can take full flow of water pump with closed stat.

With all that said this is mainly for people who live where winters are cold. If I lived in Texas or Florida I would be happy with the inline thermostat mod.
 

mattyk

Member
Feb 4, 2015
10
0
Pa
Damn, does sound like a good time. Haha. Disco currentlyrics not running. Loud clanking sound from cam area and multiple misfires all started at same time. Oh boy.