Install report: SPD 170 deg thermostat

[Mokume]

Well at least it's not like doing it on an audi 6 cyl . As I do shorter trips now <10 miles, I want the engine to quickly reach operating temp to burn off any contaniments, esp fuel.

You can't be serious! All that needs to be removed to replace a thermostat???

Sponsored

 

[rydfree]

You can't be serious! All that needs to be removed to replace a thermostat???

No but he had to find that missing 10mm socket

 

[dtech]

You can't be serious! All that needs to be removed to replace a thermostat???

From what I heard from a friend who had an Audi A4 V6 (which he liked until it was out of warranty) , the pic makes it look worse than it was as far as removing the front end stuff, however the timing belt had to be removed to change the thermostat. An alternate method could be loosening the entire drive train and moving the engine into what Audi called "service position"

 

[Mokume]

No but he had to find that missing 10mm socket

When I used to wrench professionally and dropped a Craftsman tool somewhere in the engine compartment I'd spend maybe 5 minutes to locate it (being certain that it would not be a hazard), if it was a Snap-On I'd resume the work only until after I found it...

 

[Mokume]

From what I heard from a friend who had an Audi A4 V6 (which he liked until it was out of warranty) , the pic makes it look worse than it was as far as removing the front end stuff, however the timing belt had to be removed to change the thermostat. An alternate method could be loosening the entire drive train and moving the engine into what Audi called "service position"

Remove the timing belt? What are these engineers thinking?

I once did some major HVAC work on my Dad's '87 420 SEL, leave it to the Germans to over-engineer things. Some of the system's plenum door operations would start off as being electrical, change to vacuum, then back to electrical again for one simple operation...an operation the Japanese would be content to use a simple cable.

Please remind me never to buy an Audi, let alone work on it!

 

[MXGOLF]

Hi Folks,

Ford chose a thermostat operating range for a reason and there is a ton of testing behind this choice. Changing to a 170°F thermostat is not a change I would make nor recommend to any forum members... I view this as a move into the unknown with unknown consequences that may occur... Installers beware...

Would not make such a change without factory recommendation.

best,
Phil

Hi Phil, OK for the unleashed tune they gave me new plugs and a new thermostat. So you are saying not to change out the thermostat? I know you know a lot more then me so I just want to be totally clear on this. I am assuming all the guys with the unleashed tune have done this??
Thanks,

 

[Frenchy]

Hi Phil, OK for the unleashed tune they gave me new plugs and a new thermostat. So you are saying not to change out the thermostat? I know you know a lot more then me so I just want to be totally clear on this. I am assuming all the guys with the unleashed tune have done this??
Thanks,

I'm sure Phil can explain a little bit better but put simple every manufacturer puts a lot of time and money into a vehicle during the Engineering Process to find the best parts for operating range. The thermostat is a big one on that. For whatever reason the factory selected thermostat 190 degrees or whatever it is Ford found to be the most optimal for the Ranger. My 93 Nissan Pathfinder on the other hand Nissan spent a lot of money and time on research and decided on 170° thermostat was Optimum. Put simple every Vehicles going to be different and that is why I Phil only recommends the factory. I actually agree with him on that too.

 

[JohnnyO]

From what I heard from a friend who had an Audi A4 V6 (which he liked until it was out of warranty) , the pic makes it look worse than it was as far as removing the front end stuff, however the timing belt had to be removed to change the thermostat. An alternate method could be loosening the entire drive train and moving the engine into what Audi called "service position"

If there's a way to make something more complicated, the Germans will find it.

 

[JasonTremor]

Hi Phil, OK for the unleashed tune they gave me new plugs and a new thermostat. So you are saying not to change out the thermostat? I know you know a lot more then me so I just want to be totally clear on this. I am assuming all the guys with the unleashed tune have done this??
Thanks,

If unleashed adjusted the engine calibration for the lower temp thermostat, you should be good to go as they would have adjusted all the fuel adder scalers and other engine temp dependent settings to work with it. From an engineering perspective you could argue the efficiency of the change, but I'll avoid that debate.

 

[Frenchy]

If unleashed adjusted the engine calibration for the lower temp thermostat, you should be good to go as they would have adjusted all the fuel adder scalers and other engine temp dependent settings to work with it. From an engineering perspective you could argue the efficiency of the change, but I'll avoid that debate.

Regarding the efficiency impact from said change it will depend on the vehicle. Some will be negligible, others not so much. Just depends on the vehicle. And I will agree that if the tuning company made the necessary changes to run said thermostat then you.may be ok. If not then I would not suggest.

 

[P. A. Schilke]

Hi Phil, OK for the unleashed tune they gave me new plugs and a new thermostat. So you are saying not to change out the thermostat? I know you know a lot more then me so I just want to be totally clear on this. I am assuming all the guys with the unleashed tune have done this??
Thanks,

Hi Mark,

My recommendation is based on the fact that the Ranger 2.3L has been extensively tested with the OEM chosen thermostat. There has been little or no real rigorous testing with a 170° thermostat that equates to long term verification of a different operating temperature, and its engine durability ramifications, particularly in winter when the thermostat gets a real workout of opening and closing frequently compared to summer. My point is you are in uncharted territory, short term, probably no ramification but long term engine durability is unknown. Stick with what is proven is the safe way to go.

That said, what is Unleashed's rationale for a new thermostat temperature and what type of long term testing have they done to verify there are no degredations to running a "colder" engine? My guess, it has to do with increased spark advance without detonation maybe? Don't know.... I would be interested if there was any in vehicle long term testing to any "Tune".

Way back in 1974 as emissions requirements necessitated higher temp thermostats to meet emissions performance long term and to prevent/reduce sludge build up in the cylinder heads as it was explained to me as a Newbie Ford engineer...

Best,
Phil

 

[Doc]

Hi Phil, OK for the unleashed tune they gave me new plugs and a new thermostat. So you are saying not to change out the thermostat? I know you know a lot more then me so I just want to be totally clear on this. I am assuming all the guys with the unleashed tune have done this??
Thanks,

You don’t need to change the thermostat, I have the 93 octane tune since 2019 and an occasional drag race…

Regards
Doc

 

[Mokume]

I'm sure Phil can explain a little bit better but put simple every manufacturer puts a lot of time and money into a vehicle during the Engineering Process to find the best parts for operating range. The thermostat is a big one on that. For whatever reason the factory selected thermostat 190 degrees or whatever it is Ford found to be the most optimal for the Ranger. My 93 Nissan Pathfinder on the other hand Nissan spent a lot of money and time on research and decided on 170° thermostat was Optimum. Put simple every Vehicles going to be different and that is why I Phil only recommends the factory. I actually agree with him on that too.

I remember very old school mechanics tossing the t/stat completely in an effort to repair an overheating engine, not bothering at all to determine what was causing the problem.

Then there's the more intelligent mechanics who will tell you that tossing the unit is dead wrong and that the engine is designed to run at an optimum temperature based upon many factors.

I was taught that an engine which runs cooler than what it was designed for is very detrimental.
Increased sludge formation is just one of them...

 

[JohnnyO]

I remember very old school mechanics tossing the t/stat completely in an effort to repair an overheating engine, not bothering at all to determine what was causing the problem.

Then there's the more intelligent mechanics who will tell you that tossing the unit is dead wrong and that the engine is designed to run at an optimum temperature based upon many factors.

I was taught that an engine which runs cooler than what it was designed for is very detrimental.
Increased sludge formation is just one of them...

I'm old and remember people removing the stat altogether, I might have done it a time or two myself. Later I read that removing it can also cause overheating because the coolant flowed too fast and didn't stay in the radiator long enough to cool off.

Depending on ambient temperature, engine load, those sorts of things, that it doesn't matter much what temp your thermostat is too. Hypothetically, say the coolest your engine is going to run is 195 then it won't matter if you run a 170, 180, or 190 thermostat.

At constantly cooler temps your internal clearances are wider. One reason why marinized automobile engines don't last long in boats is they run in a high load, high throttle, low temp environment. They either run very low-temp stats or no stat because you don't want the water from the lake, river, or ocean to boil and leave a bunch of crud in the cooling passages. Kills the motors though and you can't knock the heads off the block with a sledgehammer.

 

[Mokume]

I disagree, a thermostats job is to maintain a set coolant temperature within the engine as best it can within it's design limitations. If the engineers found that the optimum engine operating internal coolant temperature is, say 200 degrees they will specify a t/stat to maintain that temperature.

A thermostat set to begin opening at 170 degrees and to be fully open @ 180 will never achieve the desired 200 degree internal coolant temperature.

Sponsored