fatt_owl2.9
Active Member
- Joined
- Oct 8, 2008
- Messages
- 44
- Vehicle Year
- 87
- Transmission
- Manual
What's up guys, in my previous couple of threads I've made reference to the fact that I think my truck is running too cool, and I think it's part of why my fuel economy isn't as good as I think it should be.
The previous owner installed some kind of an adjustable thermostat and an electric fan, along with aftermarket temperature and oil pressure gauges. Most of the time, especially now that we're getting into cooler weather, the gauge reads about 120-140 degrees, even on freeway trips. On a really warm day, sometimes it might finally get up to 160. This truck has spent its entire life in the southern California deserts, where it remains, and the previous owner's son mentioned something about the engine being replaced, so maybe he went through the famous 2.9 cracked head experience, and installed the cool thermostat to prevent it from happening to the new engine, and also to maybe eke a little more power out of it.
I love my truck, it drives great, runs like a top and hasn't given me any trouble in the 5,000 miles I've owned it. The only thing I can really ask for is for it to get a little bit better gas mileage. From what I've also been informed, the lower running temperature isn't good for the engine internals, and doesn't allow moisture to evaporate from the crankcase like it should.
So what i'm wondering is, how do I fix this? Do I need to replace the actual engine thermostat with a regular 195 deg. piece? I consider myself to have a reasonable amount of proficiency when it comes to working on my cars, but this one has got me feeling like a retard. A couple of pics:
This is a shot of the top radiator hose, as you can see it's got some kind of a fitting hacked into it. I'm not sure if this is just the sending unit for the aftermarket temp gauge, or if it serves some other purpose. You can also see a little module right on top of the fan shroud (obscured by one of the A/C hoses) with some kinda thick wires plugged into it, I assume this is the controller for the electric fan.
Here's what gets me. A diagram for the supposed "thermostat adjustment", written with a Sharpie on top of the radiator cowl. How the hell do I adjust this? LOL. Anyone with half a brain or is familiar with this kinda setup, I'd love to hear your words of advice. Thanks in advance.
-the fat owl
The previous owner installed some kind of an adjustable thermostat and an electric fan, along with aftermarket temperature and oil pressure gauges. Most of the time, especially now that we're getting into cooler weather, the gauge reads about 120-140 degrees, even on freeway trips. On a really warm day, sometimes it might finally get up to 160. This truck has spent its entire life in the southern California deserts, where it remains, and the previous owner's son mentioned something about the engine being replaced, so maybe he went through the famous 2.9 cracked head experience, and installed the cool thermostat to prevent it from happening to the new engine, and also to maybe eke a little more power out of it.
I love my truck, it drives great, runs like a top and hasn't given me any trouble in the 5,000 miles I've owned it. The only thing I can really ask for is for it to get a little bit better gas mileage. From what I've also been informed, the lower running temperature isn't good for the engine internals, and doesn't allow moisture to evaporate from the crankcase like it should.
So what i'm wondering is, how do I fix this? Do I need to replace the actual engine thermostat with a regular 195 deg. piece? I consider myself to have a reasonable amount of proficiency when it comes to working on my cars, but this one has got me feeling like a retard. A couple of pics:

This is a shot of the top radiator hose, as you can see it's got some kind of a fitting hacked into it. I'm not sure if this is just the sending unit for the aftermarket temp gauge, or if it serves some other purpose. You can also see a little module right on top of the fan shroud (obscured by one of the A/C hoses) with some kinda thick wires plugged into it, I assume this is the controller for the electric fan.

Here's what gets me. A diagram for the supposed "thermostat adjustment", written with a Sharpie on top of the radiator cowl. How the hell do I adjust this? LOL. Anyone with half a brain or is familiar with this kinda setup, I'd love to hear your words of advice. Thanks in advance.
-the fat owl