Thermostat replacement question

[bpenn1980]

Here is the background of my situation.

Bought the truck in November '07. Flushed coolant system very thoroughly in December but I didnt replace the thermostat for some reason. I did the RavenTai temp gauge mod in March this year and noticed my truck was running hot. Now that the temps have spiked here in SoCal I noticed it running real hot this weekend.

Before I order a new radiator, I want to replace the thermostat.

My question to all of you is this: How much coolant will drain in order to do the thermostat? If I refill with water instead of a 50/50 mix will my temp gauge readings be accurate? I'd rather not dump in $50 worth of MrT red just to find out the new thermostat didnt have an effect and have to drain it out again in a few weeks when I replace the radiator.

Thanks

 

[3sacrwd]

I didn't lose much when I did mine. Maybe a couple of quarts or something. I didn't drain anything, just used a turkey baster to suck the anti-freeze out until I touched the fins in the radiator. Lost a little emptying the upper hose. A little water won't hurt anything, but I would suggest that you keep it to 50/50.

 

[e9999]

the temperature "readings" won't be affected by what fluid you are running, it will read whatever temperature the fluid is (assuming the guage is OK). What fluid you are running could have a minor effect on coolant temperature because of slightly different thermal properties (conductivity, heat capacity, density, and also viscosity if it changes the flow rate) but I doubt it's very significant. And certainly not very much if you're talking about minor mix changes.
Of course, different mixes may have a big effect at freezing temperatures.

Anyway, just catch the coolant and put it back in through a filter. It's not as if this stuff goes bad instantly when exposed to air.

 

[CJF]

$50??

More like $2-$3 for what you can't catch/re-use.

Oh and I would *definitely* do the fan clutch as well. In fact, given one or the other, I'd go for the clutch.

Curtis

 

[bpenn1980]

$50??

More like $2-$3 for what you can't catch/re-use.

Oh and I would *definitely* do the fan clutch as well. In fact, given one or the other, I'd go for the clutch.

Curtis

$25 bones a gallon. Didnt know the block wouldnt drain when I pulled the thermo, so this sounds like it'll be easier than I thought.

Did the fan clutch mod on my original fan clutch. Temp's definitely drop when I rev engine now.

 

[96r50]

The thermostat location on a 1FZ is different than the 3FE. The 1FZ thermostat is pretty low down, I think you would lose quite a bit of coolant from the rad and the block.

 

[CJF]

The thermostat location on a 1FZ is different than the 3FE. The 1FZ thermostat is pretty low down, I think you would lose quite a bit of coolant from the rad and the block.

Yeah, but you can still catch most of it. Drain the radiator first, etc.

 

[bpenn1980]

Searched, but didnt find anything definitive. Do you guys suggest using RTV gasket stuff in addition to the thermostat gasket?

 

[breathed]

No RTV. Just install the gasket properly. It fits over the the edge of tstat body.

 

[bpenn1980]

Crazy when parts you previously replaced reach the end of service life. Even crazier that I plan to still own the truck in another 10-years! Replaced thermostat in April 2008 and it just failed open on a long drive home. Good news is I just ordered a replacement along with new water pump yesterday for installation next weekend! Good timing for me