So yesterday was day two of the cooling system overhaul. Day one consisted of replacing the fan clutch.
My reasoning for doing it in two days are as follows:
1) I'm lazy.
2) I didn't want to wait for the coolant to cool down again.
3) While I wanted to replace everything for peace of mind, I also really wanted to try and isolate what was causing the high coolant temps. I knew that if I did everything at once, It would be difficult to pinpoint what piece or pieces had the most impact on the temp.
Since I was fairly certain the high temps were mostly caused by the fan clutch, I decided to separate the two repairs.
After the fan clutch was replaced, temps went to normal and stayed there.
So the fan clutch was 100% the problem. Strange thing about it though is that the clutch seemed fine according to conventional wisdom. It engaged and disengaged, I could not stop it with a rolled up newspaper when the engine was hot — yet could stop it easily with my bare hands when the engine was cold. With engine stopped - the fan would spin a couple inchesif i tried spinning it by hand; it did not freewheel and yet was not overly stiff either.
Even when I pulled the old clutch and compared the resistance of the two while turning them in my hands — they felt identical. Nor did I see any obvious wear after 20 years and 400k miles. Dirty yes — obviously damaged or worn out — no.
But alas, the numbers don't lie — the fan clutch was bad.
So day two consisted of reducing the probability of the infamous pink milkshake. I've gone back & forth in my mind about adding an external cooler for the tranny. I even have one that's been waiting on me to use it. Been sitting in the box for about a year now.
I decided I'll use it but first wanted to replace the radiator. I don't see the point in adding a new external cooler to an old radiator.
So I pulled the old radiator out and it actually looks decent. It certainly ran well once I had a new fan clutch. Looking in from the top, the insides are shiny and clean. Outside was a tad grungy though.
I was too lazy to remove the grill so I grabbed a long wobble socket extension and had no issue getting to the bolts.
Here is a comparison of the old "unknown brand" with the new Spectra brand #CU1998 that I picked up from Pepboys for about $103 out the door.
Before installing the Spectra radiator.
Before installing the radiator, I pulled the thermostat. This is where those cheapy HF stubby ratchets come in handy.
I should add that I'm a dumbass and was so consumed by the original thermostat and it's orientation that I failed to notice that there is a wire bracket that mounts to the bolt. I think when I pulled the tstat off, the bracket sorta flopped back onto the bolt. So when I reinstalled, the bracket was in the way but I didn't notice it...like a dumbass.
So of course everything was just about finished and I was pouring in the coolant when I heard what sounded like Niagra Falls under my truck. Luckily I still had the bucket underneath from when I pulled off the tstat.
Lesson learned.
I pulled it all off again because one of the nuts was starting to round a little from the crappy angles and I didn't need that problem again. So I removed everything including the fan so I could get a decent angle on that nut before I rounded it off.
Once I got it all reinstalled, I filled her up with Prestone green antifreeze. Sure I'd like to run Toyota red, but I decided to stay green for several reasons. The previous owner had green in there already and Toyota didn't ship it with red when it was new. Plus I didn't want any chance of mixing old fluid colors. Lastly, it made it 400,000 miles on green — so I figured I was good to go.
Finally got her all put back together. There is one critical step you don't want to forget about here. That is to replace the transmission fluid lost from when the cooler lines were disconnected. I lost about 20 ounces of fluid Andreas's with me crimping the rubber lines to halt the flow.
So once I burped the system and made sure nothing was leaking, I took it out for a spin. Coolant temp parked itself at 190 while driving with the A/C on max.
As before, I waited until the truck was fully warmed up and then sat idling with the a/c on max and marked the time & temps.
Started at 5:40pm with an outside air temp of only 93 degrees. (Not the 99-100* from before, but it will have to do for now.)
After ten minutes the coolant temp went down to 188*. It had actually gone down to 188* with in 1 minute of idling and it never moved again.
The most interesting thing was that the original thermostat was placed at 1 o'clock by the factory, and I verified that it let the truck idle in 99* air temps with the A/C on — at 186*. When I replaced the thermostat with an OEM Toyota one, it actually went up by two degrees to 188*
Splitting hairs I know, but interesting none the less. One possible explanation for the increase by two degrees is that in the fan clutch test, I used straight distilled water and in the final test, I used 70/30 antifreeze mix.
Regardless though, it's all working as it should.
izza::rockon::biggrin2::rapture:
