My Ranger has been running hot, so I decided to flush the radiator again. This time, I had much better results.
Normal for my truck should be at the left end bar of the normal range. That is where it would be when I first bought the truck.
I started by looking at the fan clutch. Mine is original and may need replacing. But since I have to order one, I figured I would do some tinkering first. These things are pretty neat. Here is how they work:
http://www.haydenauto.com/upload/HaydenAuto/Documents/Cat_Hayden/Fan_Clutches_How_They_Work.pdf
After that, I found an article describing how they could be rebuilt.
http://oppositelock.kinja.com/how-to-rebuild-your-cooling-fan-clutch-1661694405
I may try the rebuild after I fix the radiator if the clutch does not kick in. What I did was make sure the little thermostat in the center was working. I wire brushed off and then soaked it in PB Blaster for a while. I then twisted it with pliers to make sure is would turn and then heated it with a heat gun to make sure the spring turned the valve. All of this checked out.
So now it was on to the radiator. I have flushed this thing a few times in the past few years. I finally figured out that the rust in my cooling system is because my reservoir did not work. It was sucking air in and there lies the problem. Armed with this knowledge, I am now prepared to do away with this problem for good.
Rust....
So I rigged up a way to flush with the garden hose. Simple, but effective.
I pulled the petcock out because my drain is clogged. Look at the crud on it.
I decided to blow air through the drain to help unclog it....
After seeing all of this stuff, I got out a block of wood and while flushing the radiator, I banged it off of the wood to loosen crap. I got a lot of rust and I seemed to get a bunch of larger crap out of the drain corner of the radiator.
I am confident now that the radiator will function better. But I am not done yet. I decided to soak the radiator in CLR (calcium lime rust). As I had the radiator soaking I noticed on the back it said "Do not use with..... aluminum" ****. So I drained the radiator back out. The CLR was in there about 5 minutes and nothing else came out. I think white distilled vinegar is the better soaking agent here.
Now it is time for the flush. I need to get the rest of the rust out. I found a product called Evapo-Rust Thermocure. From everything I could find, it is almost a miracle product. I figure my Ranger is a good test. I ordered a bottle from Amazon (because of prime shipping), but Summit has the most reviews and a video. http://www.summitracing.com/parts/sum-tc001/overview/"
I saved a sample of the coolant in a mason jar. I will save a sample of the Thermocure when I remove it and I will compare with a new jar of coolant. Should be interesting to see. I can tell you the coolant I saved looks very similar to the coolant drained from the Corvette in the video.
https://youtu.be/mzmgPYqjXd8
I added the bottle of Thermocure and added distilled water to fill the system.
It says it can be left in for several days if there is a lot of rust. I put it in alst Thursday and will remove it tomorrow.
Here is what the concentrate looks like going in. It is a little viscous but doesn't smell bad. It is mostly clear.

After running for a little bit, I noticed that it will make a little bit of foam.
I topped it off with distilled water and closed the radiator cap and took it for a drive. I ran it pretty hard to see what I could get the temperature to do. This was as high as I could get it.
I am certain the radiator flush had something to do with this. I let it sit over night and drove it to work the next day. One thing I did notice is that the truck responds to temperature changes much quicker now. Going up a long hill I could watch the temp climb a bit. Going back down a hill, the temp came back down much quicker. I have yet to hear of feel the cooling fan kick in. I checked yesterday and the clutch only got up to 135. From what I gather, they typically don't kick on until 170. I may throw the top fan shroud back on to see if that also helps. I thought it was only there for safety, but that may not be the case.
I took a little sample of the coolant on Monday. I can't see into the radiator to see how much rust has dissolved, but by the color of this fluid, some definitely has....
I will flush it all out tomorrow and fill it with coolant. Hopefully it will be smooth sailing from there.
Today I ordered some parts from Rock Auto for a few projects. For the Ranger, I ordered the flywheel, friction disc, rear main seal, and pilot bearing (if needed). Sometime in the near future, I am going to pull the tranny back out and change those. I also need to patch an exhaust leak on the wife's car and do her rear brakes for inspection. I also am installing longer wheel studs on her car. We got a set of aftermarket wheel because the stock ones rusted until air leaked. The new aluminum wheels are thicker and the lug nuts seem to like to cross thread. I am sick of dealing with it, so I ordered 20 new longer studs and a stud installer tool. Hopefully that will solve the problem.
