Hey Guys. After some clogging/cooling issues I replaced my t-stat...previously I put in a 180 degree, this new one, I went back to original 203 degree, but I can't remember where the gauge read at normal operating temp with the 203, so I can't tell if truck is still running a bit warm or not.

 

Running warm. Centre line is about 210. Mine runs just a bit under centre. I have the 203 stat. Just recently replaced. Tested it in a pot of boiling water and thermometer before putting it in. In the truck My OBD reader varies very slowly between 200 and 215, and the temp gauge plays just a little right about the middle line.
It is possible that your heat problem is the fan clutch not fully engaging. Perhaps replace the fan clutch. $65 part. Or may be dirty rad fins. Full of fuzz and bugs.

 

Well, I had a slight puncture losing coolant for the past 6 months or so...I finally tried to fix that with alumaseal powder leak sealant, and THEN all of a sudden had cooling issues. After monkeying with it last night and today I am 99.9% confident that it is the radiator.

 

Well, pouring goop maker in to fix a leak rather than fixing the leak is a big no no to never ever do. That is probably your issue for the whole cooling system now. You will need to use a strong detergent with hot high flow from an external now to flush/clean that stuff out of there. The rad, the water pump, the engine, your new thermostat, all are now coated with that gunk. The repair has gone from a leaking hose replacement to now an entire cooing system cleaning and recharge. You can expect more leaks and repairs of pump seal replacements after you've cleaned it.

 

 

All is not lost. Just a lot more work, time, and cost to get it back. You will need to soak and circulate with a product such as this. Then drain and thoroughly rinse. Refill with water, and do it again with the product. Drain, thoroughly rinse, then recharge with coolant. Any leaks that show up afterwords .... fix the leak by parts replacement. Never ever dump any "sealer" type stuff in your cooling system (nor any other part of the truck that weeps or leaks!). Manage the leaks by monitoring fluid levels and topping off ; until you have time and funds to replace parts to fix properly. You were perfectly on track managing the leak, then made the mistake of gooping the whole system instead of replacing the single part that was leaking.
As stated. Expect the water pump to leak afterwards. You may get lucky and it is ok and lasts awhile. Probably not, so don't be surprised and be prepared to replace the pump or just the seal. PS: the thermostat and the rad cap both will also be wrecked. After the cleaning procedure is done, replace it with a new ones.

That little 10$ bottle of magic elixir quick fix .... Just cost you about 150$ to 400$ in fluids and parts, as well as an entire day (6 - 8 hours) of cooling system service/repair

Mistakes made. Lesson learned? Get it sorted out, recover, move forward.

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