I've noticed puddles or brownish / orange'ish water in my garage under the FJ40 for a couple weeks and decided to figure out exactly what was leaking and get it fixed. I knew it was coming from the top of the engine and having previously had the upper radiator hose split on me I was wondering if there was some strange trend (at this point that was the newest hose, but seemed most likely from where the water seemed to be coming from). So, I got a pressure tester and pumped it up.
This is going to be a little more involved than a new hose.
Deciding to get it all sorted out at the same time, I ordered new radiator hoses, new heater hoses, new thermostat and gaskets. And, a decided to take a gamble and ordered a cheap aluminum radiator from amazon that included a fan and shroud (I'll let you all know how that part of it turns out). I have never had issues actually overheating, probably mostly due to Western Washington weather (almost never over 80 degrees F), and didn't feel the need to make sure I had a good 4 core radiator. Really have had more issues with it running cold too long after starting, not vaporizing fuel properly when first starting, and having to leave it running to warm up 5-10 minutes before it decides to make enough power to drive. And was hoping a thermostat controlled electric fan could help that.
After draining the antifreeze out of the radiator drain (nice that it's tall enough to just stick a 5 gallon bucket under it) I flushed the whole system with fresh water. Tried flushing it with vinegar, put two gallons in, topped off with water and drove around until it was hot for 10-15 minutes, drained that and flushed it out with fresh water again. Not sure that did much, but was only $6-7 in vinegar and felt safe dumping that without having to collect and properly dispose of.
As I began tearing things apart I discovered the radiator support wasn't bolted down. The support rods were there, bolted down properly, and the two nuts were in the bottom of the radiator support, going into the frame, but there are no nuts on the bottom of them...
Getting prepared for the job, as far back as two weeks ago, I started spraying Kroil oil on the thermostat housing bolts. I've tried using this stuff before, but always on with limited success due to not really giving it a chance, find a bolt that feels rusty, spray it on and expect instant results. This time, I prepared with it. And both those bolts came out in one piece!!! They looked rusty and old, still going to be cleaning up the threads with a tap and buying new bolts.
Once getting the thermostat housing off and thermostat out I found this:
Someone's excessive use of RTV? I've seen a few bad examples of how poor a mechanic the PO was, but I dunno how they managed to get that to fall apart like that inside the engine.
And then I noticed this:
Looks like my thermostat housing has a threaded hose for another thermostat, do they all have that? And I already have two installed in the head (one for the dash gauge and another for smog control that's unused). But a hose looped back on itself. Seems like something that needs more fixing!!! Does anyone happen to know what size thread that is? (I've seen older threads mention 1/2 inch BSP on the head?)
And with all the antifeeze drained and a roll of new heater hose, I finally am taking the opportunity to remove the rear heater (doesn't seem to do much with the top off).
This is going to be a little more involved than a new hose.
Deciding to get it all sorted out at the same time, I ordered new radiator hoses, new heater hoses, new thermostat and gaskets. And, a decided to take a gamble and ordered a cheap aluminum radiator from amazon that included a fan and shroud (I'll let you all know how that part of it turns out). I have never had issues actually overheating, probably mostly due to Western Washington weather (almost never over 80 degrees F), and didn't feel the need to make sure I had a good 4 core radiator. Really have had more issues with it running cold too long after starting, not vaporizing fuel properly when first starting, and having to leave it running to warm up 5-10 minutes before it decides to make enough power to drive. And was hoping a thermostat controlled electric fan could help that.
After draining the antifreeze out of the radiator drain (nice that it's tall enough to just stick a 5 gallon bucket under it) I flushed the whole system with fresh water. Tried flushing it with vinegar, put two gallons in, topped off with water and drove around until it was hot for 10-15 minutes, drained that and flushed it out with fresh water again. Not sure that did much, but was only $6-7 in vinegar and felt safe dumping that without having to collect and properly dispose of.
As I began tearing things apart I discovered the radiator support wasn't bolted down. The support rods were there, bolted down properly, and the two nuts were in the bottom of the radiator support, going into the frame, but there are no nuts on the bottom of them...
Getting prepared for the job, as far back as two weeks ago, I started spraying Kroil oil on the thermostat housing bolts. I've tried using this stuff before, but always on with limited success due to not really giving it a chance, find a bolt that feels rusty, spray it on and expect instant results. This time, I prepared with it. And both those bolts came out in one piece!!! They looked rusty and old, still going to be cleaning up the threads with a tap and buying new bolts.
Once getting the thermostat housing off and thermostat out I found this:
Someone's excessive use of RTV? I've seen a few bad examples of how poor a mechanic the PO was, but I dunno how they managed to get that to fall apart like that inside the engine.
And then I noticed this:
Looks like my thermostat housing has a threaded hose for another thermostat, do they all have that? And I already have two installed in the head (one for the dash gauge and another for smog control that's unused). But a hose looped back on itself. Seems like something that needs more fixing!!! Does anyone happen to know what size thread that is? (I've seen older threads mention 1/2 inch BSP on the head?)
And with all the antifeeze drained and a roll of new heater hose, I finally am taking the opportunity to remove the rear heater (doesn't seem to do much with the top off).
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