The car has never had cooling issues before, though it sat in storage the past 5 months. On its first real trip, after it was fully warmed up, sitting at idle for ~60 seconds caused the temp gauge to creep up. Luckily this didn’t happen in real traffic, and when I noticed the temp gauge creeping up towards 3/4 I killed the engine and let her cool for a few minutes. When I got moving again and especially back on the highway, there was no issue. [Ambient air temp only ~65]
I have a helms manual and have pretty much gone through their troubleshooting guide (identical to the G2IC sticky). There is sufficient coolant, the core is not blocked or restricted, the thermostat appears to be working properly (upper rad hose gets hot when engine is hot), fan is working and operating with no cracked blades or anything. Not really sure how to test the rad cap though.
Ideas? Coolant mix hasn’t been changed in 5+ (maybe much longer) years… can it sludge up and loose its cooling capacities?
is this with or without a/c on?
do the fans kick on when they are supposed to?
Was with a/c off… fan works but too much; often will stay on for 20+ min after I shut the car down. Separate issue though.
–
Hopefully this will be much easier to fix than I had thought. I took a better look at the coolant overflow reservoir and its actually more or less bone dry. Between the reservoir being really filthy and some shadows from the surrounding components, I thought I had seen a fluid level much higher than what was actually there… going to do a full drain/flush/refill tomorrow, hopefully that should do it. Not sure where the coolant has gone though- radiator doesn’t seem to have any leaks and doesn’t drip or leave puddles. Guess I’ll find out
-> When refilling the rad, do i do so through the filler neck that the radiator cap covers, or is there a separate neck somewhere?
Fill the radiator through the hole for the radiator cap. When it doesnt want to take anymore coolant, turn the car on and put your climate control to Heat, and put the blower to full blast. This will open the heater core and make sure you get the coolant system completely full. After it cycles a bit and you top it off… Put the radiator cap on, and let the radiator pressurize like normal… Kill the car and let the radiator cool. Pop the cap and top it off again. This method seems to work well for me.
Hope that helps.
Thanks, it did.
As I was filling and bleeding the system, I filled up the overflow reservoir to MIN (as the engine was cold), as well as the radiator filler neck itself to full capacity. Even after a grueling road test, not a drop more of coolant ever made it to the reservoir… there was no overheating and temps were fine, but I feel like the coolant level should rise when the motor is fully hot. This is especially important because without the extra coolant there, my system has only taken 4L of 50/50 as opposed to 5 (what I believe to be stock capacity).
→ Any possible diagnosis’ other than the radiator cap being bad and being too stiff to open up?
because the cap allows coolant into and pulls coolant from the reservoir, there should not be any “extra” coolant in there. it should stay at relatively the same level after the car is shut off
What I meant is that the level of coolant never rose in the overflow reservoir (thus decreasing in the radiator itself), possibly due to an overly stiff radiator cap preventing it from leaving at .9BAR like it was designed. Clearly the overall amount of coolant in the entire closed system was not going to magically increase, but it was my understanding that after reaching a certain pressure in the system, the cap opened internally to let some of the antifreeze chill out for a while. I could easily top off the overflow tank for the whole system to hit its 5L capacity, but my concern is that the coolant isn’t cycling in the system the way that it was designed to, and the coolant in the reservoir will just stay there forever due to the rad cap or another failing component.
Should I expect the level in the overflow tank to rise after a beat run, or do I have nothing to worry about and should just top off the overflow tank?
you do want to have the overflow tank topped to it’s max line. this is done so that the system doesn’t take in any air when it’s “breathing”
btw, i meant nothing by the quotations in my previous post
What I’m wondering though is if the system is breathing as it should or not. Since some fluid goes into the overflow to cool off during a beat run, I would expect the level in the reservoir to be higher immediately after the car has been driven hard for a while (I could be completely wrong). When refilling the rad, my service manual says to top off the rad, add the rad cap to go on a run and let the system pressurize, and then to top it off again afterwards- however, the radiator was still filled to the brim and the reservoir was still basically empty.
Because the level in there was exactly the same as when I filled it to the MIN line initially myself, I’m not sure that it is breathing correctly, maybe due to the rad cap spring being corroded and stiff and not opening as it should. Because the cap is only like 15 bucks I will probably replace it anyways, but thoughts?
is it still overheating, after the flush? if not, i’d just leave it. it’s the pressure placed on the system by the cap which raises the boiling point. if that pressure didn’t exist, you’d probably be overheating
not overheating at all… ill replace the rad cap, top the system off, and forget about it
do what you like. i always say, if it aint broke, don’t fix it. it can sometimes lead to other problems (i.e. buying a faulty cap)
but whatever helps you sleep at night. glad it’s all tickity boo now
cheers