About 225 to 235 in those pics.
FJ62's Overheating. Several of us don't know why. (4 Viewers)
- Thread starter CruisD64
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CaptHamster
TLCA #19645
@OSS I actually used your photos from your gauge calibration thread as a reference, combined with IR gun temps and an old school mechanical water gauge to confirm that my temp gauge is pretty darn close to yours. Temps up to 235 may not be overheating but that can't be good for an old 3FE can it? Of course mine only hit that after a long grade through the desert, highway speeds with ambient temp of about 115 degrees, but still.
Well there is definitely something to the overheating issue, because my truck had all new parts just like the OP, just a couple years ago. Previous owner said it had been running that hot since he had it. And he put all new Everything on just before I bought it hoping to fix it but NO.
That is EXACTLY what my gauge shows as well.
Don't discount the flushing. If there was a previous owner who dumped a bunch of stop leak garbage in there instead of fixing things the right way, you may have layers of grime and goo that is effecting heat transfer. Same for engines that have been run on tapwater, you get a lot of scale and rust.
Good old fashioned vacuum gauge will help you know if you have an exhaust restriction.
If you got a bunch of scale/goop in your water jackets, your heater core is likely gooped up too, but that isn't the case. If your coolant isn't rusty, oily, etc then that's unlikely the problem. It kinda sounds like your head gasket might be partially blocking the jackets, or maybe some gasket sealer/RTV got loose.
Have you tried spraying the garden hose through the rad fins? You might be surprised how much crap collects in there. While you do that, temp gauge should drop quickly.
Have you tried spraying the garden hose through the rad fins? You might be surprised how much crap collects in there. While you do that, temp gauge should drop quickly.
My truck has never had anything but Toyota red, got every receipt to prove it. Coolant looks super clean. It will stay a mystery for now I haven’t got time to add this to the project list
After driving today I‘m 90% sure my fan clutch is bad, as I remember I never had one that would last more than 2 yrs, and all have been Toyota parts.
I recently had an overheating issue on my FJ60, the fan clutch would only act bad when it was at temp which it would then spin freely. I know this is a longshot, but I usually enjoy cooler temps after a fresh oil change. My FSM says the wrong grade of oil can lead to overheating, maybe too much friction with the wrong oil? I dunno.
I would also make sure that all the cooling lines are installed in the correct orientation, don't ask my why i suggest that because I wont tell.
I would also make sure that all the cooling lines are installed in the correct orientation, don't ask my why i suggest that because I wont tell.
Mine hit the 239 mark just as I finally got off the freeway last Tuesday. 113 degrees ambient, AC on, moving at about 75-78 for about 20 minutes. Typically in 100+ conditions like those it would go no higher than shown in the 230 reference pic. Leads me to believe there's buildup in some of the water jackets causing a slight reduction in coolant flow. Fortunately I've never had a full on overheat, but it's still running warmer than I would like in summer temps so I'm looking to correct it before it leads to a more urgent problem.
CaptHamster
TLCA #19645
Post up once you've done that coolant flush, interested to see what your results are. Unfortunately it looks like no shortage of hot weather for us to test things out...
What octane of fuel are you using in the hot weather? Climbing hills increases engine load. Increased engine load makes a engine more likely to Ping. Pinging will increase engine temps. Hotter intake air temps will also increase the likelihood of pinging. If the truck is running too lean this will also increase temps. A few things could be tried. Try reducing the timing a few degrees, increase the octane, have a decent intake setup. A air fuel gauge is also a good investment.
I was thinking of you guys yesterday. It was 102° ambient, my 60 was cruising at 198° consistently with 190° thermostat, AC off, SUP's stacked on the roof rack, taking it easy at about 50 mph. Original clutch fan, CFS radiator. Not rubbing it in, just tossing in a reference.
In my case, since I obsess over ethanol free and 91 octane is the only flavor it's available in here, that's what I use. I have however advanced my timing to take advantage of the higher octane. To do mine I dialed it to the maximum vacuum using a gauge, then back two inHg. Best way to avoid pinging from advancing the vacuum too far. Long hill climbs versus long level stretches make no difference with me, which reinforces my supposition that my case is just an issue of maintenance being due.
If the engine can keep its temps within its normal operating range when traveling full speed on the freeway on a hot day, then the radiator and water pump and coolant flow would be working as they should.
If the vehicle then pulls off the freeway on that hot day and the temps begin to climb while waiting at a stop light or driving slowly in traffic, that's pretty much normal unless the fan clutch isn't working properly.
The engine is blazing hot while driving fast, way hotter than the coolant gets, so when the vehicle suddenly slows down and drives slow, or waits at a stop light, all that hot metal keeps on dumping heat into the coolant - but the coolant isn't circulating as fast any more and the air flow through the radiator is way way less than when driving 65 mph.
On my 60, I always reved up the throttle a bit with either the choke knob or throttle knob or my foot on the gas pedal to get the RPMs up to maybe 1000 rpm while waiting at a stop light after driving fast. It helps keep the coolant flowing faster and the fan pulling more air so the coolant doesn't get too hot
If the vehicle then pulls off the freeway on that hot day and the temps begin to climb while waiting at a stop light or driving slowly in traffic, that's pretty much normal unless the fan clutch isn't working properly.
The engine is blazing hot while driving fast, way hotter than the coolant gets, so when the vehicle suddenly slows down and drives slow, or waits at a stop light, all that hot metal keeps on dumping heat into the coolant - but the coolant isn't circulating as fast any more and the air flow through the radiator is way way less than when driving 65 mph.
On my 60, I always reved up the throttle a bit with either the choke knob or throttle knob or my foot on the gas pedal to get the RPMs up to maybe 1000 rpm while waiting at a stop light after driving fast. It helps keep the coolant flowing faster and the fan pulling more air so the coolant doesn't get too hot
- Thread starter
- #58
Yep. Purchased from Toyota directly. I'll pull the plugs soon. Been drinking a lot this weekend and not paying attention to the threads
I'll be back on it very soon.
- Thread starter
- #59
I do run a shroud. Under the hood mine is as stock as they get. I've changed the vacuum lines and new hoses where necessary. I've not done a proper flush. I picked up some Prestone flushing solution and will be doing that soon. I'm not very optimistic though. The color of my coolant is very green. One detail that may be significant is that my cruiser sat idle for a year with the hoses off while I was getting things together. /shrug. I dunno.
rhah
Admit it, your cruisers jealous
So sounds like a new water pump and fan clutch just to be safe, rock auto for less than 100$
I fought this problem way back in nam, ended up being the head gasket. That 2f cost me almost 3k$ to get it running right, which it does now but for that price I could have v8 swapped it
