So I had my F2 head serviced because it has been running hot and everything else has been replaced. I got up and running today and it still is running hot. Saw a post to better burp the system loosen up the sensor to let out the air and it was better. When I had the head done I put in a new sensor in the back port and moved the old sensor to one of the ports on the t-stat housing. Both vacuum ports are broken off. When the gauge was high I connected the front sensor and the gauge was much lower. I know its only a range sensor but don't really want an after market dash gauge either. Could this just be air getting trapped after a good amount of time? Any thoughts?
Head temp sensor hot (1 Viewer)
- Thread starter Chris Rapp
- Start date
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CaptClose
SILVER Star
I'm trying to follow exactly what you have going on.. but it looks like you have 2 temp sensors, but only one hooked up at a time.
The engine will always be hotter at the rear where the stock sensor is located, than it will be at the thermostat housing. So what you experience was normal.
The best thing to do is to use an IR temp gun and take multiple readings at various locations. 195* is normal. 210* to 215* when you're running hard. You may creep up to 220-225 if you're running AC, 3800 RPM's and the outside temp is in the 90's
If you get above 225* start watching your gauge closely.
The stock thermostat should open partially at 190* and fully at 212* to regulate temp. But coolant quality, radiator and WP efficiency, all play a part.
The engine will always be hotter at the rear where the stock sensor is located, than it will be at the thermostat housing. So what you experience was normal.
The best thing to do is to use an IR temp gun and take multiple readings at various locations. 195* is normal. 210* to 215* when you're running hard. You may creep up to 220-225 if you're running AC, 3800 RPM's and the outside temp is in the 90's
If you get above 225* start watching your gauge closely.
The stock thermostat should open partially at 190* and fully at 212* to regulate temp. But coolant quality, radiator and WP efficiency, all play a part.
I would get over the idea about not having a aftermarket temp gauge.... but thats your call. You really need to know the reading in "F" as to what the engine is doing. Also if the temp sender is not submerged in liquid its not going to read temps correctly, thus you have to get the air out of the system.
Seems like a lot of folks never change their thermostat or the related gaskets/rubber washer either.
Get the air out of the system (cooling system) and then make the call on what the truck is doing with respect to temps and the factory gauge...
Seems like a lot of folks never change their thermostat or the related gaskets/rubber washer either.
Get the air out of the system (cooling system) and then make the call on what the truck is doing with respect to temps and the factory gauge...
- Thread starter
- #4
ya I only hook one up at a time. got the air out I think and running the ac @ 95 ambient temp the need goes up to top quarter, turn off ac and it takes a long time to come back down. Running the heater cools it off pretty good. New t-stat and o-ring tested good in a pot of water. New water pump, new fan clutch, radiator only 5 years old. looks like to at least throw a gauge in to see what it runs at. Not sure this matters now but with colder ambient temp it wouldn't heat up very well.
- Thread starter
- #5
so ran it this morning only 70 degrees out and couldn't get the needle past half way running ac. Parked it in my driveway at a 30 uphill grade and let it idle and it started to go high again, as soon as i drove it though the temp dropped back down. So if its normal to run 225 with ac in the 90's what should I expect when its 110+ out? Thanks
CaptClose
SILVER Star
Hey man... sorry. Let me clarify a bit for you. It would have been better for me to say: it wouldn't be abnormal for you to run at 225* on a hot day, with the AC on, and running hard at a full speed.
Right in the middle is where you want to be. Around 195* is the comfort zone for the 2F. So I think you were fine.
You will always run hotter when parked and idling because there is no airflow to the engine. So that was normal too. I think your fine where you're at. Everything you've told us is completely normal.
I've never driven on a 110 degree day, but it should be no problem based on everything you've told us. Your thermostat, fan, and water pump will keep you in range.
Right in the middle is where you want to be. Around 195* is the comfort zone for the 2F. So I think you were fine.
You will always run hotter when parked and idling because there is no airflow to the engine. So that was normal too. I think your fine where you're at. Everything you've told us is completely normal.
I've never driven on a 110 degree day, but it should be no problem based on everything you've told us. Your thermostat, fan, and water pump will keep you in range.
- Thread starter
- #7
Hope so. This has been a problem even for my parents since the 1990's. We used to change everything almost every summer or so. Will not be funny if it's only a gauge issue.
- Thread starter
- #8
So installed temp sensor. Had to put it up front gecause the probe was too long but just trying to see what it's at. rasily 220 before I turned on the heater. What good places to get 4 core radiators. Radiator.com or others.
- Thread starter
- #9
What you think of the cruiser corps alluminum 3 core radiator?
Here is the short story. In the summer with A/C off, the truck should run on or near the temp of the thermostat _+5 degrees or so. with A/C on the truck would generally run in the 205-215 range _+ 5 degrees or so. Again if you are taking measurements from a different area...there is going to be some variation in the temp range. Don't worry about how the truck cools off once the engine is shut off. Make sure the radiator is in good shape and does not have mud or crap in it and also make sure you don't have anything blocking the air flow between the radiator/condensor and or in front of or in the condensor or radiator....its sound generally like you are ok.
http://www.autozone.com/cooling-hea...ator/spectra-premium-radiator/352698_233208_0
this is the radiator I run with my v8 swap.
this is the radiator I run with my v8 swap.
- Thread starter
- #12
Ya I've been getting a lot of rusty crap out of the radiator. Spent a lot of time trying to clean it out when the head was at the shop and it seems nonstop rusty brown crap.
- Thread starter
- #13
Was hoping to upgrade some because we will be pulling a trailer in the summer too.
take the time to flush out the radiator...and engine. Never run 100% water, always run 50/50 water/coolant. Need to get the "brown crap" out...
I've had the noted radiator above for about 5 years now....its a bolt in direct replacement, no fitting issues and it works and seems well made to me. It is expensive but that generally is part of the deal with LC crap....due to the low production runs of the parts. I like the "old school" 4 core brass tank type radiators over many of the other options I see.
- Thread starter
- #15
I've flushed system multiple times. Finally think I have it good and fill it with 50/50 and several weeks later it's rusty mud again. Such a headache. That model is a 4 core? Couldn't find that info description.
yes mine is a 4 core, Rock Auto carries the same radiator at times, it notes 4 core. Stock OEM factory radiator was 4 core (can't get that anymore though). If you get that one....make sure to get a matching radiator cap. I've had good service out of my radiator as noted, I did buy another one, new for a spare as I got concerned one time that they might stop making these things. I made a couple of mods to mine, but that relates to the GM V8 engine.
There are other radiator optons out there, but I'm not sure there are any other 4 core brass tank OEM type replacements anywhere though, other than this.
1986 TOYOTA LAND CRUISER 4.2L L6 Radiator | RockAuto
don't know if this link will work...rock auto shows to have some in stock. Spectra premium....see description... I'm looking a 1986 FJ60 for reference.
don't know if this link will work...rock auto shows to have some in stock. Spectra premium....see description... I'm looking a 1986 FJ60 for reference.
CaptClose
SILVER Star
I went with the CSF 2708 radiator. I believe it's a 4 core as well. It's a direct fit into a 60/62
micruz60
Unleaded Regular
Yea to the CSF.
One idea about flushing, use a diluted dishwasher (cascade?) mix for a semi-corrosive cleaner?
I have read about using a muriatic (mild) solution as well, but to run it for 100 miles and flush it all out, and be sure to use the block drain as well as the radiator drain.
hth
One idea about flushing, use a diluted dishwasher (cascade?) mix for a semi-corrosive cleaner?
I have read about using a muriatic (mild) solution as well, but to run it for 100 miles and flush it all out, and be sure to use the block drain as well as the radiator drain.
hth
- Thread starter
- #20
I got a new radiator and flushed out the system and same problem. Runs at 220. Replaced t-stat again but noticed the top rubber gasket didn't really hit the upper housing without the housing gasket in place. Think this pass by could cause a problem? doubled up the rubber gasket to try but really don't know what's going on. lots of crap done and no closer to the solution. Still runs hot. It's only 100 out. Pulling my hair out.
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