I am not giving up on leaking heater core. I keep with the secondary thing
. Replacing the heater core is a simple solution for a simple problem, which does not fit the business model
Improving the cooling on our TJs
- Thread starter TexasTJ2004
- Start date
I am not giving up on leaking heater core. I keep with the secondary thing
. Replacing the heater core is a simple solution for a simple problem, which does not fit the business model
Complex as it is, I like the secondary loop for the heater core a lot more than rolling the dice on a garbage aftermarket replacement that'll be leaking again (or worse, completely ruptured) in a year.
Just so you know and all the folks know that are giving you crap, you managed to design and build an almost exact copy of the intercooler system that more than a few of the top name forced induction folks have built for the TJ.
Our Rubican sits and Idles with AC on, for half an hour or more during the summer temps of 115- 120, while in the store while shopping.
We have a Griffin Alloy radiator which the PO installed. No Auxiliary radiator installed.
The thermometer inside says 75-78, the air coming out of the dash is 55 degrees.
Using a auxiliary radiator is a proven way to remove heat from the engine even where standing still.
The one I use is the Ford E350 rear heater core $ 40 from Rock Auto. SPECTRA PREMIUM 94630
The old Jeepster has one installed between the frame rails and the FSJ behind the front bumper.
The heater core pulls so much heat out that in temps below 55 it has to be blocked off thermostat will not open.
A CJ3 heater core could be mounted behind the grill on a TJ. FOUR SEASONS 98478 $36 Rock Auto
We have a Griffin Alloy radiator which the PO installed. No Auxiliary radiator installed.
The thermometer inside says 75-78, the air coming out of the dash is 55 degrees.
Using a auxiliary radiator is a proven way to remove heat from the engine even where standing still.
The one I use is the Ford E350 rear heater core $ 40 from Rock Auto. SPECTRA PREMIUM 94630
The old Jeepster has one installed between the frame rails and the FSJ behind the front bumper.
The heater core pulls so much heat out that in temps below 55 it has to be blocked off thermostat will not open.
A CJ3 heater core could be mounted behind the grill on a TJ. FOUR SEASONS 98478 $36 Rock Auto
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I know that some folks will throw rotten eggs at me, but I came to conclusion that connecting the heater core directly, in a single loop to the engine, is a cheap and simple solution, but it exposes the heater core to all the pressure (up to 18PSI) that can built up in the engine coolant system.
It is the pressure that kills the radiators and heater cores, and it seems to me that the lifespan of the radiator has a reverse correlation with the amount of time that it spent at high pressures.
So yes, let’s say I would go ahead and replace heater core - there are no Mopar heater cores for sale, and aftermarket is either cheap garbage or crazy expensive and does not cool well enough. So, the secondary loop enables me to stick to
Factory Mopar, which with quickseal does not leak if it is a part of non pressurized loop.
In addition the secondary loop is a safe way to add more cooling surfaces wherever I want - if it gets ruptured, then it has 0 impact on propulsion, I will lose heater in the cabin and extra cooling capacity, but
0 damage to engine cooling system.
The cycle of heat up in idle that I see:
Intake manifold starts to heat up from around 150F (after driving), and goes toward 190F. As long is it is under 190F, engine stays under 210F.
Then the manifold continues to heat up but the engine coolant starts to climb as well. BTW, transmission temperature starts to climb as well, even if it is in park and no effort on it whatsover. If I would not have Derale ecooler, I think that my transmission would go into 220F area just in idle.
Then manifold and coolant catch up. At around 231F - same temperature for coolant and manifold.
Then manifold continues to climb and reaches to 237F, while coolant stayed at 231F.
The only way how Intake manifold can be hotter than the engine coolant is if it soaks the heat from manifold or the cats.
When manifold was 237F the idle start to become little rough and I decided to test restart of the engine - I shut down and restarted after less that 40 seconds - the engine barely started, typical to fuel rail heat soak.
So, my conclusion that heat soak from teh exhaust is what is major contributing
Idk if it did much but i put this thermotec heat shield on the underside of my intake when i built my stroker. The pieces have stayed in place perfectly.
https://www.google.com/aclk?sa=l&ai...aAAxWELUQIHSOgA4EQwg8oAHoECAYQFQ&nis=8&adurl=
https://www.google.com/aclk?sa=l&ai...aAAxWELUQIHSOgA4EQwg8oAHoECAYQFQ&nis=8&adurl=
If I would be disassembling the engine and manifolds today, I would wrap the manifolds like crazy. Including the cats.
Use Black satin thermal barrier.
https://techlinecoatings.com/new-exhaust-system-coatings/
Do not use on the cats but on all the rest of the pipes
Easy to apply no need to bake, it cures from engine heat.
After air drying for 24 hours, just allow to idle for about 3 minutes then let it sit for about 15 minute then repeat 3 more times.
Then it is ready to go.
https://techlinecoatings.com/new-exhaust-system-coatings/
https://techlinecoatings.com/new-exhaust-system-coatings/
Do not use on the cats but on all the rest of the pipes
Easy to apply no need to bake, it cures from engine heat.
After air drying for 24 hours, just allow to idle for about 3 minutes then let it sit for about 15 minute then repeat 3 more times.
Then it is ready to go.
https://techlinecoatings.com/new-exhaust-system-coatings/
Oh yea, I definitely noticed how similar it is to a water-to-air intercooler and that he’d have no problem building one for a turbo.
And it’s heat that kills your engine. Imo, your order of operation (current focus) is in the weeds on alternative paths when you could simply do that after changing to radiator. One path brings more risk to damaging your engine than the other. Why risk it?
This thread is broadly titled about improving the cooling system in a TJ that has been overheating. This sets up folks in here to help ensure Texas has buttoned up the basics since doing so usually results in the system improving.
No one said Texas can’t properly design or build things. The responses are a direct result from his refusal to change one of the most critical components that he has on a shelf before going down this alternative path.
I know I mentioned it already, but I just went through this with my mopar radiator being partially plugged up causing me to run hot. I spent three days doing flushes before I drove up to PHX.
I went from seeing numbers like you saw to again having acceptable numbers. That’s why installing the mopar radiator would be my first step if my priority was to lower my engine cooling temps.
Took to some
. On highway, today at 101F here in Houston area, running 80MPH, engine stayed at 204F.
But yes, I need to install my Hayden 2791 and Mopar radiator.
Just a correction - I have never seen my TJ running hotter than it should in other situation than idling with AC on more than 10 minutes
. On highway, today at 101F here in Houston area, running 80MPH, engine stayed at 204F.But yes, I need to install my Hayden 2791 and Mopar radiator.
Today took to around lake Conroe area to see hot it will go.
So, I found a place with little wind from the lake and parked with radiator facing the wind. Amazingly, the engine coolant and the manifold both stayed as 210F. Went for 20 minute hike, came back and still got the same 210F.
The outside temperature was 101F, moist as F.
It seems like even little bit of additional air movement solves the heat in idle problem for me.
The AC always stays as cold as it should, because of the 3 fans in the grill that cool down the condenser properly regardless of engine coolant temperature.
The fan inside the louver helps reducing the heat soak problem - after design engineering kit it became much smaller problem and usually will not be an issue if the intake manifold is not in 200F+ area.
So total of 5 eBay fans will running - 3 in the grill for the AC, one in the louver for the fuel rail and one on the heater core next to the winch.
So, I found a place with little wind from the lake and parked with radiator facing the wind. Amazingly, the engine coolant and the manifold both stayed as 210F. Went for 20 minute hike, came back and still got the same 210F.
The outside temperature was 101F, moist as F.
It seems like even little bit of additional air movement solves the heat in idle problem for me.
The AC always stays as cold as it should, because of the 3 fans in the grill that cool down the condenser properly regardless of engine coolant temperature.
The fan inside the louver helps reducing the heat soak problem - after design engineering kit it became much smaller problem and usually will not be an issue if the intake manifold is not in 200F+ area.
So total of 5 eBay fans will running - 3 in the grill for the AC, one in the louver for the fuel rail and one on the heater core next to the winch.
Took to some
Just a correction - I have never seen my TJ running hotter than it should in other situation than idling with AC on more than 10 minutes
But yes, I need to install my Hayden 2791 and Mopar radiator.
If that’s all I knew regarding your issues I’d typically be thinking thermostat, fan, and thermocure.
But I’ve recently noticed my temp higher in idle even though it’s fine when I’m moving. My radiator is still plugged up with corrosion/scale due to the PO’s neglect. When I unplug the crap it idles well again until it gets chunks lodged again.
For reference, I’m in the AZ desert with high IATs from running the turbo without an intercooler. I plan to do my intercooler experiment soon now that my schedule has opened up. Fixed my friends LG combo washer and my friend John Deer skid steer earlier today, which means I can focus on my things now.
My cats get crazy hot and I’ve been fighting a misfire. I have the hood louver installed, rail and injectors wrapped, heat guard installed, and I wrapped the fuel line near the cats. Replaced the spark plugs this evening and did a compression test (all good there).
Btw, by tracking my EGTs I know there’s a significant difference in coasting up to a light vs being on the throttle even when not in boost. My exhaust is wrapped after the pre-cats and I plan to install ceramic coated manifolds at some point once these evening storms let up… I may wrap or heat shield the manifold we’ll see how things develop. Sadly I don’t have plans to install five fans so I may come off kinda boring (just giving you some shit).
I did therm-cure a year ago.
Every single time drained the block completely.
You can see the first thermocure flush on the right and the last one on the left.
You can how the head looked inside before thermocure flushes, and how it looks after.
My thermostat is a year old, it is Mopar. Works perfectly fine. Fan is also year old, same as a water pump.
However, fan clutch is bad. In idle, the quality of fan clutch is critical.
How is it possible that you get the chances lodged again so fast? Did you ever drain the block completely?
I did drain the block like 15 times, plenty of heavy junk came out, I doubt that this junk can be pushed out in any other way other than fully draining block and flushing with water when the drain is open to take out all the junk.
When my rig was stock, if I would idle for a while in 100F+ with AC on, then it would start running rough, and once or couple of times I got misfires. The heat soak in some extreme cases can cause misfire even on running rig.
Yea I always drain the block I timed myself by grabbing my phone randomly as I dropped down to do the third flush. Took me a little less than 1 minute and 30 seconds and that was with me briefly talking to the camera and messing it up a little. This was using a plug with a 8mm hex key (it doesn’t fall off the extension).
I’ve always flushed about 18 gallons of distilled water (3 gallons at a time) to remove the thermocure. My colors were similar. It smells like fish but it works well.
Yes I always drain the block. My cooling system was absolutely jacked when I bought the rig. It worked great when I left for training in NY, but apparently it degraded while I was away even though it was 50/50 G05.
I was not happy when I pulled my radiator cap after seeing the temps just a bit too high in idle. Pulled more chunks out today with a magnet.