Novak Conversions Jeep Wrangler TJ engine mounts

Question about heater core removal

bohuggabee

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Oct 29, 2018
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colorado
First off, these pop up ads on my screen make this website almost impossible to use on my phone...

Its a 99 4.0 with the special engine block thats called “the bullet proof engine”

Anyway, a couple years ago, i forgot i used water in my radiator, i just topped it off... and it ended up freezing that winter and when i used the heater, cracked the heater core. I know... im an idiot. It seems to only leak when running because there is no coolant running inside the cab. Its just steam.

So ive just basically refilled the radiator need be, because i only drove 6 miles a day, and never had a garage where i could remove the dash to fix it.

Now, i have to rely on my jeep for an hour of driving, in heavy snow conditions and i need to solve this without a mechanic. No extra money.. i originally got this jeep so i could repair it myself too!

Does anyone have heater core “volumes of fluid” and “pressure specs” for a 99 tj. So i can calculate, If i simply were to bypass the heater core, the pressure in the engine and radiator becoming too great, or if it the overflow tank be able to handle it?!

Also, bypassing the heater core, would cycle smaller amounts of coolant and would that be more acidic on the engine and basically accelerate wear, or cause another internal catastrophic failure?!

Or can i get away with a simple bypass for this winter?! Driving an hour when its blizzarding.
 
People bypass the heater core all the time, and where I live, I go about 8 months of the year where I never run the heater. Bypass it and move on. However, I would not want to drive a vehicle with no heat (or, more importantly, defrost) in the winter!
 
you can bypass the heater core without hurting anything. many on here do it . my question is if your driving in a blizzard or really any freezing situation how are you going to keep the windshield from icing up, stop and clean it every 5 miles...
 
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People bypass the heater core all the time, and where I live, I go about 8 months of the year where I never run the heater. Bypass it and move on. However, I would not want to drive a vehicle with no heat (or, more importantly, defrost) in the winter!

Even in the winter, i dont use the heater. Windows down. Back windows off cause the plastic fogged. But still you didnt really answer my question about coolant pressure. But yes defrost is kind of a must, since the core is leaking, its like a constant defrost.
 
special engine block thats called “the bullet proof engine"

“volumes of fluid” and “pressure specs” for a 99 tj. So i can calculate, If i simply were to bypass the heater core, the pressure in the engine and radiator becoming too great

Also, bypassing the heater core, would cycle smaller amounts of coolant and would that be more acidic on the engine and basically accelerate wear, or cause another internal catastrophic failure?!

I can't decide if you're a troll,an idiot or both.
 
Pressure isn't an issue with a bypass unless it's already an issue...do you have a reason to suspect you've got combustion gasses passing through the head gasket?

Pulling the dash isn't terrible. Weekend project tops.

You also can buy little 12v ceramic heaters.

Probably the reason you've never needed defrost is because it's almost always running. It's the default position for the HVAC system.

Lots of choices. I've had my dash out a couple of times and I'd just spend the time now and fix it. Nothing sucks more than being cold.

-Mac
 
You can bypass short term without affecting the system, but I would repair ASAP so you have functional defrost.

It’s not a terrible job, just stay organized and take notes and pictures as you go.
 
Pressure isn't an issue with a bypass unless it's already an issue...do you have a reason to suspect you've got combustion gasses passing through the head gasket?

Pulling the dash isn't terrible. Weekend project tops.

You also can buy little 12v ceramic heaters.

Probably the reason you've never needed defrost is because it's almost always running. It's the default position for the HVAC system.

Lots of choices. I've had my dash out a couple of times and I'd just spend the time now and fix it. Nothing sucks more than being cold.

-Mac

Periodically, the coolant got low and you smell the “cork smell”... thats why im considering bypass to keep the engine itself safe for now till i can finally repair the heater core. But the gasket may already be bad. Its 160,000 miles. Its been abused. N i suspect vacuum issues elsewhere but the main concern in this post is analyzing a bypass and pressure. If the overflow can handle that
 
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You can bypass short term without affecting the system, but I would repair ASAP so you have functional defrost.

It’s not a terrible job, just stay organized and take notes and pictures as you go.

You can bypass short term without affecting the system, but I would repair ASAP so you have functional defrost.

It’s not a terrible job, just stay organized and take notes and pictures as you go.

Jeep engineers are notoriously unpredictable too. Took me about an hour to remove the fuel line for new injectors. Cause i had to figure out how to modify and craft a jig. In the end i just use a screw driver. Bent the fins and rammed them back into place
 
Pressure isn't an issue with a bypass unless it's already an issue...do you have a reason to suspect you've got combustion gasses passing through the head gasket?

Pulling the dash isn't terrible. Weekend project tops.

You also can buy little 12v ceramic heaters.

Probably the reason you've never needed defrost is because it's almost always running. It's the default position for the HVAC system.

Lots of choices. I've had my dash out a couple of times and I'd just spend the time now and fix it. Nothing sucks more than being cold.

-Mac
My jeep windows have been off for years... its open air now. I wrap my face in a scarf and wear war grade wool gloves if im desperate. I can walk in sub zero weather without socks on in canvas shoes. People slashed my windows, the old plastic windows fogged... so i just took it all off. Its just my doors, and i often roll down the windows cause it isnt a problem.

I just have trouble knowing if the bypass would add extra pressure in the overall line.
 
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but the main concern in this post is analyzing a bypass and pressure. If the overflow can handle that

The system doesn't have any idea if the heater core is plumbed in or not. If you need to bypass it, do so, and then get the fluid level right just like you would otherwise. There is no special magic here.
 
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On a related note for those who live in cold climates and are having heat issues, I bought this last week
https://www.amazon.com/dp/B0D59BKY7K?tag=wranglerorg-20
for my TDI which takes forever to generate heat in the morning and after a week of use I can say it works great, I'm no longer shivering in the morning on the cold simulated leather waiting for heat, this thing heats up in about 1 minute. It's even UL listed.
I don't like to wear a jacket when I drive, besides it gets warm here by 10:30 or 11 so the jacket would end up flung in the back seat and forgotten anyway.
 
On a related note for those who live in cold climates and are having heat issues, I bought this last week
https://www.amazon.com/dp/B0D59BKY7K?tag=wranglerorg-20
for my TDI which takes forever to generate heat in the morning and after a week of use I can say it works great, I'm no longer shivering in the morning on the cold simulated leather waiting for heat, this thing heats up in about 1 minute. It's even UL listed.
I don't like to wear a jacket when I drive, besides it gets warm here by 10:30 or 11 so the jacket would end up flung in the back seat and forgotten anyway.

yea but do you have windows and doors ? Santa Claus (aka the OP) has no windows or doors on his Sleigh so even if he had a working heater core it would do no good to keep him warm. his brain has undoubtedly suffered severe/irreversible frost bite 🤪 🤪🤪
 
Anyone know what's going on in here?

If your heater core is leaking and you don't want to replace it, just connect the heater core hoses together, bypassing the heater core all together. If everything is working correctly otherwise, it'll work fine. If that's what the OP is asking. I'm not certain.

Personally, I would just replace the heater core. It's not hard. Just takes some time to get the dash out of the way.
 
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Novak Conversions Jeep Wrangler TJ engine mounts