Oil cooling setup for LS Jeep

[Bullitt1]

Wheeled most of the summer which I haven’t done in years but seems as thought I have a little bit of a heat problem on my rig that I’ve been working to correct. I’ve got the run of the mill cammed and tuned LQ9 Jeep TJ on tons , it’s a manual so no trans cooler but I’d like to put together a engine oil cooler and fan setup for next springs visit out west. I’ve got a plate type steering cooler in front of the rad and a single Spal fan that helped along with hood vents but Im sure there’s more I can do. My stainless shorty headers are unwrapped , Is wrapping them worth the effort ?

The real question is what are you running , full filter relocation and cooler or what? I‘d love some CBR ultra4 stuff but that’s out of my price range.

 

[Bebop]

Don't wrap.

Improved racing oil pick up with a 180 thermostat. Filter in the stock location.
AN10 lines.
12x12 radiator in front of the engine rad. No need for a fan.



That said, heat problem usually needs water cooling addressed, not oil cooling. What rad are fan setup are you using ?

 

[Bullitt1]

Don't wrap.

Improved racing oil pick up with a 180 thermostat. Filter in the stock location.
AN10 lines.
12x12 radiator in front of the engine rad. No need for a fan.



That said, heat problem usually needs water cooling addressed, not oil cooling. What rad are fan setup are you using ?

BeCool LS conversion rad with a 16” Spal puller fan and if I remember correctly a 187° thermostat. It’s honestly never overheated but it gets up there and hovers around 205° with 215°+ under slow crawling is the norm. The fan is switched at 220° on and 200° off but it’s not one of Spals high CFM models..think a better fan or rad is beneficial?

 

[cdemart2]

I wouldn't worry until you see 230°. these engines run 220° from the factory all day.

 

[Will Scarlet]

My stainless shorty headers are unwrapped , Is wrapping them worth the effort ?

I agree with Bebop in not wrapping. However, I would suggest getting them ceramic coated. It will help to push the heat down the exhaust line better.

 

[Bebop]

BeCool LS conversion rad with a 16” Spal puller fan and if I remember correctly a 187° thermostat. It’s honestly never overheated but it gets up there and hovers around 205° with 215°+ under slow crawling is the norm. The fan is switched at 220° on and 200° off but it’s not one of Spals high CFM models..think a better fan or rad is beneficial?

Start by installing a Volvo fan with its relay.
Will change your life.

1st speed at 190
2nd speed at 210

Will never overheat again

 

[Bebop]

I agree with Bebop in not wrapping. However, I would suggest getting them ceramic coated. It will help to push the heat down the exhaust line better.

I have not seen any temp improvements with that coating

 

[Will Scarlet]

I have not seen any temp improvements with that coating

I have with a couple of vehicles.

 

[arse_sidewards]

You have a domestic V8 used in truck applications. Ditch the spal and throw a mechanical fan on there with a proper shroud.

180 thermostat.

No, no no.

You want oil to be hot enough water can't stay in it.

That said, heat problem usually needs water cooling addressed

This.

 

[Bebop]

You have a domestic V8 used in truck applications. Ditch the spal and throw a mechanical fan on there with a proper shroud.

In a TJ ? Just put the proper fan and you'll be fine.

No, no no.

You want oil to be hot enough water can't stay in it.

I'm confused.
What would be the perfect oil thermostat temperature for you ?

Bullitt1 : I have installed Volvo fans or helped people installed Volvo fans on multiple cars and Jeep specifically. My friend Marvin (from FlexRocks and Rollovers) is running a soupped up 6.1 Hemi with a single Volvo fan and keeps it around 200 all day long including Sand Hollow crawling / hwy driving etc. It's a great fan.

 

[arse_sidewards]

In a TJ ? Just put the proper fan and you'll be fine.

He didn't say what he was doing with it. If he's just crawling and trail riding and other "mild intermittant applications of skinny pedal" type use then he'll probably be fine with a decent electric fan.

If he's in the sand dunes he's gonna want something with more CFM because the high loads are sustained longer and the lower loads are higher.

Basically the same reason that when GM puts that garbage in a car they put an electric fan in front of it but when they put it in something more work oriented it gets a clutch fan.

The Volvo fan is a fine electric fan but it doesn't come close to a mechanical fan and pretty much nothing will until you start throwing a lot of money around.

What would be the perfect oil thermostat temperature for you ?

200-250

 

[Bebop]

He didn't say what he was doing with it. If he's just crawling and trail riding and other "mild intermittant applications of skinny pedal" type use then he'll probably be fine with a decent electric fan.

If he's in the sand dunes he's gonna want something with more CFM because the high loads are sustained longer and the lower loads are higher.

Sand cars that make 2000hp and trophy trucks that make 1000+ and run wide open for hours on end all use electric fans.
If you size them properly, you're good.

Basically the same reason that when GM puts that garbage in a car they put an electric fan in front of it but when they put it in something more work oriented it gets a clutch fan.

GM has switched the silverados from clutch to electric fans in 2005.

The Volvo fan is a fine electric fan but it doesn't come close to a mechanical fan and pretty much nothing will until you start throwing a lot of money around.

Bullshit. Experience tells me different. Both mine and people that have the same setup. You don't need to throw money around, they cost $75 at the JY.

200-250

Is it 200, 210, 220, 230, 240 or 250? There are multiple options.
Also, why ?

 

[arse_sidewards]

Sand cars that make 2000hp and trophy trucks that make 1000+ and run wide open for hours on end all use electric fans.
If you size them properly, you're good.

Those fan setups cost more than his rig.

GM has switched the silverados from clutch to electric fans in 2005.

Because half ton GM trucks are toys for people like you. The vans still run a clutch fan on the LS at least into the 2020s and all of the big 3 use clutches on their 3/4 ton and larger stuff.

Bullshit. Experience tells me different. Both mine and people that have the same setup. You don't need to throw money around, they cost $75 at the JY.

You spend 30sec on the throttle and then 30min taking photos for the 'gram. A fan off a Yugo (do those even have electric fans? ) would work for you.


When you combine a big engine with a small amount of space for a radiator (like in a TJ) and then use it hard you simply will not get an electric fan to keep up without spending a lot of money. I get that most people drive their wheelers like you and that a Volvo fan is reliably fine for that but since he's already having problems cooling, the degree to which a Volvo fan is an upgrade over his existing one is unclear has plenty of length in that engine bay a mechanical fan is absolutely the easy button here. He can slap one on and never have any question about whether the fan portion of his cooling system is sufficient.

Is it 200, 210, 220, 230, 240 or 250? There are multiple options.
Also, why ?

If you weren't a Reddit engineer you'd know that "hot enough to keep the water out but not so hot that shit starts forming deposits" is a pretty wide range and as long as you're in it it generally (i.e no special circumstances) doesn't matter.

 

[Bebop]

Yawn.

 

[Bullitt1]

I’ve got a buddy who has a ’05 HD Max and had him measure the mechanical fan dia. and depth and there’s no way in hell that things fitting in my TJ without gutting the grill shell and getting a larger rad. and moving it out 3-4” .

 

[HYDRODYNAMIC]

Thermostats of the fluid type come in to play when you have forced air cooling from driving fast or an engine mounted fan. If you have a small radiator or grumpy grill blocking airflow and an electric fan then the fan thermostat switch is what will determine the temp of the engine. Might as well delete the fluid thermostat if it’s a LS and rely on the fan switch to control the engine temps.

I think the OEM mechanical vs electric comes down to HP, TQ and power requirements. Once the heat load goes past a certain point, mechanical is cheaper to run vs huge alternators and huge fans. 4,6,8 cylinder gas engines towing a Uhaul is nothing compared to a diesel hauling an overloaded 50’ 5th wheel rolling coal going up a grade.

 

[gt1guy]

BeCool LS conversion rad with a 16” Spal puller fan and if I remember correctly a 187° thermostat. It’s honestly never overheated but it gets up there and hovers around 205° with 215°+ under slow crawling is the norm. The fan is switched at 220° on and 200° off but it’s not one of Spals high CFM models..think a better fan or rad is beneficial?

That sounds like a fine running LS engine, temp wise.

I'm a big fan of engine oil cooling. After all it's the oil that cools the entire rotating assembly. As said already, the oil does need to get up to a temp where the moisture will evaporate out of it.

How hot is your oil getting now?

 

[Bullitt1]

That sounds like a fine running LS engine, temp wise.

I'm a big fan of engine oil cooling. After all it's the oil that cools the entire rotating assembly. As said already, the oil does need to get up to a temp where the moisture will evaporate out of it.

How hot is your oil getting now?

I agree that 205° is right where a LS should be I’m just uncomfortable with the temps flashing up and down and regularly bumping 240 before the fan can catch up. I’m guessing this is prime example of a insufficient system but it’s what I’ve got room for , the rad. was actually a Mishimoto 3 core conversion unit which seemed to have a good reputation. I‘m not monitoring oil temps now but I had planned on the oil cooler circuit being thermostatically controlled and adding a gauge.

 

[gt1guy]

My pile isn't running yet, but I went with a 205* thermostat in my remote filter mount.


If your maxed on room for the radiator, maybe look into moving more air through it as Bebop mentioned. You can also lower the temps that it kicks on/off to help stay in front of dumping a bunch of heat into the rad.

 

[Rockwood]

He didn't say what he was doing with it. If he's just crawling and trail riding and other "mild intermittant applications of skinny pedal" type use then he'll probably be fine with a decent electric fan.

If he's in the sand dunes he's gonna want something with more CFM because the high loads are sustained longer and the lower loads are higher.

Basically the same reason that when GM puts that garbage in a car they put an electric fan in front of it but when they put it in something more work oriented it gets a clutch fan.

The Volvo fan is a fine electric fan but it doesn't come close to a mechanical fan and pretty much nothing will until you start throwing a lot of money around.


200-250

Stock high embeddability OE bearings start to get soft at 250*F, and really gets pissed at 275*.

You don't need the water to boil out of there right fucking now, you need it to evaporate quickly. Water isn't hanging out long at over 180*F. Keep in mind the thermostat open temperature isn't the maximum temperature of the oil, just where it starts to open. Oil temps around 200*F are perfectly fine.

I agree that 205° is right where a LS should be I’m just uncomfortable with the temps flashing up and down and regularly bumping 240 before the fan can catch up. I’m guessing this is prime example of a insufficient system but it’s what I’ve got room for , the rad. was actually a Mishimoto 3 core conversion unit which seemed to have a good reputation. I‘m not monitoring oil temps now but I had planned on the oil cooler circuit being thermostatically controlled and adding a gauge.

Set the fan on speed for lower then. 210*F on, 200*F off would be about right.

 

[gt1guy]

You don't need the water to boil out of there right fucking now, you need it to evaporate quickly. Water isn't hanging out long at over 180*F. Keep in mind the thermostat open temperature isn't the maximum temperature of the oil, just where it starts to open. Oil temps around 200*F are perfectly fine.

When the oil gets pushed up on top of the heads and spends a little time sloshing around the valve springs and sitting on top of the exhaust ports.......it's gonna get plenty of heat into it. It's also a great place to have the water vapor to leave the oil since there's direct access outside the engine through the valve covers.

 

[chaplinfj60]

Start by installing a Volvo fan with its relay.
Will change your life.

1st speed at 190
2nd speed at 210

Will never overheat again

i agree. i have done one also..... with one twist...
i used my computer to set the temps the fan turns on. i think low speed turns on at 160 or 180. i stay in low speed 90% of the time. nd high speed comes on around 205 i believe.

 

[Rockwood]

i agree. i have done one also..... with one twist...
i used my computer to set the temps the fan turns on. i think low speed turns on at 160 or 180. i stay in low speed 90% of the time. nd high speed comes on around 205 i believe.

x3. Kept my stock radiator XJ cool-ish (it is an XJ after all) at 90*F and 7,000' in the mountains. it got to 230*F once that weekend: racing a buddy back up to camp, 3000' climb, floored or hard on the brakes for 15 minutes straight. AC set to max, winch and 2 coolers in front of the puny Autozone special XJ radiator. Other than that monkey business, most of the trip you could watch the thermostat cycle. Jeep is used as a dune recovery vehicle dragging broken buggies and SxSs out from Glamis, etc, etc, etc. Does just fine.

Upgraded to a C7 Z06 Vette fan for the LS swap, mainly to be more efficient. Still have it sitting here, yours if you're close enough to SoCal.

 

[Bebop]

You don't need the water to boil out of there right fucking now, you need it to evaporate quickly. Water isn't hanging out long at over 180*F. Keep in mind the thermostat open temperature isn't the maximum temperature of the oil, just where it starts to open. Oil temps around 200*F are perfectly fine.

Nope, arse disagrees with you so you must be wrong.

Other than that monkey business, most of the trip you could watch the thermostat cycle.

That's not ideal either. When you have your fans running full time, and the thermostat closes and opens to maintain temperature, you're creating hot spots in the engine and then dumping cold water in when the thermostat opens.

Much better too have your thermostat open around 180 (for an example) and cycle the fans to keep temperature around your desired operating range. I usually shoot for 190/200 for an LS based engine.

C7 Z06 fan is the business. Run it with a real PWM signal and you'll be amazed by the consistancy of the temps. Spal out-did themselves with that brushless line-up.

 

[Bullitt1]

x3. Kept my stock radiator XJ cool-ish (it is an XJ after all) at 90*F and 7,000' in the mountains. it got to 230*F once that weekend: racing a buddy back up to camp, 3000' climb, floored or hard on the brakes for 15 minutes straight. AC set to max, winch and 2 coolers in front of the puny Autozone special XJ radiator. Other than that monkey business, most of the trip you could watch the thermostat cycle. Jeep is used as a dune recovery vehicle dragging broken buggies and SxSs out from Glamis, etc, etc, etc. Does just fine.

Upgraded to a C7 Z06 Vette fan for the LS swap, mainly to be more efficient. Still have it sitting here, yours if you're close enough to SoCal.

One of these…what’s rough outside dimensions on the unit?

 

[RustyC]

Late to the party here but. I have have had nothing but a good experience using Volvo fans and LS engines. They are like standard issue shit around here. The pcm is what makes it so easy. Fan cycles as needed without worry.
Hell I had a low speed relay fail and the pcm was simply switching on the high side as needed. I never knew it until I heard the fan go from off to high speed. Rode the rest of the day and made repairs when I got home.
Shit just works man.

 

[Bebop]

One of these…what’s rough outside dimensions on the unit?

More complex install with a PWM signal than what you want.
But yeah that's the fan. About 17" in OD

 

[Rockwood]

Nope, arse disagrees with you so you must be wrong.



That's not ideal either. When you have your fans running full time, and the thermostat closes and opens to maintain temperature, you're creating hot spots in the engine and then dumping cold water in when the thermostat opens.

Much better too have your thermostat open around 180 (for an example) and cycle the fans to keep temperature around your desired operating range. I usually shoot for 190/200 for an LS based engine.

C7 Z06 fan is the business. Run it with a real PWM signal and you'll be amazed by the consistancy of the temps. Spal out-did themselves with that brushless line-up.

Nope, but I'm using dumb temp switches on the stock Jeep 4.0 engine management. Fans don't run full time, but they do turn on at slightly below thermostat temps, and are on the output hose of the engine. When the thermostat closes, the fans turn off a minute or so later. Not ideal, but gotta piss with the cock you got.

LS will be PWM control with an external controller (P59 ECM won't control PWM), so dialing in temps will be super easy.

One of these…what’s rough outside dimensions on the unit?

I have a Volvo/Taurus fan from the JY if someone wants it. The vette fan is staying with me.

But, Vette fan dimms if you're curious:

Fan itself:
14.5" diameter, 3" min depth.

15.5 tall x 21.5 wide x 4.375 deep.

 

[Bullitt1]

More complex install with a PWM signal than what you want.
But yeah that's the fan. About 17" in OD

PWM , like varying fan RPM based on temp? Does it get the signal from the computer or a temp sensor?

 

[Bebop]

PWM , like varying fan RPM based on temp? Does it get the signal from the computer or a temp sensor?

So you bought a C7 fan but haven't looked into how to wire it ? Giving it power and ground won't turn it on.
It needs a speed command signal from the ECU or some sort of PWM signal generator.