Relocating the radiator

[Jump This]

The idea is to move some weight back and to install a different radiator with electric fans behind the drivers compartment.

Is the stock water pump capable of handling the extra distance the hoses will need to be? It will be located approx. where our C pillar would be.

Would there be any issues with not having any forced air in the engine compartment?

 

[Capt. Nemo]

I'm no fab genius, but moving that little bit of weight back doesn't seem to outweigh the cost and work involved. You're carrying the weight anyway, and then having to add a greater amount of water (weight) to fill the addition length of the hoses. Why not buy a lighter radiator and keep it where it is?

 

[Jump This]

I'm no fab genius, but moving that little bit of weight back doesn't seem to outweigh the cost and work involved. You're carrying the weight anyway, and then having to add a greater amount of water (weight) to fill the addition length of the hoses. Why not buy a lighter radiator and keep it where it is?

Its more of a relocation of weight.
The front 60 will be 6" further forward and the winch will sit further back than
it would if I should keep the radiator in the stock location. Even the batteries will be located behind the seats (and low.)
Its not about costs.

 

[Sponge Bob]

all will work just fine but it will be very warm in the cab with hot air from the rad

 

[nosigma]

He lives in Borrego Springs. He wont notice it unless he uses the radiator as a seat back cushion.

 

[AZXJ]

I've considered the same, Rick. I have a Chevy Aluminum Radiator with Dual electric fans. The biggest problem is routing the water lines to the rear.. The floor starts to get crowded with a cage, and the underside you will run into clearence issues with the exhaust/front driveshaft/long arms/fuel and brake lines.. depending on what side you run the water lines to. + the added in cab heat.. If you are running boat sides running HREW or DOM for water lines might be an option..

Dave

 

[Jump This]

I'm still looking into the routing.
Tell you what, you give me your radiator with fans, and I'll see if I can make it work.



(Doesn't the ZJ have tripple electric fans stock?)

 

[Israel]

I'm still looking into the routing.
Tell you what, you give me your radiator with fans, and I'll see if I can make it work.



(Doesn't the ZJ have tripple electric fans stock?)

The only ZJ I know of that uses electric fans is the 98 Limited with the 5.9L and I believe it uses one large fan. Most of the ZJ fellas who want to go electric use the Ford Taurus fan.

 

[Weasel]

The idea is to move some weight back and to install a different radiator with electric fans behind the drivers compartment.

Is the stock water pump capable of handling the extra distance the hoses will need to be? It will be located approx. where our C pillar would be.

Would there be any issues with not having any forced air in the engine compartment?

x2 All of Twisted Custom's rigs have it in the front and they balance out fine. Not to mention the safety factor of having the radiator away from the driver if it start leaking or is damaged.

 

[FordGuy]

Most off-road race cars run them in the mid section but it creates a couple of issues that are serious. You must be protected in the case of a radiator failure/crash, people forget that you are wearing a race suit and helmet in a race car, it will burn the shit out of you if you get a leak or blown hose. The routing is a pain and acts like you have your exhaust running inside your cab, needs to be tubed underneath and well protected. Purging can also be a bitch if not designed correctly. There has been a lot of people hurt in sand cars due to hoses failing and being strapped in a harness wearing a tee shit and shorts with a 200 deg radiator 12 inches from the back seat!

 

[Jump This]

Most off-road race cars run them in the mid section but it creates a couple of issues that are serious. You must be protected in the case of a radiator failure/crash, people forget that you are wearing a race suit and helmet in a race car, it will burn the shit out of you if you get a leak or blown hose. The routing is a pain and acts like you have your exhaust running inside your cab, needs to be tubed underneath and well protected. Purging can also be a bitch if not designed correctly. There has been a lot of people hurt in sand cars due to hoses failing and being strapped in a harness wearing a tee shit and shorts with a 200 deg radiator 12 inches from the back seat!

All of my water cooled sand cars have the radiator located mid chassis.
This is mostly due to engine location (rear engine) but, sand cars don't often end up on thier sides (and as many of you know, I often end up on my side.)
That is something I'll need to keep in mind.
I have never seen a Cherokee with a blown radiator hose that wasn't overheated or that had quality (and maintained) hoses.
This is going into a buggy build, so cab head is not an issue.
I still think I'm going to look closer into moving the radiator behind the drivers area.

 

[squirrel80]

Give Hesco a call and ask what they think about a water pump pushing the water to the back of an XJ. At the very least they will try and sell you one of their high flow water pumps. I don't think you will have a problem with mounting or cooling if you get an OK water flow. Most of the Off Road trucks I have been around in Baja use a rear mounted radiator and I don't think they use any special water pump, other than a good quality one. I'm pretty sure you have made up your mind on why you want it back there. 1-1/2" Aluminized exhaust tubing works great for custom routing and you can get a muffler shop to make mandrel bends for you. Silicone hose bends are available at Kartek or McKenzies for the ends at the engine and radiator.

http://www.kartek.com/Product/Cooling/SilHoses.html

 

[Jump This]

Its just one of those things I have always felt was they way to do it.
I have been burnt before from hot fluids (oil cooler line) that ended up going
where not intended.
I'm even thinking AN lines to the radiator.
Lets just see what room I end up with after the three link design....

 

[squirrel80]

I'm even thinking AN lines to the radiator.

Not after what you find out what -24 AN Lines and Fittings cost.

 

[Jump This]

Not after what you find out what -24 AN Lines and Fittings cost.

I didn't even want to think about it.
But safety costs...

 

[Clean Racing]

You should be fine with galvanized tube and silicone hose fittings for the cooling system.. I mean really take a look at what a ton of the sand dune crowd does with their 100 grand set ups... No need for AN fittings on the radiator unless you plan on running baja in your XJ-Buggy...

 

[Jump This]

You should be fine with galvanized tube and silicone hose fittings for the cooling system.. I mean really take a look at what a ton of the sand dune crowd does with their 100 grand set ups... No need for AN fittings on the radiator unless you plan on running baja in your XJ-Buggy...

Sand cars don't often end up on thier sides.....I'd bet there is good money on me going over within the first year of these mods hitting the rocks, and its a given I'll end up on my side with in the first week.

But I agree, if I go that way, I'll use 1.50" aluminium and quality rubber (silicone tubes.)

 

[Weasel]

Its just one of those things I have always felt was they way to do it.

From a design standpoint it's not. I know a ton of racers do it and it works but it's not right. Airflow does not flow through the cab area like it will through the front. Also most people never built the correct shrouding to route the airflow either. If you ever look at fluid flow (ie aero design) you'll get an idea of why a front mount is better and no measure of fan is going to pull the air to the degree that it would flow due to aero considerations. Of course this is at speed and slow speed or crawling things change and the aeroa part drops out.

 

[Jump This]

From a design standpoint it's not. I know a ton of racers do it and it works but it's not right. Airflow does not flow through the cab area like it will through the front. Also most people never built the correct shrouding to route the airflow either. If you ever look at fluid flow (ie aero design) you'll get an idea of why a front mount is better and no measure of fan is going to pull the air to the degree that it would flow due to aero considerations. Of course this is at speed and slow speed or crawling things change and the aeroa part drops out.

Not right?
From strictly an engineering standpoint....why?
The system is designed to do one thing, keep the engine at an appropriate
operating temperature range. Modern water cooled engines will operate all day at 220* without any adverse effects.
Any reasonably designed radiator and fan combo will have no problem keeping our little 4 liter engines running at whatever temperature we want them too.
I'm not even building a Baja rig, I'm building a crawler rig that should be able to maintain reasonable speeds across the desert (but probably only 3/4 the speed my sand car will do! Maybe only half what my sand car will do.)
My biggest concern is with routing, the ability for the pump to handle the load, and protecting the radiator (and occupants.) Not so much with the systems ability to handle the job (I'd say that is a given.)

 

[Weasel]

because it's not in the direct line of airflow. Like I said it's not right but it works.

You can run a bigger, rad, more fans, more cfm to compensate for non ideal design.

Sounds like you have already made your mind up and want to do it so go for it.