I pop the hood when I park in the garage and everything from the prop rod to the air filter box is usually very hot, especially after slow driving off road. Now I realize that this is to be expected, but the heat coming out of the engine bay is definitely hotter than any vehicle I have owned before. I also noticed this is the only vehicle I've owned that has weatherstripping sealing the sides of the engine bay in addition to the leading edge of the hood and the firewall.

My question was if this weatherstripping on the side of the engine bay could be contributing to the high underhood temps. So I pulled the weather stripping off the sides and found it does a few things.

1. The engine bay is definitely cooler after normal highway driving. The airbox is cool, the prop rod isn't so hot, and the plastic covering the battery box is a lot cooler.

2. After slow off road driving, the engine bay is still pretty hot, but the airbox and prop rod seem a bit cooler but I don't have an temp sensor to know the exact reading.

3. The upper fenders get hot from the hot air escaping from under the hood, especially when driving slow off road. With the weatherstripping, they don't seem to change temp at all.

So my question is, is there anything that could be adversly affected by doing this? Has anyone else tried this?

BTW, my fan clutch is brand new and the temp gauge never indicates the motor is getting hot.

 

This is 100% normal for a all aluminum engine.
As we all know aluminum dissipates heat very efficiently.

My hood will get so hot you cant touch it but the engine temp never gets over 215*F.

 

anyone ever put vents in the hood? Out here its common to have 105 plus days when we are wheeling. It really made a difference on some of my other trail rigs.

 

Id like to do something to help the engine cool even if its just a little bit. Maybe Ill remove the weather stripping. Id put some vents if it didn't make it look G.

Maybe Id put some vents in the top of the hood when I do the hood blackout.

 

i'm bidding on a used H2 hood louver on ebay...its black plastic...no handles....

i think i could install it and black out my hood..


i worry about water getting under the hood though.....would prolonged water exposure hurt my D2's electrical stuff?

BTW dont bid on my H2 hood thing lol

 

There are a few ways to do this. there is header wrap which some people use and a some ceramic coatings , one called jet-hot is another. They have been shown to reduce underhood temps from up to 70%. There is some who say header wrap can make headers fail so do some research before trying any of these.

Good luck, Chris

 

I have made the same observation on my D2 and it really freaked me out.

I am most likely going to have my headers ceramic coated when I do the ToddCo 5.0 HO motor swap in about six months or so.

 

All Disco engine compartments have run hot with our V-8 engines cause the original build design was for a 4 cylinder diesel and there was plenty of air flow.
The weather strip is not the problem, it is limited air flow.
The only thing the excess heat damages is our plug wires and I doubt we can ever cool it down so it is cooler to the touch.
One thing that does help a little would be to use a product like water Wetter or Purple Ice, it help help the engine disapate heat better but then there is still the issue of getting rid of that hot air.
Have all you D2 owners removed the plastic shield from under the front of your trucks, this will help some.

 

That's what removing the weatherstripping does, it increases airflow. Try touching the fenders after trying this, there is a lot of heat escaping. I may remove the plastic sheild, you mean the one by the oil filter right?

As far as the vents, they would definitely help, jeep guys do this all the time. Jet hot would help as well, but the heat still wouldn't have anywhere to go unless it was vented.