What is the underhood insulation made of?

I was given an underhood insulation kit from my friend who wrecked his XJ and never installed it. Its the insulation pad from teamcherokee.com, still in the box.

http://www.teamgrandwagoneer.com/cgi-bin/partsSQL/search.cgi?query=hood+insulation&catid=95


I was going to install it in my XJ for the heck of it but my grandfather keeps telling me I shouldn't. He claims it is made of fiberglass and small particles and dust from it can be breathed into the cab. Hes an old car guy, but I'm not sure if this is true for the cherokee pad? What is it made of?

they do more then quiet things down, IIRC they are designed to help smother a fire aswell as protect the hood paint from heat damage

nw-xj-scott said:

they do more then quiet things down, IIRC they are designed to help smother a fire aswell as protect the hood paint from heat damage

Click to expand...

I have heard people say that and I just don't believe it. It is listed in the FSM as a silencer pad no metion of fire suppressant. By the time it would take for those large plastic retainers to melt and drop the pad youre jeep is toast, it's not going to smother a fire, just add to it.

So would this thing be bad news to have in there? I got it for free and its still in the box, brand new. I've been thinking of ways to quiet the engine ticking but don't want to chance breathing in fiberglass. Maybe I could sell it?

I'd use it. If you're worried about dust, you could try hosing it down to rinse off any loose particles.

Imho.., the underhood insulation is crap! I agree that the concept of it somehow being a fire safety device is a long reach. Tore it out of my new '79 Cherokee, model 17, the same day off of the lot. That 258 straight six never distorted/ruined the paint in any way. That said, my recent purchase of a '89XJ came with it already removed! Saved me the time and hassle of removing it cleanly, i.e., the glue, fragments, etc. The thought that the '89's hood paint would be compromised without the insulation being there is a moot point in the idea to have a mostly anti-reflective surface from sunlight glare by my having sanded, and using rattle can primer, several coats of flat black paint, and topped off with a couple of coats of satin clear coats to 'armor' the sub layers.., blah, blah. What I really like about not having insulation under the hood.., is that I CAN HEAR the engine, and can get an early jump on diagnosing any squeal, ticks, tocks, clanks, and etc., before things snap, crackle, or pop. Think about it!?! If you want a quiet ride.., get a Rolls Royce, lol!!!!! Me, I'd send that insulation back to the company, and ask for credit for something you really need. Just some thoughts...

My 01 was missing one from the factory.

My paint is completely cracked, and looks horrible. Crows feet/snowflake cracks all over.

I recently added on from a 96- xj from the junkyard, it seems to keep the hood cooler. Use it.

The 4.0 is a hot motor.

Here's some more reading on this topic from just a couple weeks ago.

http://www.naxja.org/forum/showthread.php?t=1054702