Engine bay insulation

MasterChiefIDI

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My factory firewall and fender insulation is deteriorated and a mouse nest on my 86 F350 6.9idi. Does anyone have recommendations for what to replace the engine compartment insulation with for fenders and firewall? I will be installing a turbo so feel I def need to add something to the trans tunnel.

Thanks
 

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franklin2

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I use that self stick foil insulation you can get from Lowe's. You will have to decide if you want to use the self stick, or they have some that does not have the self stick and you use the sliver tape. The self stick works well, if you are sticking it to the truck. But if you want to wrap the self stick on itself, they have a release on it when it's rolled up in the store, so it does not want to stick to itself. But they both work well.
 

IDIBOBS

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You can buy the original molded stuff for the engine bay then do the foil dynamat / fake stuff on the inside. Be careful not to use anything flamable under the hood especially near exhaust and turbo. I usually do 3 layers on the floor and fire wall inside under the carpet as well as roof.
 

Old Goat

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"Master Chief", sounds like you were is the Navy for a while.
That nasty looking k rap as shown in your picture, I Removed it and gave it the deep 6, and didn`t replace it with anything.
I removed my inner plastic fender to get to the Oil Cooler a few years back.

That stuff was full of dirt, oil and mouse *** and ??? :puke:
Looks better with it gone, and not sure it really did much as
far as sound. 30+ years of yuck gone.

I did stick on some X Mat or Kill Mat to the Firewall, what I could reach laying over the engine. Was fun cutting off the old
rubbery stuff Ford had attached to the FW laying across the engine with a Razor Blade knife...LOL
Withe engine removed would make it easier.
Wipe things down really well to remove any oil etc...

Use some Carb or Brake Cleaner, it takes off the Kill Mat or X Mat etc... wording.

With the extra Heat of the Turbo etc... not sure how it will hold up. Maybe contact one of the companies that make the stuff.
Maybe they have some for the FW and Tunnel area.

EDIT: OH Darn, another bad word. P E E
Another word to add to my bad word list.

Goat
 
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Austin86250

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Does the killmat style work as good as factory? I’ve always wondered that
I’ve always went to the junkyard for factory style
 

MasterChiefIDI

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Thanks for all the input guys. I'm planning to use DEI's form a shield on the trans tunnel. May put some Kilmat underneath it though.

I am thinking I will leave the fenders on uninsulated. The stuff that's there is just so nasty. Can add something later there.
 

Old Goat

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The things I did to quiet down my 86.
Stripped the Interior and fully scrubbed and washed it out.
Used one of the Harbor Freight air chisels to get the Factory
Tar Pad insulators off the floor. Then wiped it down with Wax And grease remover.

And rust areas wire wheel etc... treated it to POR.
Any pin hole rusted through areas (not structrual) you can use some cloth saturated in POR to bridge it.

I then Dyna-matted the Floor and back of the Cab areas.
Even the inside the doors and front face of the doors.
Installed new P O R N O Red Carpet I got from Rock Auto.
Bought new Door panels and insulated the inside of them.

Replaced the Window Channel and Window Wipes, that there made a big difference in the wind/road noise.

I got rid of the old vynal bench seat with Duct tape and old Blanket I was sitting on.
Found a nice bench seat at PNP out of a F-150 and had it redone in red P O R N O Volure fabric.

I did replace the Door Seals, but the after market ones don`t seem to compress and the doors don`t shut smooth. Stick out a bit.
I was at PNP one day and came across a newer truck, one of those door and half door one`s. Seal looked similar, and is way longer.
Bought both sides. Washed up one in the Bath Tub with hot soapy water to get the years of grime off it.
(Don`t tell my Wife)
Measured it to find center, and started at the top of the door opening, and worked my way around.
At the bottom they overlap, Cut it off at about the center of the seat so the seam wasn`t where you get in and out.

Since these are used, might be best to get the Passenger side as that side doesn`t get used as much. If you go that route.
Also on the inside of the part that fits on the Pinch Weld, is a flap of rubber, I guess fits one inside trim of those years trucks.
I cut it off with a razor blade knife.

I was impressed with the fit, I ordered a new set on line.
If you look at the end of the door seal it is an open tube the door squished against to make the seal.
So were the PNP one`s.

The new one`s I bought (maybe some customer complaints of wind noise?) when you look into the tube, they now have a verticle wall, so 2 chambers to stiffen it up.

Drives side has the old one and Pass side has the new one, and doesn`t compress as well.
But I can talk to my Wife w/o yelling....

I mentioned up above about POR the rusty areas of the floor, and bridging any rusty pin holes areas.
I also on the bottom side of the Cab, wiped it off with Wax N grease remover and sanded it down ant POR it also,
Then stuck some dyna mat over those areas.

I mentioned in above post about Dyna Matting the FW, That was back in July/August when I replaced the Injection Pump & Injectors. Then got carried away and tore it down and replaced Hyd Lifters, Push Rods etc...
So had more access area to the FW tunnel area to rip out the old Insulation.

I have an 85 6.9 extra Cab that was the first truck I tore into and Dyna Mated.
I picked up a roll of insulation stuff at Home Depot for AC Duct think. Has sticky side, and Foam and a tin foil side.
I put this on the back wall and cab sides of the extra part.
Wouldn`t use it on the floor where it get wet as the foam will hold water.



That`s my story, worked for me so far...... :peelout

Goat
 

MasterChiefIDI

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This is helpful. Thank you for sharing. I will take these tips and consideration when I do the interior. My main concern is insulating the engine bay specifically for turbo setup at the firewall side. Don't want the damn pipe heating up my firewall too much and cooking the inside.
 

IDIBOBS

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This is helpful. Thank you for sharing. I will take these tips and consideration when I do the interior. My main concern is insulating the engine bay specifically for turbo setup at the firewall side. Don't want the damn pipe heating up my firewall too much and cooking the inside.
with the factory or similar insulation on the engine side of the fire wall and the dynamat type stuff on the cab side of the fire wall (double thick) and floors and tunnel (triple thick) I have zero motor/turbo heat inside the cab. I also did the roof doors and back wall. Super quiet, doors close like a new car and heat/cold stays out.
 
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