RATTLES: I drive alot on Mexican washboard roads and cobblestone streets and these conditions have shaken apart the three 100 series I have owned down here. So I am constantly tightening and replacing missing parts. My most recent rattle repair cost a cartridge of high quality caulk, and two hours of easy work - no special skills or tools needed. After tolerating an engine hood rattle for long time I started by adjusting the two posts at front corner by manually screwing them in or out as needed to remove play, and remain aligned with fenders - no improvement to the rattle. Gently striking the outside surface of the hood sheet metal, discovered the source. The Araco built 2004 model, as we all know, are bulletproof - but after 17 years baking in the sun, the adhesive caulk Toyota uses to attach this sheet metal to the hood frame underneath has changed from flexible cushion to solid, rigid carbon. These pieces of hard carbon fall into the hood frame channels and rattle and sound like a snare drum. On this hood frame are over 40 locations where Toyota placed the original adhesive caulk to secure the hood skin. The following steps resulted in a major noise/rattle elimination:
1. Remove the insulation pad under the hood. When removing the 12 plastic holding pins, they are near useless, so buy some aftermarket pins with large retaining rings to use upon completion. Note: avoid the 400% mark up at Autozone and find them at your local hardware store.
2. With a bright colored crayon or colored electrical tape, mark the +40 wide sections of the hood frame where Toyota placed the original adhesive caulk. This will help you find thes spots when your caulking gun wants to keep flowing from one spot to the next.
3. Try to remove as much of the carbonized caulk as possible, but some will remain. Not a big concern as the new caulk will tighten this potential rattle up.
4. You want to pump in a healthy amount of caulk at each of the 40 spots. To make these easier use a strong putty knife, broad flat screw driver or specialed pry tool for pulling your interior panels. Do not apply too much force to avoid damage to your outside hood surface. When you remove the pry tool, your new caulk will be pressed into new location, and hood skin will be bonded to your hood frame.
5. After caulikng all +40 locations, leave the insulation pad off, and hood remain open for 24 hours for the new caulk to cure and bond properly.
6. Re-install the insulation pad, close the hood, and try the gently pounding of the hood again. MAJOR IMPROVEMENT, and +40 rattle points gone! Repeat every 10 years or 100,000 miles - whichever comes first!
Caulk used: FLEXTEC Polymer by Henkel/Resistol, but any quality silicone gasket maker will work. Do not be concerened with caulk overruns and crayon markings on this job because all work will be covered over by the insulation pad.
1. Remove the insulation pad under the hood. When removing the 12 plastic holding pins, they are near useless, so buy some aftermarket pins with large retaining rings to use upon completion. Note: avoid the 400% mark up at Autozone and find them at your local hardware store.
2. With a bright colored crayon or colored electrical tape, mark the +40 wide sections of the hood frame where Toyota placed the original adhesive caulk. This will help you find thes spots when your caulking gun wants to keep flowing from one spot to the next.
3. Try to remove as much of the carbonized caulk as possible, but some will remain. Not a big concern as the new caulk will tighten this potential rattle up.
4. You want to pump in a healthy amount of caulk at each of the 40 spots. To make these easier use a strong putty knife, broad flat screw driver or specialed pry tool for pulling your interior panels. Do not apply too much force to avoid damage to your outside hood surface. When you remove the pry tool, your new caulk will be pressed into new location, and hood skin will be bonded to your hood frame.
5. After caulikng all +40 locations, leave the insulation pad off, and hood remain open for 24 hours for the new caulk to cure and bond properly.
6. Re-install the insulation pad, close the hood, and try the gently pounding of the hood again. MAJOR IMPROVEMENT, and +40 rattle points gone! Repeat every 10 years or 100,000 miles - whichever comes first!
Caulk used: FLEXTEC Polymer by Henkel/Resistol, but any quality silicone gasket maker will work. Do not be concerened with caulk overruns and crayon markings on this job because all work will be covered over by the insulation pad.