Chassis Weep Holes

Drill 1/4” weep, or drain, holes in the bottom of the main chassis tubing. These holes will help keep moisture out of the interior of the chassis tubing that can leak in through rivet holes and other small openings.

The chassis tubes are not coated on their inner diameters, and will rust from the inside out if moisture is trapped for extended periods of time. The purpose of the weep holes is to minimize standing water in the tubes; some surface rust on the tube interiors is inevitable, but is not a safety risk.

Weep holes can also be tapped for a screw cap. If using this method, make sure the cap screws are put in place when the chassis is completely dry. Caps should be removed and checked from time to time. Due to their location under the chassis, weep hole cap checking is inconvenient unless a lift is readily available.

Capped weep hole in the driver footbox dropped floor

Also drill 1/2” holes in the corners of both the passenger and driver dropped footbox floors. Cap holes with 1/2” metal plugs (see part inventory under Home Depot).

When installing insulation and carpet, make sure these caps remain accessible. In the event that the Cobra gets wet (rain storm or other unforeseen circumstance), these footbox drains will facilitate getting moisture out of the cockpit, reducing the chance of carpet mold or rust around rivets.