The Thetford 42036 is the OEM replacement seat and cover assembly for Thetford Aqua-Magic Style II RV toilets. This is a round, closed-front seat made of durable plastic in white, designed to match the original equipment that came with your toilet. The assembly includes the seat, cover (lid), all mounting hardware, and hinge post for a complete, straightforward replacement.OEM Thetford
The Aqua-Magic Style II is one of Thetford's most popular RV toilet lines, featuring a hybrid ceramic bowl on a polypropylene base. Over time, the seat and cover can crack, discolor, or develop a loose fit from worn hinge hardware. This replacement assembly restores a solid, wobble-free seat with fresh hardware. No special tools are required – just remove the old mounting nuts and swap the assembly.
This seat (42036) fits Aqua-Magic Style II toilets built before May 2015. If your toilet was manufactured after May 2015, you need Thetford 42178 (white) or 42179 (bone) instead. The hinge post design changed and the seats are not interchangeable between the two production periods. How to check: Look for the production date on the data label on the back or underside of your toilet, or compare the hinge post style to your existing seat.
This seat and cover assembly fits the following Aqua-Magic Style II toilet models (built before May 2015):
Note: This is a white seat. It will work on bone-colored toilets listed above, but the color will not match. For a bone-colored seat, see Thetford 42037.
1. Remove old seat – lift the hinge post covers (if equipped) and remove the two mounting nuts from the underside of the toilet bowl rim 2. Remove old bolts and hinge post – pull the old hardware up and out from the top 3. Position new seat – align the bolt holes with the mounting holes on the toilet bowl 4. Install hinge post – insert the hinge post and thread the bolts down through the mounting holes 5. Install washers and nuts – place washers on the bolts from the underside, then hand-tighten the nuts 6. Snug the nuts – tighten until the seat is firm and doesn't wobble, but do not overtighten (plastic threads can strip) 7. Test – open and close the seat and lid to verify smooth operation and stable seating
Clean the seat and cover with Thetford Aqua Clean® or a mild non-abrasive cleaner. Avoid bleach, harsh acids, and abrasive household cleaners – these can damage the plastic finish, cause discoloration, and degrade the toilet's seals over time. Periodically check the mounting nuts for tightness, as RV vibration during travel can loosen hardware.
Note: Seat dimensions match the Aqua-Magic Style II toilet bowl, which measures 15" wide × 20" deep. Both high profile (17-7/8" seat height) and low profile (12-1/8" seat height) toilets use the same seat assembly – the difference is in the base, not the seat.
Before May 2015: Use this seat (42036 white / 42037 bone) After May 2015: Use 42178 (white) or 42179 (bone) The hinge post design changed in May 2015. The seats are not interchangeable between the two production periods.
Thetford Corporation (Airxcel) Ann Arbor, Michigan