Know the sump
before opening it.
The model separates the oil pan, gasket, two factory screw groups and drain plug. Use it to see their relationship and build a record of the hardware on this car. The virtual bolt pattern and pan shape still need direct measurements.
Explore the sump assembly in 3D ↗The factory parts plate B86, PDF p. 61 lists the parts and quantities above for the Midget 1500. It also lists four WL208 lock washers. A later MGOC Midget parts catalog describes twelve short screws, four longer screws at the rear, sixteen lock washers and a different drain-plug stock number. Those catalogs do not prove what is fitted to this 1975 North American car. Photograph and count the installed hardware before choosing parts.
Select a piece
Pan and drain plug
The pan is hollow in CAD so the pickup and drain opening can be understood. Its depth, side profile, boss, plug position and head are estimates. The real plug must be identified from beneath the car.
Select drain plug ↗Gasket
A separate GEG517 ring shows the joint to the block. Its thickness and holes are placeholders, not a gasket cutting template.
Select gasket ↗Twelve MA805 screws
The factory count is documented. The CAD distributes the twelve around an illustrative flange; it cannot tell you where to place each screw on the car.
Select twelve screws ↗Four HU805 screws
They form a separate catalog group. The model groups four at the rear as a comparison with the later MGOC description, pending identification on the actual engine.
Select four screws ↗Measure the pan for an owner CAD build
With the car safely supported, use the flat block-to-pan gasket joint as a horizontal datum. Measure vertically from it to the lowest outside pan floor, excluding the drain boss and screw heads. Measure down from the same joint to the center of the fitted drain plug. For its lengthwise position, measure forward from the rearmost edge of the pan gasket flange to that center. Photograph the view square-on with a ruler, and record whether the drain faces the distributor/alternator side or the carburetor side.
Those three direct dimensions and an observed side can move the lower pan and drain in a separate owner STEP build. The CAD flange length and contour, screw pattern, plug head and thread remain provisional.
Enter joint-to-floor depth in the pan inspector ↗ · Enter drain dimensions and side in the plug inspector ↗
Record before a sump project
- With the car safely supported, photograph the whole pan from each accessible side and the drain plug straight on. Record its head type, size and any marking without guessing from the CAD.
- Count every sump screw and record its position on a sketch or annotated photograph. Note any obscured by the crossmember, clutch housing or other fitted equipment.
- If removal is part of a planned repair, keep screws and washers indexed by their actual positions. Compare lengths and threads only after removal; record whether four positions differ.
- Photograph both gasket rails and the removed gasket with a ruler before cleaning. Check flange straightness and the applicable workshop sealing procedure before refitting.
- With the pan off, photograph the pickup, strainer and pan interior. Measure their real clearance only if it is needed for that repair.
It does not establish access clearance for removing the sump in this car, the true screw centers, a tightening sequence or torque, plug thread, seal, or pan capacity. Follow the applicable factory procedure and the actual fitted hardware for those decisions.