Diesel Engine - Valve Spring Retainer Update
84mitsubishi01SUBJECT:
DIESEL ENGINE VALVE CHANGE
NO. STB-84-09-007
DATE September 1984
MODEL 1984 Diesel Engine
VALVE RETENTION SYSTEM CHANGE To make diesel-engine valve spring retainers and locks interchangeable with those on gasoline engines, the diesel engine intake and exhaust valve stems were changed in shape in May, 1984, effective with engine No. AP5108
PARTS INTERCHANGEABILITY A new-design valve may be used to replace an earlier one only if the valve and retaining parts are changed as a set (valve, valve spring retainer, retainer lock). Old and new parts are compared below.
PART NAME PART NUMBER
NEW OLD
Intake Valve MD083661 MD050100
Exhaust Valve MD083662 MD050101
Valve Spring
Retainer MD066498* MD008761**
Retainer Lock MD061895* MD008760**
*Interchangable with 1.8, 2.0 and 2.6L gas engines. **Fits 4D55 Diesel engine only.
FIGURE 1:
DETAILS OF CHANGE Figure 1 shows a side-by-side cutaway view of the old and new diesel engine valve stem, retainer and retainer lock shapes. These differences are shown enlarged in the three illustrations on the next page.
FIGURE 2:
Figure 2 is an enlarged view of the valve stem. The new design (left) has a rounded groove: the old design has a square groove.
FIGURE 3:
Figure 3 is a cross section of the new and old valve spring retainers. Note the new retainer has a funnel-shape depression; the old one has a flat-bottomed depression.
CAUTION
BE CAREFUL NOT TO MIX NEW AND OLD PARTS!
FIGURE 4:
Figure 4 shows the valve retainer locks in cross section. The new retainer has a rounded cross-section to match the round groove in the new valve stem.