Engine - Intake Manifold Oil Leaks

Bulletin No. T 85-28
File In Group 6A

Number 68
Date Nov. '84

SUBJECT: HT4100 INTAKE MANIFOLD OIL LEAKS

MODELS AFFECTED: 1982-1985 DEVILLES, FLEETWOODS, BROUGHAMS, ELDORADOS AND SEVILLES

FIGURE 1 - Intake Manifold:

Some Cadillacs equipped with an HT4100 engine may experience an oil leak at the intake manifold to block seal. This condition may be caused by a split intake manifold end seal. To correct this condition, new silicone end seals (refer to Figure 1) were released for production during the 1984 model year. The breakpoints are as follows:
MODEL VIN

1984 RWD Devilles and Broughams 139931
1984 Eldorado 659759
1984 Seville 831723
1985 FWD Devilles and Fleetwoods 213362

To repair this condition on HT4100 engines produced prior to the listed VINs, the new end seals have also been released for service, and will be part of the intake manifold gasket kit (P/N 3634619). This new seal can be identified by its gray color.

The previous intake manifold gasket kit (P/N 3634584) is still available and may be used on repairs if the original end seals were not split.