Diesel Data: Automotive Repair

Thermostat - Replacement Recommendations

84ford13 Article No. 84-5-18-S

THERMOSTAT (6.9L DIESEL) - REPLACEMENT


LIGHT TRUCKS 1983-84 E & F SERIES

This article is being re-issued to present illustrations of acceptable and non-acceptable replacement thermostats.

Figure 25:




Figure 26:




Replacement thermostats other than the specified Motorcraft or International Harvester thermostats may result in engine overheat damage. The specified thermostat (Figure 25) does not contain an internal by-pass, since a by-pass with an integral check ball is located in the cylinder block. If the technician installs an aftermarket thermostat with a "will fit" design that has a flat washer secured to the power pill (Figure 26) the thermostat will block off a water passage, causing engine overheat and possible damage.
Therefore, whenever the thermostat is replaced, it is mandatory that only the specified Motorcraft E3TZ- 8575-A or International Harvester 1803357 C91 thermostat be installed.


PART NUMBER PART NAME CLASS

E3TZ-8575-A Thermostat A


ARTICLE SUPERSEDED: 84-5-18
WARRANTY STATUS: "INFORMATION ONLY"