Engine - Coolant Loss to Extend Afterboil

Bulletin No. T 86-73
File in Group 6B
Number 12
Corp. Ref. No. 616201R
Date July '86
SUBJECT: HT4100 ENGINE COOLANT LOSS

MODELS AFFECTED: 1985 AND 1986 DE VILLES AND FLEETWOODS


Some 1985 and 1986 De Villes and Fleetwoods may experience engine coolant loss due to extended afterboil. Extended afterboil should occur only during high ambient temperatures following driving the car under a heavy engine load (such as driving up a steep hill), and immediately shutting the engine off but before it has cooled to normal operating temperature. After stopping the engine, the coolant temperature continues to increase causing coolant to boil and flow into the overflow reservoir, and under extreme conditions, through the overflow tube to the ground. As the cooling system relieves pressure, it is normal for some gurgling/splashing sounds to be heard from the area of the coolant reservoir.

To correct this condition, a larger coolant reservoir (P/N 25528889) should be installed. This reservoir has an additional 1.1 quarts capacity and will reduce the potential of coolant flowing from the reservoir overflow tube should extended afterboil be experienced.

For warranty purposes, use labor operation J3260 at .4 hour.