Which Direction Should the Piston Dot Face on the Buick Excelle?
2 Answers
Piston direction arrows uniformly point toward the timing side. Below is relevant information: Buick Excelle: The Buick Excelle is based on General Motors' global platform. The prototype of the Excelle was the latest globally developed mid-size sedan by General Motors, primarily designed and developed by GM Daewoo Auto & Technology (GMDAT). On April 21, 2003, SAIC-GM launched its new mid-size car, known as the 'Mid-Level Buick' - the Excelle. SAIC-GM officially entered the promising mid-size car market with the grand introduction of the 'Buick Excelle,' based on an all-new product platform. Vehicle Positioning: The Buick Excelle is positioned as an entry-level family car, featuring a dynamic exterior and high-quality interior, offering the quality experience of 'your first car.' The new drive system is smooth and fuel-efficient, while the entire series comes standard with the 10th-generation OnStar all-time online assistant, equipped with an onboard 4G LTE mobile hotspot, utilizing eConnect smart connectivity technology, and supporting Apple CarPlay and Baidu CarLife.
A few days ago I worked on an old Excelle, where the piston dot thing was particularly crucial. For most Buick Excelle engines, that small dot or arrow mark on top of the piston should face the front of the engine, which is the direction of the crankshaft pulley. This is because the dot indicates the direction of the piston's offset weight design—installing it backward would cause the piston to move off-track and wear out prematurely. During disassembly and reassembly, you need to use a flashlight to clearly see the mark on the piston crown, and also ensure the notch mark on the connecting rod big-end bearing cap faces the timing belt direction. This double-check makes mistakes less likely. Last year, I encountered an owner who installed the piston backward himself, and the engine cylinder seized after just 1,000 kilometers, costing him a full engine overhaul for nothing.
