Spare tires are important parts of the car, and replace the wheel is an important prerequisite jack accessory spare tire . Xiao Bian learned that many drivers do not know how to use the jack, but do not know in the wrong place using the jack will bring great damage to the vehicle .
" Jack can generally be divided into the rack jacks, screw jacks, hydraulic jacks and inflatable jack four. Family car jack with the more common is the rack jacks, because it has a light weight, small size for easy storage advantages. However, due to limited support weight , it is usually with a family car one ton in weight around . " Mr. Jiang said senior automotive engineer , manufacturers generally will be equipped with the appropriate models based on the weight of the jack . General car jack with load in less than 1.5 tons , and off-road vehicles due to the larger self , which is equipped with jacks can usually load about 2.5 tons . Therefore, a large car jack must not use small cars to avoid security risks when servicing vehicles.
It is understood that the current popular traveling by car enthusiasts in a pneumatic jack, it is the use of the vehicle 's exhaust to inflate the air bag , generally support the weight of the largest of these jacks at about 4 tons , suitable conditions are dangerous rescue or SUVs self-help and rescue .
Vehicles must be parked before using the jack
" If you do not completely fixed before the vehicle support from the vehicle , then support the process , probably because of the vehicle sliding phenomenon caused by falling once the car from slipping off the jack , causing damage to the tool or secondly , if the result in vehicle maintenance personnel injured on Taibuyinggai . " Jiang said the engineer .
According to reports, the proper use of the jack requires a parked car , pull the hand brake , manual transmission car linked into a block or reverse gear , while the automatic car needs linked into the P block . After the jack must be on a hard , flat pavement , if it is relatively soft ground , such as dirt or sand road , before using the jack pad is recommended to use wood or stone and then operate the jack below , reducing the pressure to prevent jack fell into the soft ground inside .
Error will damage the chassis anchor
Many owners have never personally used or replacement spare tire , but did not carefully read the vehicle manual describes the use of and support points on the jack .
According to reports, the underbody has a dedicated support jack anchor , the anchor family cars are usually on the inside of the side skirts , like two sides of the fin chassis , behind the front wheel 20 centimeters in front of the rear wheels 20 centimeters. This channel fin is prominent in the steel chassis can withstand relatively large pressure , if the jack plate supported on the chassis , it is likely to cause unnecessary damage to the chassis. In addition, the support arm in the suspension of the hem is also incorrect operation if the vehicle fell off the jack slip , chassis and jack will suffer.
Many family car jack arm is sub-structure , and the need for supporting the wrench and rotate the sleeve connection , so in the process of lifting jacks , force should be uniform , avoid excessive or too much force . Source: Automotive repair and maintenance