The Bobcat 853 is an efficient Skid Steer Loader ideal for landscaping, ground preparation, construction and site clean up. The loader has quite good specs ranging from a 58 horsepower engine to a tipping load of 1700lb. This article looks at the common mechanical and electrical problems that may ensure during the useful life of Bobcat 853 and the possible remedies.
Table of Contents
Fuel Starvation Problem
The performance of a loader is largely dependent on its engine receiving clean, sufficient gasoline, failure to which, functionality is compromised. Problematic components in the fuel system of your Bobcat 850 may cause the engine to either be deprived of good, clean fuel or fail to run with power and efficiency. Lets look at some of the components which can be serviced, repaired or replaced to solve the problem.
Fuel Pick Up Line
This gas line with a screen at its end goes into the gas tank. The weighted filter on the end of the line is designed in such a way that when you go up hill or down hill, the filter will stay in the fuel delivering gas to the fuel pumps. During hard launches, most fuel will flow to the back of the tank but the pickup tube will pull fuel and feed it forward. The lines are usually rubber and eventually rot and can fall off into the tank.
When the fuel pickup tube is not replaced, your Bobcat 853 is likely to experience fuel starvation problems. The process may prove to be quite complicated, especially because of the awkward location of the tube on this Bobcat model so seeking professional help would be a better option.
Filters
While these components are basic and common, the role they play in your loader is massive. The air filter prevents dust particles, dirt or any kind of debris from entering your engine, while the fuel filter performs a similar function but for the fuel flow. Both play important roles in maintaining a flawless fuel system.
The fuel filter, as per recommendation, should be replaced at 500 hour/12 month intervals. The manufacturer also recommends that after a filter change, air must be purged out of the system before starting the engine. Do this by loosening the air vent plug atop the filter then operating the primer bulb until fuel flows from the vent plug. Repeat this process for the fuel injection pump.
Lift Problem
When your Bobcat 853 bucket is failing to lift or tilt, or when it’s weak and slow, it spells a lot of downtime on your project and that’s a problem. Faulty actuators, insufficient or leaking fluids, ad solenoids are all possible contributors to the lift issue. When hoses and lines are leaking, loss of fluids will starve the hydraulic system of power that it needs to operate at full capacity. Here are some areas to start looking as you troubleshoot.
Spool Valves
Spool consist of a shaft with O-rings in a barrel. They regulate the flow and passage of fluid or air in the pneumatic or hydraulic system. When these valves are exposed to wear and tear, due to a contaminated hydraulic system, the loader my lose power because fluids and air are energy sources.Take the valve apart by unscrewing the housing. You can then use a brush to get rid of any debris or obstructions. It is also important to replace any parts that have been damaged.
Control System
To minimize problems of fatigue, the nature and mechanical setup of Bobcat 853 controls must translate to precision in operation, doing more work in less time. A malfunctioning Controller may contribute to lifting and tilting failures. Checking error codes on display will help diagnose the problem, as well as doing manual inspection to single out loose or damaged wires.
Fluid Sufficiency
Power transmission and energy transfer in the hydraulic system is done mostly by fluids. They also serve as lubricants and sealants. Fluids will flush out contaminants while also cooling cooling the equipment. Insufficient or contaminated fluids reduce pressure in the hydraulic system and cause a problem of weak lifting on the Bobcat 853. Ensure that you do regular checks of hoses and tube lines to detect any leakages. It is recommended that this is done at 50 hour intervals. Replace dirty filters to avoid contamination of fluids and use hydrometer to check if viscosity levels comply with manufacturer specifications.
Hydrostatic Issues
Your Bobcat 853 may develop a charge pressure problem with service code HP2. In some cases, the loader will run but fail to move (even if brake is off). The hydrostatic charge pressure light will turn on and start beeping. While the warning light could just be a false alarm, it does indicate that there may be issues that need attention. Below are some of the areas you want to look into
Hydrostatic Fluid Level
Hydrostatic pressure is determined by the height of fluid, so it’s important to maintain correct levels. Monitor fluid levels using the sight glass. The little red ball inside the sight glass floats in hydraulic oil and if the ball is at the bottom of the glass, it means you are low on fluid.
Operate At Correct RPM
A problem that you may encounter when your Bobcat 853 is running on low RPM is that the engine will not feel as powerful. In addition to this, a high RPM will give the hydraulic system faster recovery time as it works and uses up pressure. It is best to let your dealer recommend the best RPM to achieve maximum efficiency and still maintain hydraulic components in good condition.
Filter
The hydrostatic transmission filter, in its proper condition, must protect transmission fluid from contamination by dirt, debris or metal shavings from gears. Ensure that regular checks are done to clean, blow and flush the filter of all debris and replace it at intervals.
Main Bearing Failure
When your Bobcat 853 final drive motor starts making excessive noise, unusual vibrations or above normal heating, you most likely have a bearing problem. Bearings will succumb to wear and tear over time, but failure to take care of your loader will just cause them to age prematurely. It is important to maintain healthy bearings because they serve the important task of reducing friction and minimizing damage to final drive components.
Check Bearing Oil
Oil in the main hub must be inspected every 500 hours, and changed where there is need. Oil is a lubricant that will preserve bearings by minimizing metal to metal friction. Also ensure that you use the recommended type of oil both in terms of type and viscosity.
Plug Leaks Quickly
Oil leaks in the system will reduce oil levels at an abnormal rate, exposing your bearings to damage even before the 500 hour mark. When ever you see puddles of oil around your skid steer, make thorough inspection inspections and plug leaks in time.
Finally, avoid taking for granted the recommendations and specifications that are given by the manufacturer via service visits and user manuals. Pay attention to your loader’s fluids both for the engine, the hydraulics and transmission. This can prolong the lifespan of your Bobcat and save you from a number of expensive and time consuming problems.