Unit Converter

Hello, everyone. Just a quick post today.
I found this neat little unit converter and thought I would share the link.
You need to have Java loaded on your computer.
Download from the link below. The converter will come up in a small window.
It will convert units for anything you can think of, and it's very easy to use.

Java unit converter link


Thanks for checking this out, soon I will be posting on an ABS problem.
Bruce

General principles of diesel fuel injection diagnosis

This overview follows the VEHICLE diagnostic process outlined in an earlier post:

First - law #1 :  Make sure the simple, cheap, easy things are right before moving on!
V: a VISUAL check is the first step.
E: check the EASY things next.
H: HOOK up a scan tool for problems on a system monitored by the ECM.
I: ISOLATE the problem to a smaller area within the system.
C: CHECK each item only once.
L: the LAST action is to always verify the repair.
E: EVERY problem has a simple solution.*
*simple doesn't necessarily mean easy to find. And rarely a problem may have multiple causes. But most difficult problems are simple ones hiding behind layers of distraction.

• Always do a visual inspection before a diagnostic attempt is made. Check for fuel and oil leaks, loose or disconnected wires or connectors, holes or splits in air-to-air components, a plugged air filter, and make sure there is fuel in the tank. Quite often a problem will be something simple, and this step will save time and effort. Especially on HEUI engines, check oil level and smell for fuel. This step will also help determine if you are dealing with a fuel system problem or some other issue. For instance, a low power complaint can often be found to be a split boot or loose or broken clamp in the charge air system.
• Check for codes, even if the engine light isn't on. Even a stored code can give a clue to the problem, but you can’t repair merely from code information.
• Check filters. Spin off the primary filter and dump it into a clean container to check for water and contaminants. If it is empty or very low on fuel, there may be a restriction or leak between it and the tank. 
• Don’t bother running the engine on ether, as all this proves is that the engine has some compression. If the engine was running recently, you already know that. If a HEUI system is run on ether with a low oil level, the high pressure oil pump will be damaged.

• Check the fuel pressure with a gauge. You must know you have fuel pressure to spec, with no air, to proceed with diagnosis. The fuel pressure check is one of the main tests to do to confirm or eliminate a fuel problem causing a no start. Many wiring and sensor issues can cause a crank but no start.
• Check for air being sucked into the system. You can install a piece of clear hose in the return or remove the return line somewhere and run it into a bucket of fuel. An occasional bubble is ok, but a steady stream of bubbles means air is entering the suction side of the system. On a low pressure system you may be able to install your clear hose after the transfer pump, but it must be installed after the suction side. Air can be sucked in a bad filter, loose fittings, pinholes in lines, or a tank pickup tube. Usually these won’t leak fuel but you may be able to pressurize the tank a little and find it.
• On HEUI systems, always check engine oil level. If the oil is significantly low, the engine won’t start. ICP (injection control pressure) must be checked, and typically about 500 psi is needed to start the engine. The only realistic way to check is with a scantool on the datastream menu. Low ICP should set a code, but the problem could be the pump, sensor, or an internal leak like injector o-rings. Sometimes if you remove the valve cover and run or crank the engine a leak can be found. If the harness to the ICP regulator on the pump is disconnected, the ECM will try to run the engine with a substitute value. If it runs, the high pressure sensor or circuit may be faulty.
• On HEUI systems, check for oil in the fuel. If the fuel is black, o-rings on one or more injectors are bad. A high engine oil level with fuel contamination is bad injector o-rings or injector. 
• On light duty vehicles especially, smell the fuel when you remove a filter. Drivers sometimes don’t want to admit, remember, or realize that they filled up with gasoline. 
• To get any further than this, you must know exactly how the particular system works and what each component does. For some problems a wiring diagram will be needed. You also need to know when to give up and seek professional help. Replacing parts and hoping to get lucky can easily cost more money than paying a shop to fix it.

  Thanks for reading, keep watching for an upcoming post on ABS

 Bruce

fuel system problem diagnosis part 2

       Hello, all, and welcome to part 2 of diesel fuel problem diagnosis. Last time I covered some of the more common fuel injection systems, now I would like to extend this information to diagnosing common problems.
Probably a good place to start is with some common principles. The most important concept governing a fuel system or any system for fluid delivery is that pressure is not generated by the pump, but by flow vs. orifice size. At a given flow rate, a smaller orifice or opening will increase pressure, and a larger flow rate for a given orifice size increases pressure. Think of putting your thumb over the end of a running garden hose. The ultimate limit of flow and pressure is the pump, where the gear or diaphragm size multiplied by the pump speed limits the flow, and ultimate pressure is limited by the sealing ability of the pump’s components. What this means is that low system pressure is often something like a stuck regulator, and not necessarily a bad pump. A regulator is merely a ball or a washer held against an orifice by a spring. The strength of the spring regulates the pressure in the system.

fuel system check valves/regulators

The three most common general fuel system problems are: low fuel pressure, air intrusion, and flow restriction. The following paragraphs will deal with these in turn.
Check valves should be checked whenever there is a pressure or flow problem not due to air intrusion. It is often surprising what can be found stuck in a valve. Small pieces of the inside lining of rubber fuel hoses, bits of Teflon tape, gobs of silicon sealer, bits of paper, and pieces of plant matter are common. Some check balls are made of a hard rubber-like material, and these can be found swollen and sticking open. Probably fuel additives and gasoline along with age, helps break down the material that lines and other components are made of. System pressure must be checked with a gauge, but on high pressure common rail systems fuel pressure must be checked with a scantool. Many high pressure common rail systems incorporate the transfer and high pressure pumps in one component, making it impossible to gauge the low pressure part of the system, but there may be exceptions.

        Another thing to keep in mind is that a system won’t develop rated pressure if there is air mixed with the fuel, nor will it feed the engine the proper amount of fuel. Air can be sucked in at loose, damaged, or improperly installed filters, loose or damaged lines or connectors, worn primer pumps, and broken fuel tank pickup tubes. If two tanks are present, a malfunctioning diverter tee can empty one tank causing that side to draw air. A vacuum gauge plumbed in to the suction side of the system should draw around 2-4 inches of mercury at idle. Any less means lots of air is getting in, any more would be a restriction. Probably a better way to check for air is to install a piece of clear hose somewhere on the suction side and look for a steady stream of bubbles. On systems that return to the tank, the return line can be extended and put into a bucket of fuel and watched for air. Occasionally an injector will stick open and engine compression will pressurize the whole fuel system with air. Lots of air.

        Flow restrictions are probably more common than air intrusion. Of course, fuel filters should be the first thing checked, but don’t forget the screen or separator type primary filter. Pre-2004 Internationals, for instance, have a small plastic bowl by the spin-on filter that never seems to get cleaned out. Besides plugged filters, nylon fuel lines can be kinked, elbows can collect debris, and the aforementioned check balls can restrict flow if swollen. One thing that can drive mechanics crazy is an intermittent restriction caused by something in the tank that occasionally gets sucked against the pickup, shutting off flow. The little foil bottle seals on fuel additive bottles are famous for this. One sign of a restriction is if the filter is dry or very low after the engine dies. Of course, lots of air getting sucked in could cause the same thing. If you think there is a restriction between the tank and the engine the fuel line can be unhooked at the primary filter and run to a bucket of fuel. if the engine runs now, you know where to look for the problem.

Keep in mind that it is very difficult to diagnose problems with modern engines without good software to display codes and run tests. Even having an active code to give a clue to the nature of the problem is usually only a start. For instance, a common code that could be generated for a no start on a HEUI injected motor could be for low injection control pressure.

      There are numerous problems that could generate this code, including:

• low oil level 

• a worn engine oil pump that can’t keep up with the demands of the high pressure system

• internal oil leaks like broken injector o rings

• a failed ICP (injection control pressure) sensor or bad sensor circuit

• a failed ICP regulator or circuit

• a failed or worn high pressure pump

         More than once I have seen a HEUI engine with significant external oil leaks run low enough on oil that the high pressure reservoir runs out of oil and the engine stops. The owner or a mechanic will then repeatedly crank it trying to get it to start, maybe running it on ether. High pressure oil pumps will not tolerate being run dry for very long, and will soon burn up with this kind of treatment. Oil level must be the first thing checked for a no start on one of these engines, especially with a low ICP code.

Keep watching this site. Next I will outline a general system of diagnosis for fuel system problems, and then I will post on ABS problems.