geordi wrote:
Couple things:
The original fuel head design can cause leaks and fires. You don't need the fuel heater at all unless you are in the arctic. Unplug it, as it is NEVER OFF otherwise. Dumb design.
Make sure your filter is tight, and that you only have ONE of the center gaskets in place. Sometimes they stick when removing the filter, and having two on top of each other makes a good seal impossible.
The plug may be wet, smell of diesel, or look burned - this means you have an air leak. An acceptable solution is to spray out the socket with brake cleaner, and fill it to the lip with silicone RTV. When that cures, it will be an impenetrable permanent plug that should seal the air leak. As the system is under vacuum and not pressure, this could be where you are getting air in the system.
Now, about the plunger button: This WILL NOT STAY FIRM after you have run the engine. It is a one-way valve that shoves fuel into the line between the button and the high pressure fuel pump. Once that space is filled with fuel, the button gets firm. As soon as you start the engine, the pump sucks the fuel in, and reduces the pressure in that section back to zero / vacuum. This is normal and it is NOT an indication of air in the fuel.
geordi:
It is a dumb design only when used in a negative fuel pressure situation, like we have here with the CRD. Installing an in-tank fuel lift pump and subsequently plugging any leaks in the CRD fuel system cures the fire hazard problem. To label the O.E. fuel head/heater combination of the CRD as simply being a "Dumb design" is rather short-sighted on your part. Furthermore, posting that removing the electrical lead to the fuel heater, and then sealing off the electrical port connection with RTV silicone as a proper cure for the problem will likely cause unintended consequences, like a loss in efficiency and power production of the engine.
Do you feel that you can get away with this backyard "repair" because you live in a hot climate? What about all of us who live in cold climates? The next time you have an idea for one of your repairs, why don't you consult with a diesel technician or a diesel fuel systems engineer?
Preheating diesel fuel is desirable because it increases combustion efficiency, even in warmer climates. This is why the fuel heater is designed to be on all of the time; the diesel engineers who designed the R428 in the CRD determined that heating the fuel is necessary to squeeze more efficiency out of the engine. Most diesel powered vehicles - both passenger and commercial applications - have a diesel fuel heater somewhere in the fuel system to optimize fuel temperatures to maximize the atomization and combustion of the fuel when it is injected into the cylinder. Heating diesel fuel is not simply accomplished to prevent gelling of the diesel fuel in winter weather.
Your signature indicates that you are a "Proud supporting vendor of LOST Jeeps"... yet, when I check on the LOSTJEEPS.com Vendor's Alley, your status as an Official Vendor ended on September 7, 2016. Either have Heather properly update your status to indicate you are a current paid Vendor, or remove your claim to being a supporting Vendor from your signature.