The Care and Feeding of the Ford 7.3L Diesel
The 1999 to 2003 Ford 7.3L Powerstroke diesel engines are considered to be very desirable engines with operating lives routinely running to 500,000 miles and occasionally even to a million miles. That doesn't mean that there won't be problems with the "bolt-ons" like alternators and steering pumps, those fail just about as often as the same parts on gas engines.
The Ford 7.3L engine was built by International for Ford and the T444 International engine often found in the big schoolies uses the same short block. When used in a van based bus the big 7.3L really fills the engine compartment making many repairs a challenge. The lack of space forced Ford to delete the intake air intercooler and de-tune the engine as a result, so horsepower and fuel mileage ratings of the E-van engines are lower than the ratings of the same engine in the F series pickups.
Diesel maintenance is a lot like gas engine maintenance except that everything is "more." More oil, more coolant, more transmission fluid (but no ignition system). Capacities are double or triple what would be found in a comparable gas engine. Parts are generally more expensive, but on the plus side, Ford parts (and repairs) are easily available just about everywhere. There is no ignition system on a diesel engine but they can have fuel problems, especially in cold weather. The diesel is a great beast of an engine, but compared to a gas engine, tends to be a bit "needier."
- 15 quarts capacity. Use only diesel rated oils (I use Delvac 1300 Super 15w40). The Powerstroke engines use high pressure engine oil to fire the injectors and when the oil gets old it tends to foam which makes the injectors fire erratically. Many an engine problem has been fixed by simply changing the oil. I change mine at 3000 - 4000 mile intervals or once a year. The oil filter is a big one and holds a lot of oil which makes it a bit heavy when swapping filters, so when I change mine I poke a hole in the bottom with an ice pick and drain it first. Just make sure you can slightly unscrew the filter first. The oil filter has a larger diameter than the typical car oil filter and most filter wrenches won't fit.
18 quarts capacity Mercon V. The earlier years came with the E40D trans and later ones got the 4R100 trans. These are generally considered to be merely adequate transmissions. The vehicle manual says not to use Mercon V but Ford reformulated it in 2006 to be compatible with these transmissions. Check your fluid level with a warm, idling engine. Checking it cold can give false results. Note that there is a hot and cold mark on the dipstick. The later years came with a drain plug in the pan and the pan gasket is reusable. If you want to completely replace the trans fluid see "Ford E-450 ATF change instructions" below.
- 8 gallons capacity. These engines use either the old style green coolant or the newer diesel rated red coolant. If yours has the green stuff it will periodically need to be checked for SCA (Supplementary Coolant Additive) levels. See the Ford E-450 Coolant Flush
section below for more information
Brake fluid -
Dot 3 or 4.
Power steering pump -
Ford steering pumps use Mercon V automatic trans fluid, not "power steering fluid" that the parts stores sell.
- The E-van air filters live under the "Turbo diesel" plastic cover on the engine intake cowling. Just flip the spring clips and the cover should pop off easily. The cartridge filters (2) are a breeze to replace.
- Change every 15,000 miles. The fuel filter/water separator is in the fuel bowl which is mounted on the engine behind the plastic air filter assembly. To access it, remove the air filter assembly and find the round fuel bowl which is mounted at the front of the engine in the valley between the valve covers. Use a large oil filter wrench (same size that fits the engine oil filter) to unscrew the plastic cap to get at the filter. Some caps have a 1/2" socket cast into the top for a ratchet wrench. Space is tight in the E-van engine room and the fuel bowl top is very close to the van body. Some new fuel filters come with the plastic cap attached to the filter and I could not get this type filter into the bowl on my bus. I had to get a filter without the attached cap and re-use the old cap.
Remove the old filter and clean any junk out of the fuel bowl. I attached a small plastic tube to my shop vac and sucked fuel, water and sediment out. The new filter will come with two O-rings; one round and one tapered. Put the round O-ring in the groove at the bottom of the filter, lube it with some fresh fuel then push the filter into the bowl, O-ring down. The top of the filter will still be above the top of the fuel bowl. The only tricky part is installing the tapered O-ring. Slip it onto the cap with the taper toward the top of the cap. Many leaks have been caused by facing the taper toward the bowl. Snugly tighten the cap and you're done.
Fuel bowl water drain
- The water drain is a small lever (usually yellow) on the lower passenger side of the fuel bowl and likely pretty well buried by wiring and stuff. Some years have a pull cable attached to the lever that runs up to the cowl area. The "Water in Fuel" light on your dash will tell you when it's time to drain the fuel bowl. You open the valve for a few seconds and water/fuel/crud drains out of the fuel bowl, down the side of the engine and all over your driveway.
- There are two fuel strainers on the fuel pickup in the fuel tank. Some buses have an access hatch in the bus floor which makes getting at the pickup worlds easier. Otherwise, you have to cut a hatch yourself or drop the tank to get at it. Ford uses quick release fittings on the fuel lines and to disconnect them you need the special quick disconnect tools that fortunately are available cheaply at most auto shops. My strainers were pretty well plugged with 100,000 miles on the clock.
- The early Powerstroke 7.3L engines had an engine mounted, cam driven fuel pump while the later years have an electric pump mounted on the frame rail down below the driver's door. Easy way to tell which one you have is to turn the key to "accessory" and listen for the hum of the electric pump. The electric pump is nice because it's easier to replace and makes purging air out of the lines effortless. After doing fuel line work just turn the ignition key to "accessory" for a bit and the pump will refill the lines and fuel bowl.
Serpentine belt and idlers
- The serpentine belt powers the water pump, alternator, AC compressor, vacuum pump (which feeds the power brake booster) and power steering pump so keeping the belt and idler pulleys in good shape is essential. Two of us here have had an idler fail in the middle of nowhere and when that happens you ain't goin' nowhere. Both are relatively easy to replace but you'll first have to remove the air filter cowl.
To un-tension the belt, slip the drive end of a 1/2" breaker bar into the socket in the idler/tensioner body and pull like hell toward the passenger side. When the belt goes slack just slip it off one of the pulleys and ease off the breaker bar. If you're replacing the belt leave the old one in place to show you where to route the new belt. The idler assembly only costs $60 or so. I carry a new serpentine belt and a replacement pulley in my onboard spares.
- Diesel doesn't absorb water as well as gasoline does and water tends to fall out of the fuel in cold weather. This can cause algae to grow in the tank and cause rust in the tank itself. I throw in a container of Power Service's Clear Diesel (Walmart has it) once a year to keep the tank healthy. Keeping the fuel tank full also helps keep condensation from forming in the tank. Don't use alcohol based water absorbers in diesel engines.
In cold weather diesel fuel can gel, especially if your tank is full of summer blend fuel. Winter blend fuel is more tolerant to cold weather but in really cold weather may gel anyway. There are many additives that prevent gelling but it's best if they are added to the tank before cold weather hits so the entire fuel system is treated. Power Service's Diesel Fuel Supplement + Cetane Bost is a popular anti-gel additive.
- Our rigs tend to sit parked a lot so tires usually rot before they wear out. Look for small cracks in the casing which show that the rubber is drying out. The conventional wisdom among RV folk is to replace tires every 5-6 years regardless of tread wear.
- Most shuttle buses run 16" light truck rated tires that can be inflated to 80 lbs. but you don't have to inflate them to 80 lbs if you are lightly loaded. Have your bus weighed at a truck stop (weighing each axle separately) then consult the tire manufacturer's inflation specs for the proper inflation for your axle loads. Our bus is about 2000lbs. under max gross vehicle weight (GVW) so I can run 60 lbs inflation on both axles which gives us a much better ride.
I figure that with a dually rear axle I always have what amounts to two spare tires so I don't carry a dedicated spare. Our bus doesn't even have a mount for a spare. If we get a flat rear tire I'll just ride (slowly) on the good tire to the nearest repair shop. If we get a flat front tire I'll set down one or two of my 2x10 leveling boards and drive one of the inside rear dually tires up on it then pull the outer wheel. Then I'll jack up the front with my bottle jack and pull that wheel then swap the wheels and head to the repair shop with one flat rear tire.
Transmission mounted emergency brake
- The E-450 emergency brake unit is mounted to the tail of the transmission and has an oil reservoir which holds a small amount of Mercon automatic transmission fluid (4 ounces or so) that keeps the bearings lubed. There's a fill plug on the body of the brake unit (17mm socket if memory serves) so to check it you unscrew the plug and check that the ATF is up to the edge of the hole. These units are EXPENSIVE to replace (like $1200 plus labor) so checking them out once in a while is well worth the effort.
- Keep the connections clean and the cells topped off with distilled water. If the electrolyte levels drop below the top of the plates they can warp and short out the cells. When that happens all you can do is replace the battery. A coating of dielectric grease on the cable ends and terminals helps keep them corrosion free. When in storage, and particularly in winter storage keep the batteries charged to prevent them from freezing. Starting batteries like to be kept charged and if allowed to be fully discharged may not take a charge again.
- The engine nuts and bolts seem to be all metric. The drive line (at least on ours) is a mix of metric and inch sizes. There are also fair number of Torx bolts here and there. Ours had Torx bolts on the left front brakes and Allen bolts on the right side brakes. Go figure.
The fuel lines have the Ford quick disconnect couplings. They are easy to disconnect but you need special tools for the job. Fortunately the quick disconnect tools are available at any auto parts store relatively cheaply.
If you replace the power steering pump or the vacuum pump you'll need a special tool to remove and replace the drive pulleys that press on to the pump shaft. Many auto parts stores will loan the tool for free.
Crank Position Sensor (CPS)
- The early years had a problem with CPS failures which could cause the engine to die briefly (like turning off the key) then restart, die for a short time then restart or die and not restart at all. The CPS is located at the front of the engine above and to the passenger side of the harmonic balancer. To remove it you disconnect the wiring connector (press the locking latch to release), use a 10mm 6 point socket to remove the mounting bolt then pry it out with a screwdriver. Grease the new one then pop it in, bolt it down then reconnect the wiring. This is another "must have" in your spare parts kit.
Turbocharger pedestal oil leak
- The turbocharger pedestals on these engines often leak oil from the exhaust back pressure valve (EBPV) actuator. Oil will leak down the back of the engine and appear to be a rear main seal leak. To repair, remove the turbocharger, remove the pedestal and either rebuild the actuator or remove the actuator and valve altogether and seal the shaft holes in the pedestal. The EBPV closes in cold weather to make the engine warm up faster so if you're in a warm part of the country or don't use your bus much in cold weather deleting the EBPV is a cheap alternative.
Loose turbocharger housing bolts
- Some turbochargers have had the 4 turbine housing mounting bolts back out. When I removed my turbo to repair an oil leak in the pedestal the turbo literally fell in half in my hands! I found all 4 bolts laying in the engine valley. Incredibly, the turbo was fine (but I rebuilt it anyway). Replacement bolts with an interference thread for improved retention are available from Ford. The part number for the bolt kit is 1C3Z-9G486-AA. Basically, these "Improved" bolts are identical to the originals except that the threads in the middle threaded section of the bolts have been lightly damaged for an interference fit. It would be fairly easy to "modify" the original bolts with a light tap with a sharp cold chisel. Locktite won't work on these bolts due to the high temperatures involved.
Rebuilding the turbocharger is one of the easier jobs on an E-van. It's mounted at the back of the engine so removing the inside engine cover gives you easy access to it. Buy a rebuild kit online and make sure you have a 5/16" 12 point socket and a 10 pound sledge hammer handy (just kidding about the sledge hammer).
Glow plug relay failure
- The glow plugs help the engine start in cold weather so if the glow plug relay fails the engine may not start when the temperature falls. The relay lives on the passenger side valve cover and is fairly easy to replace. This is another candidate for the spares kit, especially if you operate in the cold a lot.
Under Valve Cover (UVC) wiring harness
- The UVC harness runs inside the valve covers and connects to the glow plugs and fuel injectors. It is known to sometimes degrade and cause engines to run rough or not start in cold weather.
Burning valves by lugging the engine on long hills
- The E-Van Powerstroke diesels are more than happy to pull up long hills in overdrive but this causes very high exhaust temperatures that can actually melt the exhaust valves and kill the engine. When on long hills I cancel overdrive by pressing the "overdrive" button on the end of the shift lever which makes the trans drop down a gear. The best way to go is to add an exhaust gas temperature gauge so you can keep an eye on the exhaust temperature.
Ford E-450 coolant flush
(This excellent article and the one that follows was sent to me so I can't give proper credit to the authors. Whoever wrote these - well done!)
You'll need the following:
*Tip* Do not use 50/50 pre-mixed coolant. After flushing, residual water will remain in your engine and cooling system that you can't get out. Therefore, adding pre-mixed 50/50 will further dilute the solution and yield a weak freeze point, along with a low level of corrosion and cavitation inhibitors. Your cooling system holds approximately 8 gallons. Adding 4 gallons of concentrate after flushing, and then topping off with distilled water, will ensure optimal protection.
- 4 gallons of anti-freeze concentrate.
*Tip* International who made your engine, and who's engine your Ford cooling system was designed around, recommended a Heavy Duty Extended Life Coolant (HD ELC) for all 2/2/99-up built engines (SN 940614-up). These are generally red coolants with operation lives of 300K-750K miles/6-8 years, depending on brand. They are very robust and require no maintenace or additives. Popular brands include International's Fleetrite ELC, Shell Rotella ELC, CAT ELC, Chevron Delo ELC, Peak Final Charge, Prestone Heavy Duty ELC, Zerex Extreme Heavy Duty, etc.
*Tip* Due to International's compatibility tests, all pre-2/2/99 build engines (pre-SN 940614) should use a conventional coolant with the addition of SCA (or a pre-charged conventional coolant already charged with SCA). Most conventional coolants will be green, "low-silicate" and meet ASTM D4985. There are too many brands to list. They will require the addition of a supplemental coolant additive (SCA) at initial fill and maintenance of that SCA thereafter. Most pre-charged conventional coolants will be pink, purple, or blue and meet ASTM D6210. These coolants do not require an initial dose of SCA, but will require SCA maintenance thereafter. These are coolants like Peak Fleet Charge, Prestone Heavy Duty, Zerex Precharge, Shell Diesel Ready, Fleetguard Fleetcool, Fleetrite Fully Formulated, and so on.
*Tip* Do not use "All Makes - All Models" coolants, or "Universal" coolants. They will not meet the needs of your diesel engine.
*Tip* Either a Nitrite only DCA-2 SCA or a Molybdate/Nitrite DCA-4 SCA will work.
- SCA (if using conventional non-charged coolant). Amount depends on the SCA maker (usually 3-4 pints).
*Tip* Tap water contains undesirable minerals, chemicals, and pH. If your tap water is good quality, you can do fewer distilled water flushes.
- Up to 20 gallons of distilled water
*Tip* The "T" regulates and restricts faucet flow. Directly connecting to your faucet without one of these "T's" could damage your cooling system.
- A Prestone flush kit with 5/8" "T". HERE is a photo of a NAPA #720-1286 5/8" flush kit with "T".
*Tip* Now might be a good time to consider replacing:
- 1-1/2 foot of 5/8" hose (to go on flush "T").
- A new thermostat gasket. OEM Part# F4TZ-8255-A
Thermostat (OEM Part #F6TZ-8575-EA)
Thermostat housing (OEM Part# F81Z-8592-AA)
Upper radiator hose that goes around serpentine belt (OEM Part# F81Z-8260-CA)
Lower Radiator hose (OEM Part# YC32-8286-CE)
Degas bottle cap (OEM Part# F6DZ-8100-A)
New coolant filter (if you've added one)
Any hose clamps that you feel should be replaced.
*Tip* A children's small plastic wading pool works good for a catch container. Some fit between the front wheels perfectly.
- 3/4" wrench for drain plug
- 8mm socket with rachet and extension for thermostat housing bolts
- 1/4" socket driver for block plugs
- Pliers for hose clamps
- Torque wrench to re-torque thermostat housing bolts
- Emery cloth to clean thermostat housing and hose connections
- Bucket and suitable catch containers.
(Continued next post)