DT 466 Diesel Engine Fuel Pressure Test

DT 466 Diesel Engine DT/DTI/DTA (C Engine) Fuel Pressure Test with a Robert Bosch 'MW' and 'A' Fuel  Injection Pump.

The primary reason for checking fuel pressure is a performance complaint which could be caused by low fuel pressure or restricted flow. This simple test will help determine firstly if the filters are plugged or if there isn't enough flow to the injection pump.

The fuel pressure test on a DT 466 Diesel Engine with the Robert Bosch injection Pump is a straight forward procedure that requires a fuel pressure guage that reads up to 160 psi connected to the vent plug located on top of the secondary fuel filter housing. 

DT 466 Diesel Engine Fuel Pressure Testing Procedure

The fuel pressure has to be a minimum of 20 psi at engine high idle (no load). High idle is full throttle (linkage contacting high idle stop), transmission  in neutral.

If the pressure is low... replace the fuel filters. Retest fuel pressure and if the readings have not improved the next step is checking the 'transfer pump inlet restriction' (coming up in my next post).

The DT 466 is a mechanical injected fuel system and as you can see troubleshooting is pretty straight forward. No laptops required :)

The first reaction to low power complaints is to replace the fuel filters and most of the time that will be the cure. It's also interesting to see how much of a difference the filters make before replacement. 
The next post will be all about testing the DT466 for 'transfer pump inlet restriction'


Comments Welcome!

MaxxForce DT Diesel Engine

This video is on the big Bore Models in Highway Trucks and covers a large part on how the MaxxForce Engines are contructed.

The MaxxForce DT Diesel Engine is the newest edition of the original DT 466 and DT 466E diesel engines. Our fleet brought in five 2010 IC conventional school buses with this engine model. They are 230 HP with a 7.6 Liter (466 cu. in.) displacement.

They stuck with the wet sleeve cylinder design which is very popular with us Mechanics who do in-frames. If you've ever done an in-frame there is no comparison to an integral (DRY) cylinder diesel engine model. The dry sleeve design of course means pulling the entire engine out of the frame. This adds labor and parts expenses.

I did some research on these diesel engine models since it's always an advantage to know the details on our fleet engines. They have the roller cam followers which helps reduce wear and tear on the camshaft and valve train. A 4 valve per cylinder configuration helps with breathing and emission controls.

This video explains the EGR system in Maxxforce 2010 Engine Models.

Other features include:

• replaceable valve seats and guides
• top of engine access to fuel filter and fuel/water seperator
• top loading fuel strainer
• maintenance free closed crankcase ventilation system
• internal cylinder dosing eliminates downstream fuel injection equipment.
• On-board diagnostics system
• International's electro-hydraulic generation two (G2) electronic controls for optimizing fuel economy and delivery. 
• G2 fuel system allows diesel particulate regeneration without equipment dowstream.
• EVRT electronically controlled turbo creates improved engine torque curve and response and produces exhaust back pressure to better control EGR rate of flow and exhaust braking.

Jacobs exhaust brake (optional) up to 150 brake horse power. Works with the EVRT Turbo eliminating standard exhaust brake system.  The MaxxForce DT Diesel Engines in our fleet have been running great so far.