DT466E Injectors, Valve adjustment, and filter housing complete. 2

BobWolf

Veteran Expediter
Owner/Operator
21. If you plan to reuse the old internal injector wire harness clean it and check each wire for continuity on the terminals from injector plug to connector that passes through the valve cover. If it doesn’t zero out or shows any resistance replace it. Make sure you move the wires and connectors to make sure you don’t have a hidden break in the wires.
NOTE The “new style” is actually a comeback from the 1994 1999 injector harness Alliant power 634364 available at AP distributors. In late 2009 Navistar converted to the metal rail due to breakage of the plastic clips this part also covers the HT 530 and engines. Oil deflectors are also integrated into this design and eliminates breakage the need to remove the harness assembly when servicing the injectors.
Dealer cost around $350.00 - $400.00 D/W Diesel 250.00 What’s the difference between them you ask? The box.
Alliant makes them for everyone. The metal wire holder and oil deflector assembly attach with class 12.9 M6- 1”x16 Allen head cap screws. These are metric threads and can be found at any hardware or auto parts store. Cross up Hillman # 880329 make sure you get the metric black oxide.

The updated harness bolts run into the threaded hole in injector hold down plate. They just need to be reasonably tight.

Valve Timing.

OK, First a quick basic understanding of how an engine works, and what and why valve adjustment are needed.
All cars and trucks have a 4 stroke engine. 1 Intake, 2 Compression 3 Power 4 Exhaust.

T.D.C. Top Dead Center the highest the piston will travel in the cylinder bore. There are 2 TDC positions end of compression starting power stroke, and end of exhaust stroke starting intake.

B.D.C. Bottom Dead Center the lowest the piston will travel in the cylinder bore. There are 2 BDC positions 1 at the end of the intake starting the compression and end of the power stroke, and starting the exhaust stroke

Intake stroke. The intake valve opens the piston travels down into the block drawing in air and fuel mixture in a gasoline engine. In a newer diesel this should be only air. The piston reaches BDC intake valve closes completing the intake stroke both intake and exhaust valves are closed.
Compression. The piston moves up to the head compressing the air fuel mixture, this results in heat and high pressure.
Both valves still closed.
Power. At TDC compression a gasoline engine uses a spark to ignite the air fuel mixture a diesel dose not compression values are high enough to spontaneously combust. The air fuel mixture ignites forcing the piston down into the block.
Both valves still closed.
Exhaust. the piston again moves upward, the exhaust valve opens and exhaust is expelled. When the piston reaches TDC the process begins again starting with Intake.

Yes the actual timing of valve and ignition in real world differs slightly and nothing would happen without a crank shaft and cam shaft but I’m trying to keep it simple. Try and do keep it simple are two different things.

Now, the valve springs do two main jobs. They keep the valves in the head and seal the valves to the seats maintaining compression. Too much gaping at the rocker you starve and/ or suffocate the engine valves too tight results in power loss, poor mileage. Too little gapping you risk, cam shaft, lifter wear and possibly deforming the valves also a collision between the valve and piston. Any out of spec valve lash or premature valve, keeper, and spring wear, and failure and the engine swallowing the valve. THIS RESULTS IN A CHERNOBYL SITUATION FOR YOUR ENGINE Piston collision and swallowing a valve will destroy the engine. Please consider this as a warning Any questions of skill take this to a shop..

Valve lash on the DT 466 and DT 466E is .025” twenty five thousandths of an inch both intake and exhaust.
Torque on the jam nut is 20 Foot LBS. preferably with the engine cold but that's not overly crucial.
PAY ATTENTION check your adjustments and work after you make adjustments one cylinder at a time. Also turn the engine over by hand at least three complete cycles 6 revolutions. You should hear air escape each piston at least three times.
Look, listen and feel for binding or difficulty turning. If you start the engine and a valve is not adjusted is done incorrectly you will destroy your engine.

Valve adjustment is easier to do with the injectors removed as its easier to tell when the piston is at T.D.C. You can use the bolt on the crank pulley to turn over the engine. I was able to turn the engine by the alternator pulley as the injectors were out.
You can bring each cylinder to TDC compression and adjust each cylinder one at a time or use the following procedure.
You will be at TDC compression when the piston is at its highest point and both rocker arms have slack. Both valves will be closed.

1. Rotate engine until TDC [top dead center] is achieved. There is a notch on the serpentine belt pulley behind the vibration dampner.
An arrow and the letters TDC has been cast right into the front cover. Once lined up, the engine valves will be on #1 TDC compression or exhaust stroke.
An easy way to tell is if #1 cylinder valves are both loose and #6 cylinder valves have no clearance, then you know you are on #1 compression stroke.
Note: There are 12 valves in total #1 valve being at the front while #12 valve is the last valve at the rear of of the cylinder head.
So if I say adjust #4 valve you just count from the front of the head, the first valve being #1. This makes it easier to explain which valves to adjust.

2. At each cylinder use a 13mm or 1/2“ wrench six point preferred and a flat head screw driver loosen the jam nut apx 1/8 to ½ turn while holding the set screw give the set screw a small twist to check for movement, it should move easy but not sloppy.

3. Turn the set screw to adjust the lash to .025” using a feeler gage.

4. On #1 TDC compression stroke adjust adjust valves #1 #2 #3 #6 #7 #10 . .

5.Rotate engine 360 degrees the engine is now on #6 TDC compression stroke. Adjust #4 #5 #8 #9 #11 #12 valves.

6. While holding the set screw snug down the jam nut with a box end wrench not too tight, just enough so you don’t feel any drag on the set screw. You might need to take a couple cracks at snugging the jam nut as it can throw off the setting. I found before snugging down the jam nuts back out the set screw apx 1/8 turn your setting should be within a couple thousandths of being if not dead on. A couple thousandths 0.002 will not damage or affect the engine performance as long as your lash is adjustments are within specs. And consistent.

It might take a couple cylinders to get “the feel” to snug the jam nuts so take your time.
 

droberts

New Recruit
Owner/Operator
Hello,

I was wondering if your still around to answer some questions. We have a 1998 International School Bus and we torqued the head down but one of our rocker arm valves are in a bind. How do we correct this issue?
 
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