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4bd2t checking and setting timing

16K views 14 replies 6 participants last post by  Kowalski  
#1 ·
Set the motor on TDC with the auto timer lines lining up.

Turn the motor over (normal rotation/direction?) Until fuel comes to the top of the delivery valve holder (delivery valve spring removed).

Is it when fuel reaches the top of the delivery valve holder or comes out the whole?

Setting:
Where are the four automatic timer bolts located? Two right next to the lifter pump, two on the front side? Remove the radiator support bracket?

My manual is limited and I'm lost on this.

Thanks
 
#2 ·
Sorry don't have much info on this, but I have heard you can't go with those marks on the harmonic balance all the time, because sometimes they will rotate on themselves and be off couple degrees. Since it is suspended by rubber.
 
#4 ·
I think on the right side (opposite side of injection pump) there is a cover with two bolts 10mm right about the "T" on the front cover. Under that cover it has a pointer that points to the cam gear that has a mark on it. But I don't know if when those line up if its at TDC.

Do you have a service manual handy?
 
#5 ·
Yes have the service manual. Removed the cover and lined up the mark, and its landing on TDC on the balancer. As well, the appropriate valves are loose at TDC. About 25° before that is when fuel comes out. Its supposed to push fuel out at 8°. So I guess I need to time it. Still not sure where I call it on fuel coming out, its about a 0.7mm difference.

I bought it for dirt cheap but it was heavily neglected. 300,000 miles. Water seperator/tank filled with brown "goo". Suprisingly it ran.

I'm looking for an app to take a screen shot of these mounting
 
#6 ·
Hopefully you can take the injection pump out rotate it to proper tooth setting and be good to go. But if its still off after you do that. Then someone may have removed the injection pump then the gear from the injection pump and didn't have it clocked properly when it went back on. I think I read somewhere that the IP gear is on a tapper shaft that does not have a wood drift key to locate it and if you remove the gear it would need to be fixed at a diesel shop that has a IP dyno. Which wouldn't be bad with that many miles on it to have it checked out for proper flow and timing, and what ever maint. could be done.

Are you planning on using this engine to repower something? Or keeping it in the NPR?
 
#7 ·
For now, staying in the npr. In a few months, buy new npr, slide insulated box on, rip out motor, go shopping for the funnest project of my life. Want a 30's-end of 50's cabover or bread truck.

Supposedly, you loosen the auto timer mounting bolts, set at 8°, rotate pump until fuel stops coming out 1 delivery valve holder (see attached item 24). I just cant figure out which bolts they are.

Cleaned the fuel system (exstensively), valve adjustment, set timing, check compression, clean/bench check injectors, see if the power loss problem is fixed. Im hoping to avoid pulling the IP now, compression is ok but not great, want to resleeve, rebuild IP, and new turbo (same as compression). I have about two more months to sales on the farm shut down for a few months, have to time to shop for a new one.
 
#12 ·
Sorry, old thread, but this is a sticky...

If you remove the 4 nuts, you can remove the pump, if you have the gear off, which requires removing the front timing cover. If you want to remove the pump with the gear, the housing that the 4 nuts are fastening the pump to needs to be removed. 6 long M8 bolts through the front cover, and 1 short one on the back at the bottom (makes mounting the pump easier?)

The image is quite accurate in its representation.
 
#13 ·
Four studs with nuts attach the fuel injection pump to a mounting plate, which in turn bolts to the rear of the timing gear case.

The 4 studs pass through slotted holes in the front flange on the injection pump housing. The slotted holes allow the injection pump housing to be rotated (loosen the 4 nuts first) to adjust the timing. Rotating the injection pump in the same direction that the crankshaft rotates will retard the timing, opposite direction to advance timing.

The instructions for the spill timing method, might seem counter intuitive, because you rotate the injection pump housing until flow from the delivery valve stops. What is happening is:

When the pump plunger is at the bottom of its stroke the inlet port (in the side of the plunger barrel) is uncovered by the top of the plunger.
Now if you operate the priming pump, fuel flows through the inlet port into the plunger barrel, fills the volume above the plunger and starts flowing out of the delivery valve, because the spring and poppet were previously removed.

While still operating the primer pump, rotate the injection pump housing until the plunger rises and closes the inlet port. During the spill timing procedure, when the inlet port is closed by the rising plunger fuel cant flow from the priming pump to the delivery valve.

During normal operation, with the spring and poppet fitted back in the delivery valve, when the plunger is at the bottom of its stroke, the feed/lift pump delivers fuel through the inlet port to fill the plunger barrel, but the pressure developed by the feed/lift pump is less than required to push open the delivery valve poppet.

As the plunger rises, the fuel pressure is that created by the feed/lift pump, until the plunger closes off the inlet port. Then the pressure rises rapidly and the fuel can be injected. The crank angle when the inlet port closes is the timing for start of injection. Combustion starts after a short delay.