timing belt change injector pump witness mark help?

CobraDreaming · **Joined:** Tue Aug 23, 2011 9:24 pm **Posts:** 20

OK. I have the cam tools in place. The flywheel pin is in. The crank hub mark is at 3. The 4 bolt holes are at 12, 3, 6, and 9 but I don't seem to see the injector pump witness mark. I believe I have read here it really doesn't matter as it is just pressurizing the rail??

It would seem to me if nothing moves and I slap on the belt everything is still in time. Am I missing anything here?

4x4kingx889 · **Joined:** Sun Jul 17, 2011 6:42 pm **Posts:** 235

You need to have the injection pump in time that's what makes it fire the injectors when needed the only thing that doesn't have to be in time is the water pump

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mark2m · **Posted:** Wed Apr 24, 2013 8:08 pm

While it is called a fuel injection pump it has nothing to do with fuel timing. Basically all it is, is a high pressure fuel pump. The computer via the fuel injectors controls injection timing. I know there is a witness mark on it but I really don't think it makes much of a difference where it is set to. I've heard that the pressure pulses are suppose to be in time with the opening of the injectors but really. The injectors are activate in milliseconds and the pulse width, timing and amount of times the injector opens per stroke is all controlled by the ECM. The fuel rail stores fuel for the injectors at a high pressure and I believe it has more to do with helping with the pressure pulses.

My injection pump wasn't in time when I removed my timing belt. I had all three pins in also. No issue during reassembly. I think it was 180* out of time, I didn't see any marks on my crank. I must of missed it but anyhow, I pulled my head to replace my head gasket and all the pistons where sitting dead even in their bores. I can't see how anything would be damaged during assembly.

QCCRD · **Joined:** Tue May 08, 2012 6:02 pm **Posts:** 11

Doesnt the injection pump just pump to the "common rail" and the injectors take care of the rest?

Valve Stem · **Posted:** Wed Apr 24, 2013 11:16 pm

QCCRD wrote:

Doesnt the injection pump just pump to the "common rail" and the injectors take care of the rest?

yes

if you look at this pic you have to injection pump timing marks one at 10 and one at 2 their round circles

you can see it bigger here at http://www.flickr.com/photos/95139636@N08/8663610848/sizes/l/in/photostream/

Mine was set at the 2 o'clock position so that where I put it back together at

dragand021 · **Joined:** Mon Mar 11, 2013 11:52 pm **Posts:** 34

You should time it, it is important, plus it's easy to do. Look for it on the bottom of the gear, it is there. Once you have it timed, you will need to turn 3 full turns of the crank, before it lines up again, that is how you check if you have it timed correctly. Use the locking pins on cams an on the flywheel.

CATCRD · **Posted:** Thu Apr 25, 2013 12:03 am

This has been gone over multiple times. Correct timing makes a small improvement because of the pressure waves created by the 3 piston pump.

BlackLibertyCRD · **Posted:** Thu Apr 25, 2013 3:14 am

CATCRD wrote:

This has been gone over multiple times. Correct timing makes a small improvement because of the pressure waves created by the 3 piston pump.

DOC4444 · **Posted:** Thu Apr 25, 2013 6:13 am

I just did mine. The injection pump pulley appeared to be out of time when I took it apart. I put it back together that way. Did not run very well. Keith told me he ALWAYS resets to factory marks. I took it back apart and reset as per his instructions. Ran better than it ever has. (I assume it came that way from the factory.) No signs of anyone being in there before me.

I would suggest removing the tensioner and retiming the pump. I think it is worth the extra trouble. (The block mark is just under the small bolt in your picture.)

DOC

papaindigo · **Posted:** Thu Apr 25, 2013 7:57 am

I won't offer an opinion on fuel pump timing; that's been discussed a lot and I'm not convinced of the correct answer one way or the other. What I can say is the fuel pump pulley has a small notch that lines up with a small bump, mentioned in the string, BUT only on like every 3rd revolution. Hence, unless you make a special effort to get the engine to the point where the fuel pump marks line up it's perfectly possible to insert the cam pins and the flywheel pin with the fuel pump marks not lined up. IMHO this is harmless if you simply mark a fuel pump pulley tooth and the adjacent housing so the new TB can be installed with the fuel pump pulley in the original position. FYI that pulley spins quite easily so it may take a bit of fiddling to keep the marks lined up during the new TB install but if you do the fuel pump will be "timed" just like it came from the factory for whatever that's worth.

DOC4444 · **Posted:** Thu Apr 25, 2013 8:43 am

Except, I am convinced mine came from the "factory" with the IP pulley marks NOT in the "factory" position. Others seem to have found something similar. And, it clearly ran much better on initial startup and since. Since Keith STRONGLY suggested the "factory" settings, I think it is probably the best bet.

DOC

kjjet · **Posted:** Thu Apr 25, 2013 8:45 am

I was corrected a few months back. YES...the pump timing dose make a difference. This is what i was told:

Pump has 3 plungers and these events are timed to occur when the injectors are not firing. This is due to the pressure wave propagation in the fuel rail. Improper timing can lead to high or low fueling when an injector fires, depending on how the pressure wave lines up.

FYI...Time the engine per the manual like this:

Jeep Liberty CRD Timing Belt Replacement
Procedure (2.8l diesel)
Revised by KJJET
1. Remove cooling fan and shroud. *In order to remove them there is two methods.
A. Remove the grill, bumper, inner grill and electric fan. Then remove the bolts holding the intercooler and radiator. Now with the intercooler and radiator pulled back the fan and shroud can be accessed. Remove the shroud intercooler and radiator then move on to removing the fan.
OR B. Remove the grill and gain access to the intercooler and radiator bolts and remove them. This will give you a inch or two to access the shroud and fan.
The fan assembly is best removed with a very large crescent wrench on the nut just behind the fan viscous coupling. Then hit the wrench in a counter
clockwise direction with a small sledgehammer. It may help to
spray with penetrating oil. Worst case, wedge something behind
the fan drive pulley to keep it from rotating and then use the
sledge method.
2. Remove accessory drive belt.
3. Remove both idler pulley (right hand thread, 16 mm) (a), power
steering pump (3 bolts that you get to by rotating the pulley, 10
mm) (b), accessory belt tensioner (c), cooling fan pulley and
bracket( 4-13 mm bolts) (d), crankshaft pulley/damper (4-10mm
bolts, you may need to hold the pulley by the 21 mm center bolt)
(e), and alternator (2-13 mm bolts on the front and 1-15 mm on
the back side-note you will have to loosen the 2-13 mm bolts for
the bracket that holds the alternator to the cylinder head) (f) .
4. Remove the front timing cover (7mm bolt x 17)
5. Remove both plugs in the camshaft cover (one on intake side
behind alternator placement, one on exhaust side behind
thermostat area). Remove the plugs with a 5mm hex.
6. Rotate the engine clockwise only with a 21mm socket on the
front of the crankshaft until the crank timing mark is located at 90 degrees (3:00) and a 6mm hex key engages the hole in the flexplate/flywheel.
7. Inspect the two openings in the camshaft cover to see if the holes
in the camshafts align. If so, install the two pins into the
respective camshaft. If not, remove the 6mm hex key and rotate the engine 360 degrees at the crankshaft and re-inspect. Note: this may take up to 3 rotations to get all three installed.
8. Loosen the timing belt tensioner and rotate it counterclockwise by
hand until slack is sufficient to remove the belt from the pulley.
Remove the old timing belt.
9. With a sprocket holding tool, Loosen both camshaft sprokets by rotating the bolt (17mm) counterclockwise. It is sufficient to have them loose; they do not need to be removed.
10. Install new idler pulleys: remove them by turning clockwise to loosen then counter clockwise to tighten. Tighten to 53N-m or 39 Ft Lbs. Loosely install a new belt tensioner.
11. Ensure that the high-pressure fuel pump pulley is oriented
Properly (see picture) and fit the new belt to the crankshaft pulley. Install a small vise grip at the crankshaft to hold the belt in place while installing the belt counter clockwise starting with the fuel pump, idler pulley, cam shaft sprockets, idler pulley, water pump and lastly over the newly installed timing belt tensioner.
12. With the new belt properly installed, tension the
timing belt with the tensioner as shown in the picture. If the proper
handle isn’t available, the tensioner can be moved with two 3mm hex
keys. Rotate the tensioner until the proper gap on the pulley is
achieved. Tighten the center fixing bolt to 30N-m or 22 Ft Lbs
13. With a sprocket holding tool, tighten both camshaft sprokets to 108N-m or 80 Ft-Lbs.
13. Check tensioner and reset proper tension as needed.
13. Remove the two camshaft pins and crankshaft hex key. Rotate the
Clockwise only 21mm socket wrench, 720 degrees, re-check the tensioner and reset proper tension as needed.
14. Reinstall the timing belt cover.
15. As needed install new accessory belt tensioner, idler pulleys and reinstall everything in steps 1 thru 3.

If you want the pic's MP me.

Good luck!

msilbernagel · **Posted:** Sat Apr 27, 2013 12:59 am

Perhaps you can see the marks a little clearer here: https://www.facebook.com/photo.php?fbid=10200998493706846&l=4293cc96e3

The mark on the rear timing belt cover can be seen as the horizontal line immediately to the left of the yellow arrow and below the black circular thing at 9 o'clock left of the pulley.

The notch in the rear rim of the CP3's timing belt pulley is immediately to the right of the yellow arrow.

Line 'em up! :rockon:

Mark

BlackLibertyCRD · **Posted:** Sat Apr 27, 2013 1:33 am

How about the circle at about 11:00 o'clock? I put a customers CRD there and it ran great. I put my CRD at 6 o'clock and it also runs great. Soooooooooooooooo

timing belt change injector pump witness mark help?

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