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Old 05-15-2022, 03:31 PM
Echo1975 Echo1975 is offline
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Join Date: Dec 2021
Location: Finland
Vehicle: Volvo 240
Posts: 33
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Quote:
Originally Posted by v8volvo View Post
I don't think that method is necessarily wrong. I think your pump timing setting process should give a successful reading, assuming you are using the method of loosening the four fasteners holding the pump to its brackets and rotating the pump in order to get the desired reading on the dial indicator. Correct?

When saying this is not the way to do it, ngoma meant that this is not the "best/easiest" way -- it's easier/better to do using the 9995199 counterhold tool and rotating the cam sprocket rather than moving the pump. However, correct timing can be achieved using your method as long as you understand how to do it. It's just more labor intensive and can sometimes leave the pump in a resting position that obstructs access to #5 and #6 injectors and glow plugs (although on the NA engines without as tall of an IP, this too is less of a factor).

So, bottom line, your methodology of adjusting timing should not prevent you from getting a successful setting, as long as you are able to tolerate the extra effort versus our preferred method.

But there are still things that could be causing a problem. You asked,



Not understanding this exactly. Why are you rotating counterclockwise (backwards from engine rotation)? I think it is true that if you go CCW, the reading would be falling as you pass through the zero mark and then not begin to rise again for several degrees. But you do the timing process in the CLOCKWISE direction, and in that direction the above is not true.

The way the timing *checking* process works is that you:
- disengage the cold start device so that it is resting in the hot position (sounds like you did this)
- install the dial indicator and its holder, then begin turning over the engine and adjusting the holder so that you achieve the correct ~2mm (at least 1mm) preload on the dial indicator AND have it zeroed successfully. it should return to the same zero point consistently each time the reading falls AND that zero point needs to be with preload so that you know it's zeroing on the low position of the pump plunger, NOT zeroing on the tool's own internal stop. Recognize that if you don't achieve these things then the dial indicator's readings are meaningless and could misinform you.
- then once you are sure you are set up correctly in terms of preload and zero point, continue to turn the engine over until the notch on the IP pulley begins to approach the marks on the pump case and bracket, indicating that your #1 cylinder's piston is on the approach to compression TDC
- when you see the dial indicator fall to zero one last time before #1 TDC, then start to climb again, now look into the bellhousing at the flywheel and slowly bring it up to the 0 mark. When it centers the 0 mark with the pointer in the bellhousing, look at the dial indicator. Whatever it says there is your correct timing reading.

NOTE that in this process, the dial indicator will begin to rise BEFORE the zero mark on the flywheel is reached. In fact the 0 mark on the flywheel is where you need to stop to take your reading, and by that point, the timing on the indicator should already be around 0.90-0.95mm.

If readings do not appear at the expected crank angles on the dial indicator, then to me, that means that your dial indicator may not have had enough preload set on it. It could also mean timing is grossly retarded but if it were that bad the engine probably wouldn't run.

Is that question I'm asking making sense? The setup and calibration of the dial indicator is a key step that is easy to overlook so may want to revisit that if you are not sure.

I still think the driveability (bucking and low power) you are mentioning could be improved with known correct timing. To be sure on cam timing you do need the locking tool. It is available on ebay very cheap for the VW application so worth getting one and getting it right. Easy to do with valve cover and rear cam gear removed. It does need to be correct. Eyeball is really not good enough -- again remember that, unlike say a TDI, this engine has no computer controls so it cannot compensate at all if things are not set up right.

The inconsistent RPM behavior does sound like air in the system but it could also be a light load misfire due to incorrect timing. Try timing first, once you are rock solid on being sure that's right, there would be other things to look at.

It will get there!
Yes, I loosened the bolts and rotated the pump. I got the pump timing right on the first couple of tries so I think I will stick to this way of doing it.

I looked at a tutorial where I am pretty sure the guy said counter clockwise on the crank until the number on the dial stops rising and then back and see if it shows the same amount.

Your way of doing it is way different so I will definitely check what the reading is with that.

Today I noticed the car has started to run better and the smoke was just a thin haze when hot now so something is going on and it's being improved over time.
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