More IP timing questions

[indestruktable]

Forgive me if I sound ignorant here; I have a fair bit of experience with gas engines but this is my first diesel and I want to make sure I do this properly. I'm replacing my timing belts and am now at the stage of setting the injection pump timing.

I have disconnected the cold start device.

I have the dial indicator and long stand for it, and they are threaded into the pump. I'm following the green book instructions, but per popular advice on here am not moving the pump on its bracket; I was planning on just setting the timing by moving the sprocket on the back of the engine.

The confusing part is, where exactly do I set the dial indicator to 0? The pump sprocket does not move smoothly as I expected, it's more notchy and seems to want to go to certain points but not others. I can't seem to get it to stop with the notches all lined up, which is, I think, where I should be setting the indicator to 0. I'm getting a little frustrated, because I know that if I don't do this right, the thing won't start or run well.

Am I correct in thinking that I can hold the sprocket so that all the notches are lined up, set my indicator to 0, and go from there? I have the VW lock tool which will not fit into the pump because the firewall is too close.

[indestruktable]

Edit/addition... I re-read the green book a bit more slowly and carefully, and went out and took a few pictures.

Someone please tell me if this is NOT "zero." Otherwise, I think I've got the gist of it. The greenbook seems to have a typo- it says to lock the IP gear with 5193, then turn the back sprocket to set the pump! That seems rather impossible.

[ATTACH=CONFIG]300[/ATTACH][ATTACH=CONFIG]301[/ATTACH]

[piper109]

Originally Posted by indestruktable

Edit/addition... I re-read the green book a bit more slowly and carefully, and went out and took a few pictures.

Someone please tell me if this is NOT "zero." Otherwise, I think I've got the gist of it. The greenbook seems to have a typo- it says to lock the IP gear with 5193, then turn the back sprocket to set the pump! That seems rather impossible.

[ATTACH=CONFIG]300[/ATTACH][ATTACH=CONFIG]301[/ATTACH]

You are right dont bother with the locking pin. It seems misleading.

First bring engine to as accurate TDC as possible.
Set dial indicator gauge with about 2 turns preload. You want to be sure the IP bottoms out before the gauge does.

Gripping the just loosened rear cam shaft sprocket with a tool in the spokes, wind it backwards until the dial gauge reading goes to its minimum. This is the "zero" you want.

Set the rim marker and the dial to that zero position.

Now turn the cam shaft sprocket forwards till you get about .9mm or the position you have chosen. Tignten up the sprocket center bolt a bit, enough to make sure it wont move but don't torque it.

Now using the crankshaft bolt turn the engine backwards a bit. It should go back to that same zero mark on the dial indicator.

Now turn the engine forwards again till you reach TDC. Read the gauge. This is how far your timing is advanced.

Make fine adjustments till you get the figure you want. You will find that you have to go a teeny bit higher than the value you want for it to come right.

Once you are happy with the position, torque up the rear bolt. I do this by reacting against the already tightened front camshaft bolt with a wrench but others prefer other ways.

Its quick and easy once you have grasped it.

Good luck,

Steve

[indestruktable]

Thanks, that helped. I watched a few more YouTube videos and it "clicked-" you're right, it is quick and easyonce you grasp the concepts involved.

I'm completely done with the job now. Set the timing to .97 or 98 because my cold start is broken, and I plan to run B20- I've heard it's advisable to increase timing slightly when running biodiesel.

Now all I have to do is reinstall the rad and fire it up! I can't wait, although I am a little nervous about the proper tension on the tbelt- I've seen v8volvo's videos and I think I'm close, just paranoid.

[indestruktable]

Finished up today. Unfortunately the battery was dead- once I charged it, it fired right up. Ran pretty bad with lots of clanging and hunting but that is, I assume, because I disconnected my broken cold start device. Tomorrow I'll tighten up the alternator belt - I turned the engine off because it was squealing- and test it further. But overall I'm inclined to say it seems successful. Thanks everyone!

[indestruktable]

I'm having some trouble getting the thing to start. I'm charging the battery now - I'll spare the details but I somehow switched my battery charger off last night and didn't get much of a charge on the battery.

But with the charge I did have, I got the engine to crank over after cycling the glowplugs, and it would run for a second- just a couple of revs, and then die.

My cold start device is disconnected because it's stuck, so I set the IP timing around .97.

I know that because I unscrewed the plug on the IP to set the timing, I'll have a bit more crank time, but just how much crank time is normal?

[indestruktable]

http://www.youtube.com/watch?v=hGNbQf33DXU


Here's what is going on with it. Before I was able to take the video, It ran for about 5-6 seconds and smoothed out to idle pretty well in that time, but now all I can get is this.

Note that the clicking/knocking noise after it stalls the second time was ME hitting the accelerator pedal, not anything with the car.

I can smell burnt diesel smell pretty bad in the garage whenever I try to do this, although I assume that's normal when you try to start a diesel engine.

The engine has 215,000 on it and was rebuilt around 115,000. It ran pretty much perfectly before I pulled into the garage for the belt job, except the cold start device was stuck so it is currently disconnected.

I set the IP timing to 0.97- maybe I did not do the IP timing correctly, but I'm pretty sure I did- aligned the notches on pump and pulley, set dial indicator to ~2mm, turned pulley back until indicator bottomed out, then turned clockwise to about .97 and tightened the rear sprocket down while counterholding with 5199 equivalent.

[v8volvo]

Hmm.

Sounds like either air still left in the lines, or timing far off. Usually even with timing quite far retarded it will still start readily, then sometimes stall a couple seconds later once the glow plugs switch off.

Did you rotate the engine at all with the injection pump belt removed, after timing the cam but before timing the pump? If you did, then you may have timed the IP 180 degrees off. This is possible even if you use the crank markings correctly -- you can time it to crank TDC #1 but cam #1 BDC, or in other words, instead of piston being at compression TDC, it's at exhaust TDC. Often in such situations the engine will briefly fire with residual fuel after a long crank time but then run poorly and quickly die as the residual fuel burns off, just as you are observing.

First step would be to make sure your fuel lines are primed -- you can quickly check that by loosening the 17mm fuel delivery pipe union nuts at the injectors and cranking the engine while watching to see when fuel comes spurting out. If you are already primed then you will see fuel immediately. If it takes a little bit of cranking before any comes running out, then you had a loss of prime and (hopefully) some cranking and bleeding will get it straightened out.

If that is not the source of your trouble, then my money is on timing. First start by taking the pump plug out and re-checking basic timing with the dial indicator again. You are sure you got the zeroing procedure right? I'm not familiar with your method -- it's not the one that I use. My method is to insert dial indicator before setting engine to TDC, then using a 27mm or 1-1/16" socket on the crank dampener bolt, rotate engine while watching dial indicator and go until the needle reaches its lowest point. Set your zero point there. Forget the 2mm setting. Then rotate by hand all the way around until you are approaching #1 TDC. (Your hint for this is by feeling/watching the back if the IP drive pulley, which has a notch in its rear flange. When the notch aligns with the marks at the outside of the IP and bracket, that is roughly #1 TDC, so as the pulley comes around and the notch nears that point, get ready to start watching through the bellhousing hole for the flywheel marks. Make sure you are reading the right flywheel mark as well -- it is not a notch, but a "0" marked into the flexplate, which can be tricky to see especially if there is a little surface rust on the flexplate rim.) As the notch approaches TDC, bring the flywheel slowly around until the 0 aligns with the pointer inside the bellhousing. Once it is there, look at the reading on the dial indicator. Anywhere in the neighborhood of .90-.98 will be a good reading. If you overshoot, you have to either back way, way off (greenbook says 1/4 turn but with an older, slightly sticky IP you need a lot more than that), or, as I do, just go all the way around again, 2 full crank rotations.

If your reading after measuring this way is off, then readjust static IP timing using method of loosening and turning rear cam pulley.

If your reading appears to be on after measuring this way, your next step is to set to #1 TDC and remove the vacuum pump from the cylinder head. This is the quick trick for figuring out whether the cam is at TDC or not without removing the valve cover. If the vacuum pump seems to be coming out under a lot of spring tension, even after you have wound its mounting nuts a significant way off, then you are timed 180 degrees off on the pump. If the vacuum pump is under slight spring tension as you first remove it but after loosening the nuts a bit, it sits loosely on its mounting studs, without tension from the drive rod pushing against it, then you were phased correctly. (The cam lobe that drives the vac pump is bottomed when the cam is at #1 TDC and at full height when the cam is 180 off #1 TDC -- a useful and clever move by the Audi engineers!)

If you find you are timed 180 off, you know what you have to do.

You'll get it figured out! If it ran well before, then guaranteed you will be able to make it run at least as well now, and probably even better. Likely it is something simple. At least you have the good updated Bosch SR97 starter. Someone must have replaced it in the past on your car. Sounds nice and healthy!

[indestruktable]

As usual, super helpful information- thanks!

I will try your method of setting the IP timing. I did not rotate the engine at all with the pump belt off, but I did turn the pump many times because I was confused about where the notches were and stuff like that.

I did have the plug removed from the injection pump for days, maybe even a week or more, while I was waiting on some parts. So I'll loosen the 17mm nuts as you mentioned - maybe it lost its prime.

As for the mark on the flywheel, I was indeed using the "0-" I can't believe I saw it but somehow I did.

Thanks for the help and encouragement, I'm sure I've asked some ridiculous questions as I'm totally new to diesel (and hooked). I'll be sure to post back as soon as I figure out what's going on. I'm actually not all that discouraged- at this point, I'm thinking I just messed up some adjustment and it'll work out.

[ngoma]

About the vacuum pump: Loosen the lower nut first/more than the top one, or else the spring tension may break the mounting ear off the vacuum pump. Also, don't let the rod slide out and roll around on the dirty floor. And put the rod back in the same way it came out-- i.e. the end riding on the cam should be the same end riding on the cam.