Simplified Setting of PD Injector Lash

Franko6

Vendor , w/Business number
Joined
May 7, 2005
Location
Sw Missouri
TDI
Jetta, 99, Silver`
The Bentley book gives a complicated and problematic method for setting the PD injector clearances. The method is to use a dial indicator mounted onto the rocker, then rotate the engine until the full depth of the stroke is reached. Screw in the adjustor screw until it bottoms out. Then back it out 180 degrees. Tighten the ball screw lock nut to 24 ft lbs. VW did standardize the setting for all PD motors for a 180 degree setting.

The problem is, there is no decent place to attach a dial indicator's bolt-on or magnetic mount.

The following pictures show how to do the operation with no dial indicator.

this is the position of the cam with the #4 injector rocker fully depressed, side and top view:



The injector is pressed to full depth when the top of the INTAKE valve cam lobe is aligned with the center of the injector lobe roller. Note that for each cylinder, the intake lobes are located across the head e-i-e-i-i-e-i-e (i=intake, e=exhaust)

This makes adjusting the injectors a very simple 'eyeball' method.
 
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PDJetta

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Nov 6, 2003
Location
Northern Virginia
TDI
'04 Jetta GLS TDI Pumpe Duce Platinum Grey w/ Leather
Thanks Frank! I like that. Nice and easy.

Bentley shows a special VW tool that bolts onto the cylinder head using a valve cover bolt hole to hold the dial indicator and I was hoping a universal dial indicator holder would do, but I have no idea on how to attach it.

--Nate
 

jdennison

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Joined
Jun 4, 2010
Location
WV
TDI
2004 JETTA TDI PD
Frank I was wondering if you could send me those pics, I'm unable to enlarge them the site say I must register
 
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jdennison

Well-known member
Joined
Jun 4, 2010
Location
WV
TDI
2004 JETTA TDI PD
Thanks turbocharger I see how to do it now, thanks also Frank nice pics
 

Farfromovin

Torque Addict
Joined
Apr 9, 2005
Location
Ventura, CA
TDI
03 Golf 2dr- PD150 6m
Yeah, I got a real kick out of the Bentley procedure. Dial indicator lol. That thing is at a low spot for so long a 5yr old could set the cam correctly!
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
Any ideas on how much of resistance there should be when turning the adjusting screw clockwise, before the backing off? I mean, how tight should it be? How do I know it's enough?
 

Franko6

Vendor , w/Business number
Joined
May 7, 2005
Location
Sw Missouri
TDI
Jetta, 99, Silver`
I've seen guys over-tighten the ball screw. Loosen the set nut and turn the ball screw until you feel a change in resistance. Don't force it. Then back the screw off 180 degrees. Lock the set nut to 24 ft lbs.
 

rick.johnson0330

New member
Joined
Jan 29, 2012
Location
manchester
TDI
golf gt tdi
tdi 130 injector adjustment

can i ask how often should this adjustment on the injectors be done, my golf has done 120k as far as i know its never been done
thanks
 

apples12

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Joined
Feb 1, 2011
Location
Birmingham, United Kingdom
TDI
Mk5 1.9tdi Match, BMW F10 520D
Apologies for thread revival...

i'm going to be doing this procedure on my mk5 as it wasnt done when we changed the injectors 22,000 miles ago and i'm trying to eliminate things for my current 'best' of 43mpg (UK) motorway mileage....

am i correct in understanding the procedure is as follows:

1) remove rocker cover

2) Rotate CAM using 18mm spanner until the rear of the roller of the rocker arm is at its highest point... (thus compressing the injector the most)

3) screw the adjusting screw in all the way in until resistance is felt

4) turn the adjusting screw BACK 180 degrees

5) maintain position of adjusting screw and tighten the lock nut

6) repeat the procedure 1-5 with the other 3 injectors

i'm guessing the use of the dial gauge in the bentley manual/vw workshop manual is to ensure the rocker follower is at its highest point and the injector is compressed the most?

many thanks for any help
 

Nutsnbolts

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Joined
Nov 1, 2001
Location
Weare, NH
TDI
2000 Jetta, Silver Arrow
Franko6: Great post!

If anyone feels better about using a dial indicator for this procedure, I have a method that doesn't require the factory tool. I put the magnet mount on the injector rocker, which is steel, and it holds itself there securely and without any wobble. I then put the tip of the indicator on the cylinder head, on the machined surface between each cylinder bank, and rotate the engine until the indicator stops. Then set the injector lash. Works every time...

-Rich
 

oldpoopie

Vendor
Joined
May 14, 2001
Location
Portland Oregon
TDI
2001 golf gl, 2006 jetta, 1981 ALH swapped rabbit pickup, 1998 beetle
Apologies for thread revival...
i'm going to be doing this procedure on my mk5 as it wasnt done when we changed the injectors 22,000 miles ago and i'm trying to eliminate things for my current 'best' of 43mpg (UK) motorway mileage....
am i correct in understanding the procedure is as follows:
1) remove rocker cover
2) Rotate CAM using 18mm spanner until the rear of the roller of the rocker arm is at its highest point... (thus compressing the injector the most)
3) screw the adjusting screw in all the way in until resistance is felt
4) turn the adjusting screw BACK 180 degrees
5) maintain position of adjusting screw and tighten the lock nut
6) repeat the procedure 1-5 with the other 3 injectors
i'm guessing the use of the dial gauge in the bentley manual/vw workshop manual is to ensure the rocker follower is at its highest point and the injector is compressed the most?
many thanks for any help
Yes, but rotate the engine clockwise only, and only by turning the engine at the crank bolt. Its a 19mm socket and a big ratchet. Remove glow plugs for easier turning.
 

apples12

Veteran Member
Joined
Feb 1, 2011
Location
Birmingham, United Kingdom
TDI
Mk5 1.9tdi Match, BMW F10 520D
Hi,
many thanks for the reply oldpoopie

the last time we fitted the glowplugs i remember it was quite a 'challenge' to remove and fit them... and this was done at the mechanics...am i ok to complete the procedure with them installed? (my understanding is it would just make the turning of the cam difficult as the cylinder would be under compression?) would rather use a bit of elbow grease than risk stripping my glowplug threads!

thank you!
 

oldpoopie

Vendor
Joined
May 14, 2001
Location
Portland Oregon
TDI
2001 golf gl, 2006 jetta, 1981 ALH swapped rabbit pickup, 1998 beetle
Leave the glowplugs in then. You'll be fine, just need a big ratchet to push past compression.
 

jimbote

Certified Volkswagen Nut
Joined
Jul 10, 2006
Location
spiral arm, milky way (aka central NC)
TDI
Tacoma 4x4 converted to TDI
as stated above turning the engine over via the cam or any other method other than the crankshaft is a big no no!!....puts way too much stress on the cam belt @ the crank sprocket...it was just not designed for that kind of force.... that being said a method I use quite a bit to turn the engine over (most of the time on cam inspections with manual cars) is to put the car in 3rd or 4th and pull the car toward me while watching the cam... this is easier than wrenching on the crank bolt and much safer than using the cam....
 

Franko6

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Joined
May 7, 2005
Location
Sw Missouri
TDI
Jetta, 99, Silver`
Actually, for those who feel that using the cam to use as a rotating device, when we are replacing the cam, we ALWAYS turn the cam in order to set the ball screws. It is very fast and accurate. Of course, this is ONLY when the timing belt is disconnected.

As our procedure goes:
1) Bring the engine to TDC and remove the timing belt.
2) Replace the cam sprocket onto the cam pulley
3) Rotate the CRANKSHAFT backward 90 degrees (1/4 turn)
Now you can rotate the camshaft freely without any valve striking a piston.
4) Rotate the cam clockwise. As each rocker pushes the injector down (Firing order is 1-3-4-2), adjust the ball screw.
Just to be sure you aren't over-tightening a ball screw, first make sure that the ball screw is loosened a couple of turns. When turning the ball screw against the ball pin, you will feel the resistance of the injector spring for several turns. When the injector bottoms out, you will feel additional resistance. Then turn the ball screw in the reverse direction 180 degrees.
5) Return camshaft to a position that both intake and exhaust valves for cylinder 1 are 'UP'. That is Camshaft Cylinder #1 TDC.
6) Turn crankshaft to the position that the crankshaft lock may be installed. That is Crankshaft #1 TDC.
7) Follow balance of PD timing belt installation procedure.
 

audiphile

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Apr 20, 2008
Location
Irvington, NJ
TDI
shop full of swaps
This is exactly what we do. saves lots of time.

Actually, for those who feel that using the cam to use as a rotating device, when we are replacing the cam, we ALWAYS turn the cam in order to set the ball screws. It is very fast and accurate. Of course, this is ONLY when the timing belt is disconnected.

As our procedure goes:
1) Bring the engine to TDC and remove the timing belt.
2) Replace the cam sprocket onto the cam pulley
3) Rotate the CRANKSHAFT backward 90 degrees (1/4 turn)
Now you can rotate the camshaft freely without any valve striking a piston.
4) Rotate the cam clockwise. As each rocker pushes the injector down (Firing order is 1-3-4-2), adjust the ball screw.
Just to be sure you aren't over-tightening a ball screw, first make sure that the ball screw is loosened a couple of turns. When turning the ball screw against the ball pin, you will feel the resistance of the injector spring for several turns. When the injector bottoms out, you will feel additional resistance. Then turn the ball screw in the reverse direction 180 degrees.
5) Return camshaft to a position that both intake and exhaust valves for cylinder 1 are 'UP'. That is Camshaft Cylinder #1 TDC.
6) Turn crankshaft to the position that the crankshaft lock may be installed. That is Crankshaft #1 TDC.
7) Follow balance of PD timing belt installation procedure.
 

Richptl

Vendor
Joined
Jan 11, 2011
Location
Apalachin, NY
TDI
2004 Jetta TDI automatic 305,000 miles
Actually, for those who feel that using the cam to use as a rotating device, when we are replacing the cam, we ALWAYS turn the cam in order to set the ball screws. It is very fast and accurate. Of course, this is ONLY when the timing belt is disconnected.

As our procedure goes:
1) Bring the engine to TDC and remove the timing belt.
2) Replace the cam sprocket onto the cam pulley
3) Rotate the CRANKSHAFT backward 90 degrees (1/4 turn)
Now you can rotate the camshaft freely without any valve striking a piston.
4) Rotate the cam clockwise. As each rocker pushes the injector down (Firing order is 1-3-4-2), adjust the ball screw.
Just to be sure you aren't over-tightening a ball screw, first make sure that the ball screw is loosened a couple of turns. When turning the ball screw against the ball pin, you will feel the resistance of the injector spring for several turns. When the injector bottoms out, you will feel additional resistance. Then turn the ball screw in the reverse direction 180 degrees.
5) Return camshaft to a position that both intake and exhaust valves for cylinder 1 are 'UP'. That is Camshaft Cylinder #1 TDC.
6) Turn crankshaft to the position that the crankshaft lock may be installed. That is Crankshaft #1 TDC.
7) Follow balance of PD timing belt installation procedure.
I am changing my injectors to PD150's. In so doing, I am pulling the glow plugs. This effectively eliminates compression and most of the force of turning the crankshaft. How would you feel about me turning the CAM counter-clockwise in this instance? Since the crank pulls on the cam clockwise, the cam would pull on the crank counter-clockwise, so as to not pull on the tensioner side of the belt.

I would like to do it this way for 2 reasons:
1) Can watch the position of the intake lobes more easily if I am at the camshaft bolt.
2) I have a skid plate and metal side shield, both of which have to come off for me to get at the crank bolt.

My instinct is that with the glow plugs removed, more force is required to turn the camshaft than to turn the crankshaft, so in this case turning at the cam with the belt on is actually less stressful on the belt.

Correct me if I am wrong.
 

oldpoopie

Vendor
Joined
May 14, 2001
Location
Portland Oregon
TDI
2001 golf gl, 2006 jetta, 1981 ALH swapped rabbit pickup, 1998 beetle
Never rotate the belt assembly via the camshaft in either direction.
 

Richptl

Vendor
Joined
Jan 11, 2011
Location
Apalachin, NY
TDI
2004 Jetta TDI automatic 305,000 miles
Roll the car while it's in gear, like discribed above.
I have an automatic so that won't work.

Can someone who can "think outside the box" chime in on my question? I really think I am correct in that with no compression, if the cam is turned CCW then less force is transferred via the belt to spin the crank than if you turn from the crank CW. Those valves and injectors take some significant force to operate. One thing though is the 2:1 speed increase from cam to crank, so rotating at the cam spins the crank at double speed, taking more torque as a result.
 

oldpoopie

Vendor
Joined
May 14, 2001
Location
Portland Oregon
TDI
2001 golf gl, 2006 jetta, 1981 ALH swapped rabbit pickup, 1998 beetle
:confused:silly shortcuts:confused:

How much time will that really save?

I can jack a car up, remove belly pan and side skirt in under 5 min.
Turn wheels hard to the right. Use two 10" extensions and a long handle ratchet and you can stand up, viewing the camshaft, while rotating via the crank.
 

jimbote

Certified Volkswagen Nut
Joined
Jul 10, 2006
Location
spiral arm, milky way (aka central NC)
TDI
Tacoma 4x4 converted to TDI
I have an automatic so that won't work.

Can someone who can "think outside the box" chime in on my question? I really think I am correct in that with no compression, if the cam is turned CCW then less force is transferred via the belt to spin the crank than if you turn from the crank CW. Those valves and injectors take some significant force to operate. One thing though is the 2:1 speed increase from cam to crank, so rotating at the cam spins the crank at double speed, taking more torque as a result.
even subtracting compression the rotating assemblies mass and friction is a load the cam belt was not designed for @ the crank teeth especially when your asking half the tooth contact/surface area to take on much more load ....think moment of inertia from crank, rods, flywheel, clutch (or TC) as well as friction from the rings and mass/friction of the accessory line
 
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Nutsnbolts

Vendor , w/Business number
Joined
Nov 1, 2001
Location
Weare, NH
TDI
2000 Jetta, Silver Arrow
In answer to your question, the piston rings will provide significant resistance to turning, especially at the mid-point in the cylinder where the piston's speed would be the highest. Compared, that is, to the rolling resistance of the injector rockers, the roll and slide of the cam followers, and the hydrodynamic slide of the cam bearings (which is also existant on the crank).

In addition, the injectors only pressurize/inject fuel when the solenoid is energized by the ECM to close the spill port in the injector. Therefore, it requires relatively little torque to turn the cam when the key is off. The crank sprocket on the PDs is not round, but slightly flat at 180 degree intervals to take the belt stretch into account when the injectors fire. I would think that the position of that flat area will make it even more difficult to turn the crank via the cam. Then, multiply the number of revolutions by 2 cam to crank, and the amount of torque required, and thus the amount of belt stress, is far greater by turning from the cam, even with no compression figured in.

-Rich
 

Richptl

Vendor
Joined
Jan 11, 2011
Location
Apalachin, NY
TDI
2004 Jetta TDI automatic 305,000 miles
I won't gamble then and I'll pull the belly pan and side shield and turn at the crankshaft. I am changing injectors and one thing I had in mind was to use my Frostheater to warm the block a bit. Hoping that the block will heat up a few degrees warmer than the injector body to help with getting the injectors out. Running the engine to warm it up runs warm oil across the injector, plus the spring makes heat, and the injector pump makes heat. I've seen in other threads that the injectors pull easier on a warm engine, and I think the Frostheater method might make a teeny bit of difference in temp between cylinder head and injector body. I can do the same thing to put the new injectors in. Any thoughts pro or con?
 
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