Got the engine appart, crank mod?

[TD_vento]

I think you are wrong, when shaving the head you need to make up for this space somehow, the thicker head gasket is the solution.

the machinist told me that he removed 0.75mm off the head as it had wraped badly.  The new gasket i got was a 2 hole one, i think I might need something thicker.  Does the manual cover this?

[QuickTD]

lilypapa is right, the gasket thickness is determined by piston protrusion, it has nothing to do with the head. Since the head does not have a conventional combustion chamber you won't change the compression very much by machining it. The valve seats were likely machined at the same time, this will usually sink the valves into the head far enough that clearance will not be an issue. Technically, you are not supposed to machine the head because it upsets the relationship between the valves and the deck surface of the head, but for practical purposes it usually works out just fine. There really is no way you can make up the 0.75mm that was taken off the head anyway, the variation from the thickest to the thinnest head gasket is less than 0.4mm.

[QuickTD]

I like that you agree, but my user name is a libbybapa rather than lilypapa. Iv'e been called worse, though.  

My apologies, I will be more careful in the future... :oops:

[TD_vento]

Got the crank in the new engine, installed new big end shells.  Come to put thre rod bolts in i notice the dealer have supplied me with the wrong bolts.
There seem to be 2 types, 1 have 2 bumps on them and are longer 45mm thread and the others have 1 bump and are shorter.  Im waiting for the others now

A quick question, the thrust bearings have 2 channels on them each.  Im pretty sure that the channel should be facing opposite side from the bearing on the main end.  

thanks

[fspGTD]

When a head warps, it's not just the head gasket surface that moves... :shock:  You should give some serious thought to having your cam bearings align-bored.

[TD_vento]

Hmm it makes sense.  Any way to test the alignment before the head goes together?

[QuickTD]

Any way to test the alignment before the head goes together?

Remove the lifters, make note of the installed position so they can be returned to thier original holes, an egg carton works good for keeping them sorted. Then install the camshaft and see if it turns freely.

The grooved, silver side of the shell faces the crank, the marked side faces the main bearing.

[DieselMonkey]

Yes the guys are right, head gasket thickness is determined by the piston protrusion above the block. You should clean the piston tops and use either a DTI or depth micrometer to measure the depth.

If you had a factory car with 3 hole gasket this would simply mean that the surface of the block required slightly more machining to clean its surface, or maybe it didnt require it but thats what it got. When your dealing with cast iron and a face mill 12" in diameter... 0.1mm here / there is a reasonable target, compared to machining the likes of alu. in a CNC mill in which case you could quite easily hold a tolerance of 0.05, not +/- 0.1

Skimming an IDI head will increase the compression very slightly, as your removing material from the prechamber but also the recesses around the valves, but you dont really need to take this into consideration. On a DI the compression would change even less. Some engine builders would simply supply the thickest gasket to lessen the chances of a mistake, but if your car left the factory with a 1 notch, you had the head skimmed and you fitted a 3 notch, you would notice the cold starting ability change.

On the mk2 GTD I rebuilt (1.9TD), I only needed a 1 notch gasket, but because I wanted to run higher boost pressure, I installed the 3 notch and increased the boost to 1.5 bar. The car was no problem to start from cold with the glow plugs, but when warm it would turn over a bit longer than the others. No big deal, but it was noticable. You could always make adjustments to have the glow plugs operate above 70C.

When where on the subject, how does everyone feel about lowering compression when raising boost ? Most diesel manufacturers do lower compression slightly on turbocharged engines, for example Perkins engines used in agri. machinery, but how about the Finns who build the 350 - 400 HP Mercedes W123's and W124's (190 / 300). They run OM606, 3 litre straight 6 IDI's with compression of 22:1. Able to bring a turbo as big as a Holset HX40 to over 2 bar !

DM

[TD_vento]

I have a manual for TDI audi A3 and it gives the values for the gasket types.

Piston projection 0.91-1mm (1 hole gasket)
- -    -                0.01-1.10  (2 hole gasket)
- -            -        1.11-1.20  (3 hole gasket)

Now i dont have a dial test indicator to measure the height, ill use some feeler gauges for this.

Are those values above the same for the TD AZZ?
 
Also need to know the camshaft cap torque settings.

Thanks

[TD_vento]

HI guys, finally got the engine together installed everything.

I tried to crank it up but it wont fire, engine turns though.  I checked the timming 3 times and its spot on.  

Havent done a compression test as I dont have the tool but by turning the engine by hand I could hear the air compressing the same in all 4 cylinders.
I see the air bubbles in the inlet line to the pump so Im assuming diesel is flowing.

I will get some diesel starting spray tomorrow and give it a go.

What could it be?  Im not too experienced in this diesel engine or pump.

thanks

[TD_vento]

No Im sure the pump is in the correct position, there is only 1 hole on the pump pulley to align with the pump bracket, i used a bolt with similar diameter to keep the pulley in position.

[TD_vento]

Wanted to let you know that the car is now running sweet.  I found the problem to be a wrong conection on the pump, the 2 black wires which clip on the pump, I had them the wrong way around.
Thaks for the help guys!