Machining a cylinder head for a VW 1.6TD (Golf) - DIY

Hello,

I can finally replace my Z-axis lead screw (ZKS). Due to some minor scratches and to check for flatness, I want to resurface the spindle.
Has anyone ever milled their own head before (I have a milling machine)? What experiences do people have with that?


How far should I disassemble the head if I'm sending it in for analysis?
(Remove camshaft and pre-combustion chambers?)

I currently have a cylinder head gasket with 2 holes. After machining the head, should I use a 3-hole gasket, or only if a significant amount of material has been removed?




Kai.

Hello,

I once ported the cylinder head on a gasoline engine and then smoothed it out on a large steel plate using sandpaper. It was tight and worked great! The problem is, you don't know how much material you can safely remove. After 600 km of full throttle, I had a hole in the piston. But it ran like crazy . Based on that experience, I would rather avoid doing that.

Okay, you can definitely go with a 1/100 offset without any problems. With my old TD engine, I also replaced the swirl chamber and reduced the head height by about 6/100 mm. The only thing that happened was slightly higher compression, but you won't get more power from that in a diesel engine.

Hello,
Okay, I would probably leave the milling machine out of consideration! A surface grinder with peripheral grinding is definitely more suitable! Keywords: Elb or Jung! And the clamping process isn't as problematic there either .

Best regards, Robert.

Hello,

mueller900 wrote:

Aufgrund von leichten Riefen und zur Kontrolle der Ebenheit möchte ich den Kopf planen.

Get a straight ruler and check the sealing surface for flatness. If it's still within acceptable limits, leave it as is. I wouldn't bother re-working it because of a few scratches; it will seal just fine anyway.

Quote:

Has anyone ever milled their own head before? (I have a milling machine). What experiences are there with that?

"I agree with Robert; it's about getting a verschandeln surface, not trying to tune a gasoline engine by milling off a millimeter."

Quote:

How far should I disassemble the head if I'm sending it in for machining? (Remove camshaft and pre-combustion chambers?)

"Just leave the chambers in place. The camshaft needs to be removed, otherwise the valves will remain open. I would also remove the valves because otherwise debris or grinding dust might get stuck in the valve guides. You can't dry-grind aluminum because that would clog the disc, and water splashes with grinding dust always find a way to where they don't belong."
If you're already doing it, you might as well replace the shaft seals and, if necessary, the valve guides yourself.

Quote:

I currently have a cylinder head gasket with 2 holes. After machining, should I use a 3-hole cylinder head gasket, or only if a significant amount of material has been removed?

The piston protrusion doesn't change; only the compression ratio increases slightly because, so to speak, the valves move closer to the bottom of the pistons. So, you can hold it like that on the roof . I always go for a size 3 anyway, due to increased boost pressure.


Best regards, Uli.

Thank you for the information.


I'm not going to do the milling. If I expand the chambers and mill the head, I'll end up with a step or ledge. Milling both parts won't work either.

I will start by measuring the flatness with a ruler.

The third cylinder wasn't just damp, it was quite wet. This was clearly visible during disassembly. The head gasket is partially 'baked on,' but not completely torn or anything like that.

A car mechanic I didn't trust told me: 'You'll see it when water leaks through - the head gasket was still okay.'

Bitte gib mir den deutschen Text, den du übersetzt haben möchtest.
He couldn't tell me how the water got into the cylinder and then through the exhaust system.

Hi,

mueller900 wrote:

A car mechanic whom I distrust told me: "YOU'LL SEE THAT WHEN WATER GETS IN" - THE HEAD GASKET WAS STILL OK. He also couldn't tell me where the water was coming from and how it could get into the cylinder (and then through the exhaust system)

.

"In some cases, when the cylinder head gasket fails without any other apparent issues, the mandatory cracks between the valves can sometimes extend all the way into a coolant channel. You'll notice this by seeing the water in the expansion tank turning black. I once replaced the head gasket on an AAZ engine, but it was still exactly the same afterwards. Then I put on a new cylinder head, and that solved the problem. However, if you can get the gasket and bolts cheaply (e.g., buying them immediately from motorensuche.com on eBay), it's worth trying before you buy a completely new cylinder head based on suspicion."


Best regards, Uli.

'In these cases, the mandatory cracks between the valves can sometimes extend all the way into a coolant channel.'


I still believed there was something good about my 1.6-liter engine.

Nun brauche ich einen neuen Kopf.

Does anyone have experience with the 'heads' that are offered for sale on online marketplaces for €239?


Kai.