Jobs when the head is off?

[wil892]

I'm taking the head of the GTD this weekend to replace the headgasket and all the other gaskets.
I'm currently lowish on money, but would like to do any preventative maintenance I can to the head and other things while its off.
I will be taking the head to be refaced at a very well known vw engine rebuilder/redesigner. Should I have any parts of the head replaced. The car runs absolutly perfect, no blue smoke and only a light amount of dark smoke when at WOT. How long do the valve guides last? Do the stem seals usually go like the 8v petrol engines? Should I have the valves re-lapped?

I've bought a new HEPU water pump
Timing belt
expansion tank
Genuine top end gasket set (inc valve seals) and other seals
All filters and fluids
Will buy 1.6td fibre gasket when i know the protrusion
Head bolts

Before I take the head off I'll be running a litre of diesel purge through it to clean the pump and injectors.

Also one last thing, i'm not really sure how i'm going to remove the turbo, however is it possible to just remove the four bolts that connect it to the downpipe instead of removing the spring clips which i don't have a special tool for.

Thanks
Will

[Smokey Eddy]

Yes you can just remove the turbo from the manifold.

I'd spend the 20$ or what ever it is to get the right polishing bits for a dremel (or drill) and polish the ports of the head.

WORLD of difference.

This is what i did when i took my head off
http://vwdiesel.net/phpBB/viewtopic.php?t=16482&postdays=0&postorder=asc&start=90

Page 8 is my favorite.

[dieselweasel]

Just disconnect the downpipe from the turbo by removing the 4 nuts.  Remove the head with the turbo attached.  Get your engine builder to go over the head to make sure everything's in spec.  If there's even a slight chance you might install a pyrometer in the future, drill and tap the manifold when the head's off.  You can just put a pipe plug in there for now until you install a thermocouple.

[arb]

You should also spend the $50 to replace the idler pulley if it was not part of a set for your timing belt. The originals only had a recomended interval of 50,000 miles. I would not go beyond 100,000 miles in any case. Its much easier to R&R now than later.

[wil892]

Thanks for the replys. I was looking at it today and did wonder whether i could just remove it with the turbo attached. Thats a relief, i am really not a fan of a bad back just to remove all the bolts back there.

I was thinking about just cleaning the face of the head up now seeing as the gasket is not blown and shouldn't be warped but would everyone recommend I take the head to the VW engine builders to be checked and refaced.
I could possibly get the manifold tapped there as well as I don't have any tools to do that.

ps the belt tensioner was replaced about 10,000 miles ago with a genuine one. I have bought a new Dayco timing belt for it, are these ok or should i have bought a contitech?

[dieselweasel]

Why are you going to take the head off if you don't think there's anything wrong with the head gasket?

[Smokey Eddy]

remember, the head it's self is very light compared to the cast iron exhaust manifold and turbo. Just be weary of that so you don't damage the mating surfaces.i lifted mine by grasping the turbo with my strong arm and putting a finger through the loop on the head with my other. I almost always get a friend to help though. I don't try to be superman when there are mating surfaces such as that of the allum. head involved. Even if you're using a crane be very cautious of that killer unbalance.

[wil892]

I'm taking the head off because as far as I know the gasket has never been changed and the engine was sat for a period of 1-2years. Also it is leaking oil from the front and the rear pretty badly and is also leaking some coolant out the side.

Thanks smokey eddie for the advice. I stripped off a load of stuff today and am almost at the point of removing those four exhaust bolts and then removing the head. Is it possible (by this i mean using a socket set) to remove the manifold from the head, as it would proabably be a lot easier to just leave the turbo alone rather than disconnect it all. My dad can help me with removing it.

As far as positioning the new head gasket goes I was going to chop the head off two head bolts and place the new gasket onto the block then put the head on and remove the old bolts. I'm not sure how I would remove the old bolts from the head though when the head is on. does anyone have any better ways of accurately placing the head and gasket?

Thanks
Will

[dieselweasel]

Is it possible (by this i mean using a socket set) to remove the manifold from the head, as it would proabably be a lot easier to just leave the turbo alone rather than disconnect it all. My dad can help me with removing it.

As far as positioning the new head gasket goes I was going to chop the head off two head bolts and place the new gasket onto the block then put the head on and remove the old bolts. I'm not sure how I would remove the old bolts from the head though when the head is on. does anyone have any better ways of accurately placing the head and gasket?

That's what I did...cut the head off two head bolts to act as guides.  Simply cut slots in the bolts and they can be removed with a screwdriver once the head is in place.  Just be careful you don't hit the head on the studs on install...as Smokey pointed out it's easy to damage the aluminum.

I think you'll find that it's easier to disconnect the turbo and remove it and the manifold along with the head.  Some of the manifold nuts are not that easy to get to with the turbo on and then you'll still have studs sticking out of the head.  To disconnect the turbo, you just have to remove the nuts holding the down pipe on, disconnect the oil feed line, and disconnect the return line at the block.  Make sure to cap off the oil feed port of the turbo.

[wil892]

Well, after 4-5 hours  finding more and more bolts to come off (not a fan of watercooled turbos )I have the head off. All the bores are in excellent condtion, all the honing marks are still there and there is no lip to speak of at the top of the cylinder.
The head has very small cracks between the valves, but not anywhere near like those I've seen in pictures here.

One of the pistons has some brown solid powdery stuff on the top just either side of the little swirl indentation. Does this sound like a bad injector?
I'll post up some pics tomorow of all the bores and the head face if anyone wouldn't mind giving me some opinion on their state.

I can definatley see how easy it is to damage the head, luckily my dad is helping me, plus we've rigged up a sort of pulley to support the weight
will

[wil892]

having looked at the head earlier I've found some quite worrying cracks in the pre cups. here are some pictures. Think I'm going to look for a new head.

[subsonic]

The cracks between the valves do not look bad at all.  The crack in the pre-cup is pretty big.  If you can find another good one why not swap?  You other option is to find a good 1.9idi head and put it on.  AAZ or 1Y.  It is a direct bolt on.

[wil892]

by swap, do you mean swapping precups? It might be possible to source new ones over here in the UK. I'll ask the engine place tomorow as they are very good.

I do have another head which is bare with no guides and is an official VW exchange unit. I've just measured the pre cups in that and they are the same size but I'm not sure i've the head has been skimmed. The bare head does need skimming now as it has some pitting or cavitation in certain areas. Does anyone know how to tell if a head has been skimmed? If it hasent then I assume I could just swap the precups from the bare head to the current head.
Not a fan of having to buy a new head at the moment especially as it looks like I need new injectors.
Will

ps I can't really put a 1.9 head on as it would affect my car insurance as I would have to declare it.

[jtanguay]

ps I can't really put a 1.9 head on as it would affect my car insurance as I would have to declare it.

can't you just play 'dumb' and say that the person who sold it to you (at the wreckers) told you it was exactly like the one you took off???  i suppose the valve cover is noticeable different though... it would be the same as saying "it was like that when i got it" type deal  :wink: but i bet they would be dicks and make you find a stock engine or cancel the insurance policy  :roll:

here insurance companies ask if the car has been modified... i think i'm not alone when i say that i never mod the car  :lol:.

i think its pretty much impossible to tell if the head has been skimmed, unless it was a really shoddy job.  apparently though cracks in the swirl chambers are most likely due to skimming.  the proper procedure is to remove them and then skim the head, and then compensate by removing material so the swirl chambers go in deeper.  this ensures that there is still sufficient 'meat' in the swirl chamber to reduce or eliminate cracking from the heat stresses.

in europe it should be fairly easy to track down some swirl (pre) chambers.