Well its a while since I sourced and received my new cylinder head and my lack of knowledge regarding what can be transferred from the existing cylinder head to the brand new AMC one.

I know I have already asked for advice regarding this but I must get it sorted now after sitting for 3 years plus I have never attempted this precise critical type of work.

The car has I suspect has still got its original cylinder head the car has covered 71,378 miles with full-service history prior to be laid up (started every 2-3 weeks)

I do appreciate I must fit new valves and springs and valve seals, new head gasket along with new stronger head bolts.

I have a brand-new AMC camshaft kit with hydraulic tappets, cam shaft seal.

Should I re use the existing rocker arms/bolts or will they be too worn for new valves/ camshaft.

Will the injectors require re conditioning or can they be simply re used as is with new seals.

I intend to fit new Gates cam belt water pump kit, engine oil and coolant.

I have a timing locking kit.

I need 5 new tyres as well so would like to keep costs to a minimum where sensible/possible.

I intend to keep it for a while when sorted or until older diesel vehicles are priced off the road.

 

Oh and I have approached several local garages who initially didn't want to carry out the works 3 years ago.  

Anyhow I look forwards to help with the above thoughts.

Martin. 

 

Actually you can reuse everything from your old head that isn't damaged, the main problem you have is that the valve seats will need cutting to suit whichever valves you're using. I assume you're replacing the casting due to cracking or warping. Please advise.

8 minutes ago, sepulchrave said:

Actually you can reuse everything from your old head that isn't damaged, the main problem you have is that the valve seats will need cutting to suit whichever valves you're using. I assume you're replacing the casting due to cracking or warping. Please advise.

Hi sepulcrave, the head that is on the running engine has suffered from head lift putting exhaust gasses into the expansion bottle -chemical tests confirm.

I thought that new valves would only require fine grinding in with paste due to the new cylinder head being supposedly one of best quality available with appropriate valve seats already cut.

Good to know about the other head parts.

Martin

21 minutes ago, kentdale said:

Hi sepulcrave, the head that is on the running engine has suffered from head lift putting exhaust gasses into the expansion bottle -chemical tests confirm.

I thought that new valves would only require fine grinding in with paste due to the new cylinder head being supposedly one of best quality available with appropriate valve seats already cut.

Good to know about the other head parts.

Martin

 

You can try fine grinding, you'll find out very quickly if it's gonna work or not, just replace the valve stem and injector seals together with all the stretch bolts.

...don't forget to set the injector lash and lock the cam before fitting the head to the engine.

 

Replacing all the stretch bolts means replacing ALL the bolts for the cam caps, injectors and rocker shaft, the rockers themselves should be fine though. Use assembly lube on everything that touches moving parts under pressure, lots of fresh oil everywhere else.

3 hours ago, sepulchrave said:

I assume you're replacing the casting due to cracking or warping. Please advise.

He is doing the right thing no matter what. If you take off a cylinder head it is accepted standard practice to give it an as light as possible reface BUT VAG now scream very loudly about not doing this “cylinder head must not be reworked”. The reason is the heads are HIP heat treated (Hot Isostatic Pressing) and refacing removes this so increasing porosity. This is why you read people saying “I had the head gasket done two years ago and it has gone again”. I have used AMC heads for years with totally reliable results. I have used genuine VAG exchange heads on the ASZ and ARL, you can see these have been refaced and reheat treated, it has an almost gloss lacquer type appearance rather than the typical satin skimmed finish.

1 hour ago, Crasher said:

The reason is the heads are HIP heat treated (Hot Isostatic Pressing) and refacing removes this so increasing porosity.

Machining cannot create casting air bubbles that the HIP process has previously expelled.

 

There must be a reason but it wont be that, most likely to avoid removal of the post HIP hardened and tempered layer.

1 hour ago, Crasher said:

He is doing the right thing no matter what. If you take off a cylinder head it is accepted standard practice to give it an as light as possible reface BUT VAG now scream very loudly about not doing this “cylinder head must not be reworked”. The reason is the heads are HIP heat treated (Hot Isostatic Pressing) and refacing removes this so increasing porosity. This is why you read people saying “I had the head gasket done two years ago and it has gone again”. I have used AMC heads for years with totally reliable results. I have used genuine VAG exchange heads on the ASZ and ARL, you can see these have been refaced and reheat treated, it has an almost gloss lacquer type appearance rather than the typical satin skimmed finish.

 

Dude please, we used to use AMC castings whenever we could get them for the professional machine shop, the problem was getting the supply, particularly for the Discovery TD5 which had an absolutely shocking OE casting. 

The valve seats on the PD head are slightly pocketed to allow room for skimming with the valves removed, so it's not what you think it is.

21 hours ago, J.R. said:

Machining cannot create casting air bubbles that the HIP process has previously expelled.

 

There must be a reason but it wont be that, most likely to avoid removal of the post HIP hardened and tempered layer.

 

I read it someone in a VAG Self Study Program but can't find it again, ELSA just says don't.

1 hour ago, Crasher said:

I read it someone in a VAG Self Study Program but can't find it again, ELSA just says don't.

 

You have to accept that VAG best practice will differ from standard engineering practice on the basis that a retail customer will be paying the bill and no engineers whatsoever will have been involved at the dealer level.

 

The engineering shop I worked for had accounts for every single dealer in our catchment area, VAG included!