Audi A4 new engine or just cylinder head?

[iandandav]

The valves must be perfectly straight, with the heads concentric on the stem....in fact in early engines the camshaft lobes were slightly off centre to allow them to rotate a little - not necessary now.
Taking the valves out is dead simple using a valve spring compressor - yours will likely need the deep recessed type that Laser tools do.
On top of each valve stem will be an oil seal that will need replacing - these are cheap enough.
If your tappets aren't hydraulic, the cam to valve clearance will need to be set too.
John

Thanks Burnerman, as I thought more specialist tools and more effort than I have in me at the moment. Loos like a new reconditioned or second hand head. Do you know a good source?

 

[iandandav]

A secondhand head will be the most cost effective approach, especially if
your pressed for time.

As already mentioned get it skimmed and a new head gasket. We have
reused the head bolts in the past without trouble. But might be best to
replace them if not to expensive?

Good luck

Yes I think this is what Illl do. Thanks

 

[Mursal]

Do a google search for "find a part.co.uk" and pick the closest to you.

If still in trouble try"find a part.ie" but the carriage will more expensive.

www.traynors.co.uk

Allot of the breakers will not like to split a good engine.

 

[iandandav]

I mentioned to someone on a different forum (not cars) that when two of the pistons were tdc the other two were half way down. He said that they should be all tyhe way to the botton. Is this correct? as I was sure they were only half way down, but I could have been mistaken. I cant check the car at the moment as its in a relatives garage.

 

[Burnerman]

I can't see any 4 cylinder engine having this arrangement - it would be chronically out of balance, surely?
John

 

[Mursal]

If one piston (No1 the one nearest the front grill) is flush with the top of the
cylinder block at Top Dead Center (TDC) but its companion (No.4) is down
a few millimeters then you have a problem?
Likewise if No.3 is flush and No.2 is down a few millimeters you have a
problem. As this will indicate a slight bend in the connecting rods which will
leave the engine hard to start, due to low compression. As already
mentioned very unlikely in your case.

Don't worry about what the other two pistons are doing.

 

[iandandav]

My mistake, when pistons 1 & 4 are up top, 2 & 3 are at the bottom. Also each piston is at the same level as its partner.

Got the valves sorted at a piston specialist place in cardiff. £330 replaced all twenty valves and some other components associated with them, new cylinder head bolts and a gasket. They cleaned it up nice too. Good service.

Put it back on today and waiting for the battery to recharge, will try it tomorrow.

Is there anything important I need to do before before trying to start it besides water and oil. Should I pump the accelerator or would this confuse the fuel management system?

 

[dpsservices]

have you rotated the engine by hand to make sure it turns freely?

 

[iandandav]

have you rotated the engine by hand to make sure it turns freely?

Yes I turned the crank shaft bolt clockwise and it was stiff but turned getting easier as reached tdc

 

[dpsservices]

re check timing marks if so just fire it up, i always just flick the key the first few times just to be sure lol

 

[iandandav]

Well it didnt start. It drained the battery really quickly only able to turn it over about 5 times before the power got too weak. Could this be because it would take time for the ful to get through.
Im starting to worry that the valves are not in sinc with the pistons so I double checked the timing marks and thety were ok.

I dont know about how the valves were replaced. Is it possible that they can be put in wrong or the cam shaft on incorrectly? A professional piston place did the valves so it should be correct.

Does anyone know if the cam shaft sprocket has to be removed when changing the valves. Im thinking that if they put the sprocket back on incorrectly the tdc mark on it may be in the wrong place. Is this possible?

 

[Burnerman]

Its by no means certain that the cam sprocket is keyed onto the cam, but of course in the good old days they always were....this is so the valve timing can be more accurately set. The cam would be removed for work to take place.
Easy enough to check though - if it is keyed then you can rest assured that its in the right place.
A general check is to set No 1 cylinder at TDC and slowly turning the crank...the inlet valve should open immediately and be fully closed on the next up stroke, which is compression. When the piston reaches BDC on the power stroke, the exhaust valve should be open as the piston rises again. Bit rough and ready, but it'll give you some idea.
John

 

[Mursal]

Check all your plugs are connected to all sensors?
Thee oil filled tappets (in the head) that operate the valves will have to fill
with oil.

Have you oil pressure yet?

AS far as I can see in the Haynes manual the pulley is keyed to the
Camshaft. But its an older engine than yours (20 valve 5 cylinder)

 

[iandandav]

Its by no means certain that the cam sprocket is keyed onto the cam, but of course in the good old days they always were....this is so the valve timing can be more accurately set. The cam would be removed for work to take place.
Easy enough to check though - if it is keyed then you can rest assured that its in the right place.
A general check is to set No 1 cylinder at TDC and slowly turning the crank...the inlet valve should open immediately and be fully closed on the next up stroke, which is compression. When the piston reaches BDC on the power stroke, the exhaust valve should be open as the piston rises again. Bit rough and ready, but it'll give you some idea.
John

Thanks Burnerman I will check that. Do you know looking at my 3rd pic on my earlier post which are the exhaust and which are the inlet valves?

 

[iandandav]

Check all your plugs are connected to all sensors?
Thee oil filled tappets (in the head) that operate the valves will have to fill
with oil.

Have you oil pressure yet?

AS far as I can see in the Haynes manual the pulley is keyed to the
Camshaft. But its an older engine than yours (20 valve 5 cylinder)

I just put the head straight on I didnt put any oil in the tappets or do you mean they will suck it up after the engin is turned over a few times? I dont know if I have oil pressure. Would this be done just by looking in the oil cap and seeing if its running