4-Cam Head Removal.

[john.harrill]

Quote:

Originally Posted by Alfisto Steve IMHO you don't want to go there on changing guides unless they check bad on a 24v engine or even a 12v engine. Valve stem seals yes and what ever valves are bent but only a guide if bad. Why I don't know, but valve guides on a 24v are priced very very high. I don't think this is a case of penny wise and pound foolish either. Even on the 12v I hardly ever find more than one or two guides that need replacing due to wear. Some get damaged if bending of a valve stem damages it, but usually only tulip end bends on minor valve to piston episode so guides check out OK. As for manifold stud nut now that it is rounded off have you tried to use something like a 12mm socket or one of those wire cable loaded sockets? Can you roll engine enough to gain access to split nut with a sharp chisel and hammer or air hammer chisel?

[john.harrill]

Quote:

Originally Posted by BlackAlfa I guess heat it with a torch is somewhat out of a question! One option that comes to mind is to detach the manifold from the downpipe (from under the car). But this would make taking the head out even harder if at all possible. For extensive work like this, I would be tempted to drop the engine and subframe down (since I've done it before), slide the whole thing out and work on it while it sits on the subframe.

[Del]

At 140,000 miles on the engine, it COULD be considered penny wise and pound foolish to not replace the guides, as they will be rather worn, and based on what I've seen with Alfa heads, they can cause premature wear on the new valve stems and also potential leakage past the seats.

However, have the guides checked out for allowable valve slop or misalignment, and if not too bad, it's your call. The car does have 140k miles on it, and maybe you don't plan on keeping the car that long. And,maybe Alfa has improved the quality of the 24v guides.

Using oil is not a function of the valve stems and guides being worn, but how well the stem seals are holding up. The ones on the 24v engine appear to hold up quite well, whereas the ones on the 12v engine, regardless of model Alfa (ie, GTV6, Milano, or 164, can either be quite good, or they can go in no time at all from new.

[MrT]

Quote:

Originally Posted by john.harrill There may be enough space to get a hack saw in there.

[BlackAlfa]

Quote:

Originally Posted by john.harrill Ok. I had one nut left where the manifold attaches to the head and I rounded it off. It is on the rear head, middle pipe, top stud. I had previously sprayed copious amounts of PB Blaster on it and let it soak. Any suggestions?

[Alfisto Steve]

Price comparsion for set of 24 valve guides for 24v - Alfa Parts $959.20, IAP $1080. (This is POUND foolish to spend this kind of money)

A set of 12 guides for 12v - Alfa parts $118.50, IAP $59.40 (penny wise).

You really think that is money well spent to replace a good used guide on a 24v engine at about 40 to 45 dollars a pop?

[john.harrill]

Quote:

Originally Posted by Alfisto Steve Price comparsion for set of 24 valve guides for 24v - Alfa Parts $959.20, IAP $1080. (This is POUND foolish to spend this kind of money) A set of 12 guides for 12v - Alfa parts $118.50, IAP $59.40 (penny wise). You really think that is money well spent to replace a good used guide on a 24v engine at about 40 to 45 dollars a pop?

[Alfisto Steve]

This just in from checking on Centerline's web site so maybe a price break salvation. They list 24v guides for $3.80 each. Maybe that is a real price break need to follow up on this with Joe Cab and Steve at Centerline as other prices way out of line. Click here: Centerline Products: VG194 Alfa OEM Valve Guide 3.0 V/6 DOHC http://www.centerlinealfa.com/cgi-lo...242+1213062178

HOLD THE PHONE this is a 24v valve stem seal not guides their web site picture and nomenclature in ERROR. They are going to correct. I knew it was to good to be true.

They do not have 24v valve guides.

[Del]

I did say that at this mileage, even though it would be proper to restore the engine if there was nothing wrong with the car otherwise, with the way these cars are disposed of nowadays, it is probably not within the budget of the average owner of one these cars to do anything other than the minimum to get it on the road for a few miles more before being parted out. I also did say that the guides have to be checked for damage, distortion, and wear to ensure you reduce the possibility of damage. It does depend on your definition of "good condition" compared to what the factory thinks.

I can't imagine why the guides cost as much as they do except as an attempt by Alfa to soak the owner, or encourage new car sales instead of rebuilding. What do other marques charge for similar guides?

[Alfisto Steve]

Quote:

Originally Posted by Del I did say that at this mileage, even though it would be proper to restore the engine if there was nothing wrong with the car otherwise, with the way these cars are disposed of nowadays, it is probably not within the budget of the average owner of one these cars to do anything other than the minimum to get it on the road for a few miles more before being parted out. I also did say that the guides have to be checked for damage, distortion, and wear to ensure you reduce the possibility of damage. It does depend on your definition of "good condition" compared to what the factory thinks. I can't imagine why the guides cost as much as they do except as an attempt by Alfa to soak the owner, or encourage new car sales instead of rebuilding. What do other marques charge for similar guides?

[Del]

I'm sure that the 24v guide price is purely artificially very high for whatever reasoning Alfa has (the Family owns the company which makes them?). I suspect one could get guides from other cars and modify them to work (turn down, ream, etc). Machine shops have been doing this for years.

[john.harrill]

Had to hand-saw the exhaust stud off.
Everything is now loose, except the head itself.

The CarDisc is short on details. I removed the head nuts and everything else you would normally take loose, however the front (passenger side) of the head does not want to lift.

Is there something connected near the front of the head that I'm missing?
Oil pump related, maybe?

Also: The rear engine mount is unbolted, as is the transmission mount. I tried to tilt the engine with a transmission jack and a piece of wood, but it will only lift about 1/4 inch.

??

[Alfisto Steve]

You have to remove nut from oil pump shaft on rear head so head will lift off of oil pump shaft. So remove cover over it. It is one oil seperator drain line hooks to (where dizzy would go on a GTV6 or Milano engine.

Remove upper engine mount dog bone if not already removed. Also remove rear cam pulley, aux shaft oil pump pulley for clearance, transmission shock strut behind air cleaner area.

You got front head off, alternator clear, top radiator bracket off, false firewall out?

[john.harrill]

Ah, there it is.
I got the cover off and the washer out, but I cant get the intermediate gear out. If the nut is removed from the shaft, can the gear come out with the head?

I have the alternator out but the radiator and cross member are still in place.

[MrT]

My take on it is that the 90 degree meshing gears just come apart when the head is lifted away; that is, if the nut/washer (or flange washer) is removed. That is how I vaguely remember my wife's 12V engine going back together, and I think the general mechanism is the same for the 24V engine.

Michael