A complete magnesium 2.7 engine restoration

juankimalo

Posted November 7, 2005

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Posted November 7, 2005

:oops:

Hi everybody

This is my first thread in this site.

A complete magnesium 2.7 engine restoration

This is a nice story. Our friend David, has made a great job on this engine.

We are talking about a Porsche 911 2.7 (1976).

This restoration was made in 'Talleres Altozano' in Colmenar Viejo (Madrid Spain) where you can find one of the best Porsche specialist in Spain.

It was published by David (his nick in the forum is Barrichelo) here http://www.pasionporsche.com/foro/phpBB2/viewforum.php?f=1 on the www.pasionporsche.com forum, which is the most popular and interesting Porsche forum in Spain

(I’m the one who translated the whole thread from Spanish to English, with a little help form Carlos from Spain, in order to post it here for you guys. So I must say that I am only the ‘transporter’ of this illustrated report.

Juankimalo

2 pics of the car:

The engine was in very bad condition:

Here you have the engine out to work in:

Unistalling the admission and ignition:

Oil cooling kit:

The engine oil’s leak was previously sealed by someone with silicone, this is a very dangerous operation and should never have been done!!!!

To solve the leaks of the magnesium carters, we’re going to replace them by an aluminium one, from 930 turbo model. You only need to replace the lower carters.

The chain’s rail will be replaced by a complete kit from the 911 3.2 model:

The gear box was in good condition. Only needs new side holders in the transmission, and a new primary seal, and the rear main seal. Besides we’ll add new valvoline, including a whole detail cleaning with the high pressure karcher machine:

To catch the engine on is an easy task in a flat 6. You only need to withdraw the sparkplugs and to introduce a long screwdriver into the cylinder number 1 (can also be done with the number 6), you turn the engines pulley until the cylinder nº 1 stands in the upper break-even point (neutral position), in other words, the screwdriver remains completely out, and the mark of the pulley of the crankshaft is aligned with the framework of the turbine’s fan. The spark leaves directly for the first cylinder:

There were 3 different sparkplugs. A flat six can never work properly in that case!!!!!!!!!

Magic David (Barrichelo) “the hero”:

This is a Dansk sport exhaust, which will bring acoustic pleasure to owner from the moment he starts the engine....

We’re going to replace the injection accumulator of fuel pressure. Here you can see the sealant products and fixating products for the subsequent assemble of the engine:

Some pics of almost the all the parts after dismantling the engine:

There are still lots of some pieces to dismantle:

Now we’re washing the engine with the Karcher

It’s very nice to work with the engine being cleaned:

Here are the valve train and the oil pump:

And finally, the whole motor in little pieces:

Well, we have an amount of different spares, from Mahle; chain rails from Carrera 3.2, water cooler, new wires, motor joint...

This man is Mr. Emmanuel. David’s father, (a real artist in mechanical handworks). Although he is 69 years old and he is retired, he started with the tedious and delicate process of cleaning these fragile and fussy parts of the engine. If you make this task with the correct prevention, there would not be leaks in the future:

This is ready to receive the cases except the ones in the sweeping pump:

We’re going to assemble the whole cam. You need two people to make this task:

Previously, the state of the pump has been verified, and all the body has been retightened to avoid small internal leaks of oil:

New rubber rings, otherwise, we will lose pressure of oil. Be careful to place the rubber rings, an evil or unskilled placement of them can cause serious damages in all the lubrication of the motor:

New rear seal, and a joint for the forward headrest; the motor is almost ready to be closed:

Mr. Emmanuel is lubricating the mobile parts:

Look at the orifices of sprinkled of oil toward the bolt and chirped of connecting rod, they should not be blocked, verification:

What a small orifice...

A new group of rubber seals are ready to be assembled:

Let's begin with the special composite for the final sealing to avoid leaks:

Don’t apply too much composite:

It’s very important the way to apply the blue composite in the nuts to avoid the well-known leaks of the flat six:

Let’s see the result:

It’s essential to replace all the nuts, rings, and washers, for new ones.

Sweeping pump, new joints, and composite are ready. Of course new nuts and screws:

Everything is ready to be inserted:

The thermostat ready to be inserted has only one correct placement. You need a new rubber seal before insert it:

New cylinder head gaskets:

The piston is ready to be inserted into the shirt in the correct manner.

After that we proceed to introduce the assembly in the motor, previously tightning all the dilavar head studs of the block with the specific tool.

Then strike delicately with a rubber hammer:

Upper view:

We will place a stop in a dilavar head stud to avoid an unexpected turning of the body:

Try to be very careful in the way the piston engine brakes are inserted:

It’s very important add a little amount of lithium grease in the base of the cylinder to avoid the joint getting stuck:

We then place the joint in the correct position:

Here you can see the accurate location of the piston rings:

Before introducing the bolt, this should be perfectly lubricated, like the connecting rod. This action requires great precision and extreme sensibility:

Before placing the covers, we mount the deflectors of ventilation. Warning: its correct positioning is indispensable:

First we place the central one:

Lower view:

Upper view:

Ready to install the cups:

Ready the valves, seats, rails and valve springs retainers:

Inserting aluminium cylinder head gaskets to avoid oil leaks:

A litlle bit of lithium grease to fix it:

Warning: be very very careful with the dilavar head studs to avoid breaking them:

When you have to tight the nuts, you would need a different number of rings:

Tightening the cylinder head complete...

It’s a 2.7 engine of 1976 imported to Spain from Venice Beach!!

First of all we are introducing inside the holes, with a specially care to avoid making any fissures.

Once added the composite number 571 in the base of the seats we place it with the help of a rubber-hummer head.

Here we place then new18 nuts by cup, the total number is 36, plus the former 24 ones, so in total that makes 60 nuts with their own tightening order.

Subsequently we are going to begin with the Crankdrive. You can appreciate in the pic some of the elements involved. We can see the 6 chain rails (in the photo there’re only 5, ‘cause one of them was mounted with the engine). 5 of them are black and the other one is light brown . It is due to the extreme force that produces the friction of the chain in the right side of the upper angle. That excessive force makes it weaker and that’s why the material should be of greater resistance to avoid its break:

The cover of the cranckdrive (in the right side of the photo). They should be cleaned up properly with sandpaper extremely fine, to withdraw any impurity or residue:

In the rear envelope we have to seal the chain rails nuts, with grey composite to avoid the awful oil leaks.

Let’s see the detail:

After withdrawing this zone, we apply the composite:

An here is the result:

The cam cover gasket kit of the crackdriver:

The light brown chain rail. We place it before installing the cover of the crankdrive, both the upper and the lower one.

Be careful not to drop it inside the engine!!!

We place the fixing-pins with new rings and blue composite to avoid oil leaks.

Accuracy:

Upper chain rail:

We have to insert the distributor cap and the chain at the same time:

Before mounting the camshaft you have to measure it, and check the wear . Besides you have to lubricate the upper supports of the cam.

Just like that:

You have to tigthen the cap with new nuts , but you can never be too careful to avoid break this delicate piece.

We place the chain rail in the correct position:

The cover ring of the camshaft needs a new rear joint and new joint rings:

This is VERY IMPORTANT. If not oil leaks will surely appear

Rear joint:

After set it in its place:

The adjustment rings are 4 very thin and a conical one. First let’s insert the conical one and after that, the last four :

The chain wheel and the mounting the halfmoon

We are going to set this chain wheel properly to win some extra bHPs:

Here it is the chain wheel

We place the timing chains divided, and after that a new joint ring and the new chain tensioners.

New bolts, rod bolts, with new rings, and screws:

It’s important to check one by one before mounting. Its important that the inside

bronze case is not scratched

Let’s check for any the weakening of the half sphere:

The surface of the rod bolt must be without any wear:

We will begin to install the left cam:

Here you can appreciate my finger pointing at the orifice of the hydraulic tensioner . The oil pressured will go into this orifice to lubricate the tensioner.

The center finger is pointing at the fixing-clip of the piston:

All 911 models after 1984 were furnished with hydraulic tensioner. The tensioners are connected directly to the oil circuit. The result is a higher service life of the tensioner kits for all older 911 models

Here you can see new oil pipe lines to make a conversion to a 3.2 model:

Detail of new covers to place the new hydraulic chain tensioner:

Before installing the rod bolts, you ought to turn the engine 90º with regard to the original mark Z1 (upper neutral position of the cylinder number 1) until the six pistons would are positioned in half-stroke to avoid the valves brushing the rod bolts.

We insert them one after one when the valve rod would be in neutral position .

Let’s apply a little bit lithium grease on the case and oil into the bolt.

Snap, snap, snap , and It’s placed in its correct position:

It’s very easy:

Now let’s go with the casings on each side One of them is made to be tightened with the allen head

Let’s tighten:

Valve adjustment: 13 thousandth:

The new oil cooler:

New joints and of course a bit of 574:

The uppers:

Inserting...:

We got the whole Danks set. It’s stainless steel made, probably eternal. So the owner will never have to worry about that:

We are going to raise the seating of the engine with a new opening adjuster:

View:

When the opening adjuster shows an opening of 10 thousandth we can set the engine in order its chain wheel. Once fixed the piston you can remove the screw:

The stop of the adjuster is touching the spring head:

Once made the setting of both cams we will tighten the two valve rods:

After that you do the same with the other valve rod:

The engine is ready to receive the covers and the complete chain tensioners lubricant kit

The original covers were made in magnesium, and we are going to replace them by aluminium ones. One of the main problems of the magnesium covers is the higher coefficient of expansion, and therefore cause oil leaks . The upper ones is not necessary to replace them.

Before closing the covers , we place the adjustment joints in the chain tensioners:

We can see the new oil pipe lines kit to lubricate the chain tensioners:

Left cam:

At now the closing up is very easy. Wires and more wires…:

Let’s begin to mount the turbine cooling kit:

Turbine:

Wiring of the engine previously reorganized and verified :

New wires, ignition, distributor connects and caps, side protectors...:

The injection system was installed in its place. There are some little details left, and of course the clutch kit.

Before setting the engine in its place (rear boot) we are going to make a detail work in order to wash the boot up with the high pressure karcher machine

Besides, we are going to replace the rear shocks (Bilstein)