Porsche 928 S

OK,It’s almost a mercedes, it has a Mercedes three speed automatic and the engine fan carried a W108 part number….

Recently purchased by a new owner ,I was asked to do a pre purchase inspection. The car looked OK but the seller had problems getting it to fire… 10 years off the road is not good for any car.

 it was delivered here so i could take a look at the4 engine and get it ready for the owner so he could drive it to Sydney.  I got the engine running but there was terrible knock from number 2 cylinder and several cylinders were misfiring. A leak down test revealed at least three intake valves were leaking badly. So off came the heads…to reveal a badly damaged bore in #2 . The ringas must have been stuxck to the cylinder walls ansd whwen the PO tried to start the long dormant car,the rings grabbed breaking some of them and then breaking the piston.

 Up date: a new engine has been sourced from local 928 tuner,John Gill and this is undergoing a re ring and reseal prior to fitting to the car,

 ist picture shows the replacement engine as it arrived here, it was full of oil,really full so i had to tip it over and pour it out of the cylinders. It had been oiled up to preserve it. 

3rd pic shows a lot of the blackness inside .

4th pic,heads removed .Bore is OK .

5th,the pistons and rods are removed to reveal perfect bearings and crank 

6th pic,not so good in cam department though. I loosened the timing belt ,then undid the cam gear retaining bolts. the left hand cam wheel fell off when i undid the bolt. 

There are a few theories regarding the reason for this, but my own is that the edge of the step ,where cam wheel butts up to cam has a sharp corner , which is a stress point that creates cracks  ,and that is where the cam has broken off.

7th pic is of the only dodgy piston,number 5 where the rings were stuck in the grooves.  The rest of the pics show the heads reassembled and the Kjet intake manifolds wet blasted to restore the original look. 

 

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