Lamborghini Countach 5000 (JC)
Full engine rebuild
Restoration log by Dan Mooney



Full engine rebuild


Update report - November 16, 2023
We have established that your connecting rods are not a matched set. Unfortunately two of the rods have obviously been replaced at some point in the past. Those two rods have a very different weight at the journal ends than the other ten. In the circumstances I would recommend that we obtain a replacement set from Carrillo or Pauter.

Update report - November 9, 2023
We have the engine tear down well underway and have already discovered some significant issues. One of the first things we noticed were mismatched cylinder head gaskets. The right hand cylinder head gasket was leaking, largely due to excessive liner protrusion (.009") from the deck surface of the block. The left hand cylinders were all within spec between .003" and .004". The cylinder bores are standard size and are also out of round, as evidenced by the shadowing in the photograph below. Valve stem to guide clearance was excessive.

We have already designed and ordered a set of new forged pistons.

Coolant in oil pan.

Copper showing on rod bearings.

Main bearing damage.
Front cover expoxied.

Excessive guide clearance.

Cylinders shadowed and out of round.

Mismatched head gaskets.

Guides removed.

Update report - September 28, 2023

Update report - September 20, 2023

Update report - September 12, 2023