Testarossa injector removal

Many Testarossa's that are constantly driven on snow covered roads or in inclement weather are likely to look like this after a while. Near total neglect!
Check the fuel lines, rusty and pitted. Original steel injectors will rust to the fuel lines and the steel spring clip that holds the injector collets into the manifolds will rust badly.

This generally causes the aluminium injector collets to seize against the manifolds and they can be a right royal issue to get out.

First step here is to remove the fuel distribution units and put aside to be cleaned up later.

Then remove the old fuel lines and the large spring clips holding the collets into the manifolds. Soak them for a day or two in Penetrene as required.


The picture below shows the manifold with collets removed. If you can't get them out, remove the manifolds from the engine and grab a
large drift punch of a size that just fits up into the collet hole from below.
Support the manifold against a flat surface and drive the old collets out from below.


Expect the collets to be in quite bad condition, as can be seen here. Some will have the entire groove where the large injector 'O' ring sits completely worn away. New collets are available ex Factory, but they were too expensive for me. I purchased a length of 6060 aluminium and had a local engineer fabricate me a new set. The lower small 'O' ring is available from any bearing supplier, but the large (fat) one is only available ex Ferrari or possibly from Bosch.

The image on the right is one of few good collets removed from my car. Note the large groove where the fat 'O' ring sits to hold the injector unit.



My new injector collets all ready to accept the new brass injectors.

Note the very fine 'O' ring in the bottom of the collets.
Both the small bottom 'O' ring and the outer 'O' ring were purchased locally for a bearing supply store.



Next step was to replace the injectors after getting the old steel ones flow tested and finding them all either leaking or not spraying properly.

Ferrari changed from steel injectors to brass units in 1990 due to rust issues with the fuel lines. I cross referenced the Bosch injectors and found that ALL petrol Mercedes from 1979 to 1988 used exactly the same injector as Ferrari used to supersede the old steel units. I picked up 12 from a local Mercedes parts centre for the princely sum of $35 each. Testing them on a flow bench prior to fitment showed a perfect atomization pattern irrespective of the line pressures.