Snap Quiz

Started by bazzbazz, February 11, 2023, 11:54:46 AM

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bazzbazz

So, was doing a cambelt change on a clients car the other day, when I pulled the cambelt cover off  lo and behold i was confronted by this -



Anyone want to guess how this happened?  :o
On The Spot Alfa
Mobile Alfa Romeo Diagnostic/Repair/Maintenance/Service
Brisbane/Gold Coast
0405721613
onthespotalfa@iinet.net.au

poohbah

#1
Something bad, or stupid.
Now:    2002 156 GTA
            1981 GTV
Before: 1999 156 V6 Q-auto
            2001 156 V6 (sadly cremated)

bazzbazz

On The Spot Alfa
Mobile Alfa Romeo Diagnostic/Repair/Maintenance/Service
Brisbane/Gold Coast
0405721613
onthespotalfa@iinet.net.au

bteoh

Someone trying to lock the camshaft without proper cam locks during a previous change?

bazzbazz

Close, but no cigar.  ;)
On The Spot Alfa
Mobile Alfa Romeo Diagnostic/Repair/Maintenance/Service
Brisbane/Gold Coast
0405721613
onthespotalfa@iinet.net.au

poohbah

Someone tried to remove the pulleys with some kind of locking jaw pliers?
Now:    2002 156 GTA
            1981 GTV
Before: 1999 156 V6 Q-auto
            2001 156 V6 (sadly cremated)

bazzbazz

#6
Close enough.

A colleague surmised that who previously worked on the car broke the taper locks by sticking a long chisel into the holes of the pulleys and
using a heavy hammer, thus leaving bite marks from the chisel.

You have to remember when this would have been done the orientation of the pulley would have been different.

As I have said before, the thing I hate more than anything else, is working on Alfas that other people have f@cked with.

One must now wonder what other terrors await us further into the job.
On The Spot Alfa
Mobile Alfa Romeo Diagnostic/Repair/Maintenance/Service
Brisbane/Gold Coast
0405721613
onthespotalfa@iinet.net.au

johnl

#7
Here's a mystery;
Spare TS cylinder head taken from a running engine. On disassembly it is discovered that the front journal on the exhaust camshaft is badly scored. Investigation discovers that the camshaft bearing 'saddle' at the front of the engine does not quite align with the head (i.e. the 'saddle' which forms the upper half of BOTH front camshaft bearings).

With the camshafts not fitted, and with the front bearing 'saddle' fitted and tightened (and with pilot tubes correctly fitted), where the saddle meets the head casting at the inlet camshaft front bearing, a fingernail catches on an almost imperceptibly tiny 'step', both sides of the bearing. This is not good and not right, but it gets worse. At the exhaust camshaft front bearing, there is a much worse 'step' where the saddle meets the head casting, quite pronounced both sides of the bearing. The upper bearing semi circle is very obviously laterally offset from the lower half of the bearing, and to a differing degree at each front camshaft bearing.

This is obviously why the camshaft journal was scored. Refitting the camshaft and it's obviously a bit 'tight' in this bearing...

It seems for all the world like the bearing saddle was not 'line bored' with this particular cylinder head, but on some different head. I can't imagine how at some stage in it's existence the wrong saddle ended up fitted to the wrong head casting...

However it might have happened, an otherwise good cylinder head is junk only because of this bizzare problem, unless it is re-line bored, which I suspect might cost more than purchasing another good used head...

And, if this head has a bearing saddle from some other head, it may well be that some other head out there has the bearing saddle from this head...

Regards,
John.