Rupunzell
Bernice Loui
Damage free removal requires using a disc with a step and a puller set up.
The ID of the disc is slightly smaller than the OD of the aux shaft bearing journal surface, the OD of the disc is slightly smaller than the OD of the bearing. The disc has a threaded hole which allows a threaded rod to be used to provide force to remove or install the bearing. The disc also must be thin enough to fit and clear the gap in the block's aux shaft housing area. Two different size disc are required as the two bearing journal sizes are different.
Here is what the Fiat OEM bearing removal / install tool looks like. If time permits, I'll dig up the disc made some time ago to remove / install the aux shaft bearings for a few pictures. Using make-shift tool, socket or similar runs a very high risk of damaging the bearings during install or removal.
The Fiat aux shaft bearing reamer looks like this. It is a piloted reamer or guided reamer to assure proper alignment during the sizing operation and note it is always done with the bearings installed in the block to account for bearing crush post installation.
There are old school engine machinist who knows how to properly hone bearings to size. This was common in more than a few older engine designs. If you can find a shop like this, have them hone these bearings to size.
This is the aux bearing tool in use as shown in the Fiat factory service manual. I prefer using constant force over pounding as there is better control and has lower risk of damage to the bearings.
Fiat factory service manual pages on reaming the aux shaft bearings to fit.
Fiat specifications for aux bearing clearance and fit.
Proper bearing clearance is important as excessive clearance can and will affect oil pressure as it is the first feed from the oil pump after the oil filter.
*** Make sure the oil hole in the bearing is properly lined up with the oil hole in the block or assured destruction of the bearing / aux shaft will occur in short time.***
Bernice
The ID of the disc is slightly smaller than the OD of the aux shaft bearing journal surface, the OD of the disc is slightly smaller than the OD of the bearing. The disc has a threaded hole which allows a threaded rod to be used to provide force to remove or install the bearing. The disc also must be thin enough to fit and clear the gap in the block's aux shaft housing area. Two different size disc are required as the two bearing journal sizes are different.
Here is what the Fiat OEM bearing removal / install tool looks like. If time permits, I'll dig up the disc made some time ago to remove / install the aux shaft bearings for a few pictures. Using make-shift tool, socket or similar runs a very high risk of damaging the bearings during install or removal.
The Fiat aux shaft bearing reamer looks like this. It is a piloted reamer or guided reamer to assure proper alignment during the sizing operation and note it is always done with the bearings installed in the block to account for bearing crush post installation.
There are old school engine machinist who knows how to properly hone bearings to size. This was common in more than a few older engine designs. If you can find a shop like this, have them hone these bearings to size.
This is the aux bearing tool in use as shown in the Fiat factory service manual. I prefer using constant force over pounding as there is better control and has lower risk of damage to the bearings.
Fiat factory service manual pages on reaming the aux shaft bearings to fit.
Fiat specifications for aux bearing clearance and fit.
Proper bearing clearance is important as excessive clearance can and will affect oil pressure as it is the first feed from the oil pump after the oil filter.
*** Make sure the oil hole in the bearing is properly lined up with the oil hole in the block or assured destruction of the bearing / aux shaft will occur in short time.***
Bernice
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