1964-67 Cadillac 429 (and 1963, 390) front engine covers

[Scot Minesinger]

As you have read, just replaced a timing chain on a 1965 Cadillac 429 engine and am cleaning it back up to put it all back together again.  How do I know if the aluminum front cover is bad?  This one seems good.  What is the common point of failure?

I have it all cleaned up and about ready to spray it before re-assembly.

[cadillactim]

Scott

Electrolysis is a common problem, especially around the coolant passages. Look for parts of the aluminum to be
damaged from it. The oil pump walls and bottom plate can have tiny scratches you can feel with your fingernails, but big scratches and gouges will affect oil pressure.

Make sure the replacement gaskets on the oil pump are paper thin. The thicker gaskets will reduce oil pressure, as they create more clearance, thus lowering pressure.

Tim

[russ austin]

The shop manual gives inspection criteria for the oil pump. The hole where the oil pump gear shaft goes through wears, allowing the gear to rub onto the wall of the oil pump cavity.

[TJ Hopland]

Oil pump is always the reason I heard about.   Buick had the same design and problem into the 80's.   At one time there were places that would do a sleeve insert in the Buicks,  seems like if it worked for them it would work on the 429's too. 

[savemy67]

Hello Scot,

As others have indicated, rotating steel parts in an aluminum casting could result in wear.  The 429 front covers house more than their fair share of accessories.

In addition to checking oil pump shaft and gear clearances, be sure to check every mounting surface for straightness with a known good straightedge and a feeler gauge.  If you want to be "sleep-at-night" sure, you could use a dye penetrant detection product on the cover to check for cracks in the aluminum.  This process is similar in concept to using a dye to check for leaks in the A/C system.  While the covers are not subject to the same stresses as blocks and heads, you don't know what the cover and attaching bolts have been subject to during the last 53 years.

Christopher Winter

[Scot Minesinger]

And I am good - thanks all.