'69 C3-4sp L48 (crate) w/15k miles
To remedy an oil leak I must replace a cracked plastic timing chain cover.
When I torque-down the fasteners on a new bolt-compatible Chineseum metal replacement cover, the thin-gauge flanges bow-out between bolt heads. Exact same thing happened when I torque-down the fasteners on another new bolt-compatible Chineseum metal replacement cover. Obviously this is unacceptable.
The flange on the old plastic cover I removed from this engine was comparatively thick. And most significant, I recall that the plastic flange sat flush to the mated surface with no gaps or oil seepage. Must I purchase a plastic replacement timing chain cover..? This likelihood bothers me. It seems only Holley makes a robust (meaning: thick) metal timing chain cover... though at a Holley price, of course.
Oil pans are often braced by a strip of metal between the flange and the fasteners on either side of the pan to distribute clamping force in order to prevent flange bowing/warping. This is exactly what I need to clamp a metal timing chain cover to the engine. But unless I whip up a model in SolidWorks and send off an order to Shapeways, no such widget exists.
So what's the deal with flimsy metal timing chain covers? The flanges must make a seal to prevent oil weep. That requires a compressible gasket mashed between paired surfaces with sufficient clampy goodness. Arching metal between fasteners along the perimeter of the flange defeats this function.
I should be driving this car presently. Instead, it remains on stands while I try to find a viable solution to this frustrating problem.
To remedy an oil leak I must replace a cracked plastic timing chain cover.
When I torque-down the fasteners on a new bolt-compatible Chineseum metal replacement cover, the thin-gauge flanges bow-out between bolt heads. Exact same thing happened when I torque-down the fasteners on another new bolt-compatible Chineseum metal replacement cover. Obviously this is unacceptable.
The flange on the old plastic cover I removed from this engine was comparatively thick. And most significant, I recall that the plastic flange sat flush to the mated surface with no gaps or oil seepage. Must I purchase a plastic replacement timing chain cover..? This likelihood bothers me. It seems only Holley makes a robust (meaning: thick) metal timing chain cover... though at a Holley price, of course.
Oil pans are often braced by a strip of metal between the flange and the fasteners on either side of the pan to distribute clamping force in order to prevent flange bowing/warping. This is exactly what I need to clamp a metal timing chain cover to the engine. But unless I whip up a model in SolidWorks and send off an order to Shapeways, no such widget exists.
So what's the deal with flimsy metal timing chain covers? The flanges must make a seal to prevent oil weep. That requires a compressible gasket mashed between paired surfaces with sufficient clampy goodness. Arching metal between fasteners along the perimeter of the flange defeats this function.
I should be driving this car presently. Instead, it remains on stands while I try to find a viable solution to this frustrating problem.
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