Click on a thumbnail to see the full-size image
Ford 2.0L engines are prone to valve seat failures. Aftermarket fix for these problems?
Okay, so Ford 2.0L engines are prone to valve seat failures. Isn’t there an aftermarket fix for these problems?
The article in the September issue of Engine Builder on rebuilding the Ford 2.0L SOHC engines struck a nerve with some people, who recalled an AERA Technical Bulletin covering valve seat breakage on 1997-2001 Ford 2.0L VIN P engines. Damage typically occurs originally at the number one cylinder intake seat. This information was published last September in our magazine.
Repeat engine failure has been reported shortly after starting repaired engines that had previously failed due to valve seat breakage in this area. Subsequent engine failures have been caused by debris that was left in either the intake or exhaust manifold. The debris included particles of valve seats, pistons and rings from the original failure.
Whenever a cylinder head is serviced it is common procedure for the technician to just move the intake and exhaust manifolds back to provide just enough room to get the cylinder head off of the engine. This procedure does not allow thorough cleaning of either manifold. When a valve seat comes out of its counter-bore and shatters into many pieces, normal air turbulence may cause pieces from the valve seat to enter either the intake or exhaust manifolds. The cylinder head for this engine originally used powder metal valve seats with an approximate depth of .286˝ (7.264 mm) that, when shattered, results in many pieces/debris.
For the reasons outlined above, it is necessary to remove both manifolds from the engine compartment and clean them. Failure to clean out the intake and exhaust manifolds may cause a repeat engine failure.
One manufacturer of aftermarket powder metal valve seat inserts has found that using different seat materials, processes and designs in order to improve seat retention in the cylinder head as well as a patented additional tempering process can eliminate the brittleness commonly found in PM valve seats (intake p/n 31909; exhaust p/n
31910). These seats also have additional seat depth and a reduced leading edge chamfer, features that provide increased seat-to-cylinder head contact area for better heat transfer. Inadequate heat transfer is thought to be a factor in OEM seat failures.
Once new seat inserts have been installed, they should be machined as shown in Figures 1-2, at 45° with a .069˝-.091˝ (1.75-2.32 mm) width and a maximum seat run-out of .0025˝ (.064 mm).
For information on receiving all of AERA’s regular monthly technical bulletins, call toll free 888-326-2372 or e-mail firstname.lastname@example.org.