If a lifter failed in a 2001 Mack truck, how concerned should I be about the rest of the components?
If valve lifter failure is experienced on Mack MIDR 06.02.12 or MIDR 06.02.26 diesel engines with original style lifters, the AERA Technical Committee recommends that all 12 lifters and pushrods be replaced with improved components.
An improved valve lifter (p/n 4103-5010258903 which replaces p/n 4103-5000592104) and pushrod (p/n 4103-5010450813 which replaces p/n 4103-5000133273) arrangement for Mack Mid-Liner MIDR 06.02.12 and MIDR 06.02.26 engine have been released and are available only through the Mack parts system.
The new lifter has a lower pivot point, which reduces side loading and increases lifter durability. Because of the lower pivot point, new pushrods are approximately one inch (25.4 mm) longer than the previous design pushrods.
Beginning April 1, 2001 the improved valve lifters were implemented into production of MIDR 06.02.12 and MIDR 06.02.26 short blocks. However, new pushrods are not supplied with the short block assemblies. When replacing an existing engine with a new short block manufactured after April 1, 2001, it will be necessary to use longer pushrods.
Note: These same valve lifters and pushrods are used in the new dCi 6 Common Rail engine, which is used in the FREEDOM Chassis
Did Toyota change the timing belt tensioner spring for the Camry. Can I mix parts?
According to the AERA Technical Committee, the following information on a revised timing belt tensioner spring for 1992-96 Toyota 2.2L 5S-FE (Camry) engines should be considered any time the timing belt is removed from the engine.
The timing belt and tensioner spring for 5S-FE engines has been revised beginning with the 1997-year model. The timing belt and spring are designed for use AS A SET, and one should not be replaced without replacing the other. All 1992-96 engines should be updated with the revised spring and belt AS A SET for improved durability. Intermixing prior and revised components should not be attempted as improper tension and alignment may occur.
Its 4mm shorter length and additional 3 coils can identify the revised spring. New tension spring p/n 90507-17003 replaces p/n 90507-18030. New timing belt p/n 3568-09041 replaces p/n 13568-09040.
Is it true the Ford 4.6L engine may have used two different crankshafts?
Yes, all of the Romeo engines came with a six-bolt flange, but some of the Windsors came with crankshafts with eight-bolt flanges instead.