Q. While working on a 2004 Mitsubishi 2.4L G69M engine, I got confused about the correct valve lash specs. Can you explain?
A. The AERA Technical Committee says Mitsubishi’s published information seems to have listed incomplete specifications as two different camshaft profiles were use. The following information regarding the correct valve lash specification and camshaft identification for 2004 Mitsubishi 2.4L SOHC, G69M engines may be helpful.
You must identify which camshaft is being used to obtain the correct valve lash specifications. To identify the cam, examine the slotted cam end and look for either a letter "L" or "G" as shown in Figure 1.
Lash adjustments can be slightly different for the two different cam profiles. The chart can be used once you’ve correctly identified which cam you have.
Q. Why did General Motors change the design of its timing chain on newer 2.2L VIN D and F engines?
A. According to the AERA Technical Committee, this change was implemented to improve oiling of the timing chains for 2000-2003 GM 2.2L VIN D & F engines
The models affected include the 2000-2003 Saturn L-Series with 2.2L engine (VIN F – RPO L61); the 2002-2003 Saturn VUE with 2.2L Engine (VIN D – RPO L61) and 2003 Saturn ION Vehicles
Design changes have been made to both the timing chain and timin chain oiling nozzle, requiring new service procedures as well. All GM timing chain kits now in service include the oiler nozzle.
This new nozzle has higher flow rate characteristics that will increase oil flow to the timing chain under low RPM operating conditions. Whenever replacing a timing chain, it is important to replace the oiler nozzle.
Previous service manuals for these vehicles refer to the timing chain index links being colored "silver" and "copper." With the implementation of the newer design chain and oiler assembly, the index link colors have changed. In order to avoid confusion, the service procedure text has been modified to refer to the index links as two common colored and one unique colored link.
Q. My installer customers have been getting complaints of cold-start engine noises on Subaru engines. Is it a symtom of failed engine bearings?
A. Subaru says a cold engine noise on 1999-2000 Subaru 2.2L and 2.5L engines sounds like it comes from the front of the engine and could be mistaken for failed bearings. This noise is heard after a cold start and will gradually go away as the engine warms up. It may therefore be difficult to reproduce unless the vehicle is left overnight.
It has been found that the timing belt tensioner on these vehicles may be weak allowing the timing belt to move and hit the inside of the timing belt cover. The bearing itself could also be at fault. So you must listen to the actual noise when the engine is cold before reaching a diagnosis conclusion.
If you suspect the belt tensioner, remove the front cover and look for evidence of rubbing or chafing. Also note that once removed, the timing belt tensioner feels fine, which is normal and cannot be compared to a NEW component.
