Oil Pickup Blockage in Holden Alloytec V6
Author: ETP Engine Parts Date Posted:7 December 2019
Like most most modern engines, the Alloytec V6 has been known for it's ability to turn oil into sludge. When this occurs, it can cause irrepairable damage to an engine. In this example, a customer had a VZ Commodore which would not start one morning.
The first step in the diagnosis was to check all the fault codes, of which there were none, then check the ignition and fuel, both of which were ok. A quick compression test then showed that the engine had no compression, which clearly was an issue.
Removal of the rocker covers and timing cover is then done to check the timing of the valves as well as the timing chain and guides. In this case, the timing chain and guides were excessively worn out, so much so that the cam timing had jumped six teeth! Clearly this engine was out of timing.
The primary chain guide and tensioner were also worn down to metal, with the tensioner completely extended. Pretty common for these engines, particularly given their configuration and mileage, so it's safe to assume that this was the problem.
When inspecting the cylinder heads and timing cover, there was an extreme amount of oil sludge. To further diagnose the issue, it was decided that sump removal was the best plan. If the pickup is blocked there can be a problem.
And in this case, the pickup was completely blocked due to oil sludge. If the pickup had not been inspected as part of this repair, there would have been an entire engine failure shortly after the repair of the timing chain.
In the case of the VZ Commodore ( and other models ) it is possible to remove the sump without needing to remove the engine or the K frame. Here is how to:
Check This Guide on How to Remove The Engine or the K Frame
- Remove the two bolts securing the power steering lines to K Frame cross brace.
- Remove the one bolt securing the auto transmission cooler pipes to RHF of K Frame.
- Remove both of the engine mount nuts from under the vehicle.
- Remove the two sway bar mounting bolts and move the power steering rack backwards.
- Jack up the engine under bell housing (use a wooden block) slowly until it touches firewall.
- Remove the sump bolts and pick up sliding it between the block and the K Frame.
- This saves a lot of time and no exhaust pipes, fuel lines, radiator hoses etc. need to be removed to do this!
It's not uncommon for modern engines to turn oil into sludge. As soon as you get this, you then see wearing of timing chains, which in this case the Commodore is famous for. The recommended interval for oil change is 15,000kms, but given that these engines are getting older, it could be worthwhile doing it much more frequently to prolong the life of the engine.
Similarly, with the Alloytec V6, they do not have a low oil pressure warning light. There is a sensor that goes to the ECM, which then can log the code and send a message to the dashboard, but in this case that hadn't happened. There was no codes on display or no messages shown on the dash.
To solve this problem, the oil pickup and sump were cleaned and refitted. Along with an entirely new timing kit and a pair of reconditioned cylinder heads, the vehicle is now good as new.
The key here is the oil change interval. It's always important to encourage your customers to increase the frequency of their oil changes, and then on each change or with any major service, check the oil pickup to ensure that it's clean with no sludge.
And of course, if you need the replacement parts, come and see us at ETP Online.