Engine Oil Pressure
The Testing of a blocked oil pick up
Volkswagon Golf 2001, 1.6L AKL engine
The vehicle came in on a tow truck. when cranking the engine seemed to have no compression.
A quick test Showed the timing belt was not turning when the engine was cranked indicating that there was missing teeth on the timing belt.
After repair of the timing belt the vehicle was driven and the oil light was blinking.
Checked oil level and found 1 litre over full, Drained and retested. Oil light still blinked.
We removed the oil pressure switch and decided to give the engine a manual oil pressure test, the results were shocking. At start up the engine had 50 psi oil pressure and with only 1 minute of running the oil pressure had dropped to 30 psi, when the engine was revved the oil pressure became lower and lower, till the pressure almost become non-existent suggesting that the oil pump could not keep up with the supply of oil, by this time the engine was very rattly at the top suggesting that the lifters were not receiving any oil.
We had encountered this problem before with a blocked oil pick up strainer, we decided to drain the engine oil and remove the engine sump, once the engine sump was removed we found that the oil pick up was indeed blocked, After successful cleaning of the oil pick up strainer, we refitted the strainer back to the oil pump and refitted the engine sump.
We decided that it was best to refill the oil with a 15/40 Diesel oil, for the excellent cleaning properties of diesel oil. the oil filter was also changed.
The oil pressure was tested once again with a clean oil system, and the results spoke for them selves, upon first start up the and filling of the oil filter the engine was still rattly, but once the oil pressure began to rise on the oil pressure gauge the engine became smooth and quiet without hesitation.
The oil pressure at idle was at 55 Psi and when revved, the oil pressure rose to 75 psi, indicating that the oil control system was now working at optimum performance.
We later released, after putting 2 and 2 together that the timing belt had not failed due to age, but the timing belt had missing teeth due to the cam being tight in the cam tunnel, which caused the crank sprocket to eat away at the timing belt.
The customer was indeed lucky that the engine did not bend any valves and that we test drive every vehicle before giving the vehicle back, which enabled us to learn that the engine oil control system had an issue.
This issue with the vehicle is only due to lack of oil changes, which in P & G Motors opinion that log book service intervals are indeed to long and should be halved to keep the engine clean and in a healthy state.
The videos below show the working of the oil pressure before and after.