On my ap2 2005, i have oil leak on my oil filter since the last 2 oil changes, with 2 differents filters, the leak start after 3000km after the oil change, the filter is tight, not to tight, all seem ok, no old gasket with the new, i found no leak on vtec solenoid, no leak except at the filter but after around 3000km, i lift the car and the oil filter have oil on it that drop to subframe. I found nothing on the forum and really dont know from where it come. A dealer told me that some Honda have the inside sleeve that goes in the center hole of the filter that was to screwed in the block and need to be unscrew to avoid the leak???? Anywone can help me?

 

Many times leaks start higher up and work their way down to the oil filter area and then drip off the filter. Double check around the valvecover gasket, the oil pressure sensor, and check the bottom of the vtec solenoid. Run your hand over all areas above the oil filter and see if you pick up any damp oil residue.

Secondly, are you installing the filters based on torque or the 7/8th turn requirement. Those are the only two proper ways to install an oil filter on these cars. Too tight or too loose will cause a leak. I assume you are using the proper sized PCX Honda filter ?.

Thirdly, there is a slim chance that the oil cooler mounting is causing the leak if the center bolt is loose. That is pretty rare and only usually happens if someone has removed or replaced it in the past. You need a really big socket to tighten the oil cooler center bolt, I haven't found one that works so I don't know what size it is. You could easily do it yourself if you know what size bolt that is, you need a deep socket as well as a large size, and a torque wrench. Maybe someone on here can tell us what size socket fits on the oil cooler center bolt, it's not listed in the service manual.

 

and to get the 7/8 turn you wont be able to do it by hand. that center bolt is pretty big. id guess a 25 or 23 is the size you are looking for. hopefully billman chimes in.

 

The boot of the switch, i think it was the oil pressure switch have oil inside, it is the oil pressure switch and do it only need to be retorque or replace?

 

That could the source of your leak, as it's in the right location to cause oil to hit the filter. I wonder if someone has performed an oil pressure test on that motor in the past ?.

See if you can snug it down hand-tight. I don't see a torque rating for the oil pressure switch, but I know it is a pretty small thread, and it's going into aluminum so be careful. I would just snug it down and see if it is loose, that might be enough to stop the leak. It's probably going to be around 7-10 ft lbs. torque, but just snug it down hand tight and don't force it too much. If it continues to leak you can remove it and use some thread sealant on the threads of the switch, but I would see if it can be tightened first.

You will need to remove the wire by unscrewing the small bolt that is in the head of the oil pressure switch, then see if the switch can be tightened down.

 

Agree with this^^

 

Nice, i change my switch, it lightly leak inside the boot and it resolve my Vtec hesitation that i have since 2 years! I adjust my valve at the same time, never adjust before (85000km), only 1 valves was ok and the others only .001 to loose but i can feel a big improve in power, very impressive since it was only lightly loose but i can really feel more power, very happy ;-)

 

thank you for coming back and posting your fix! glad you got it all sorted out.