I'm about 1900 miles in the ARX cleaning phase and my lifters started making a very loud noise when cold. The noise does really comes from the hydraulic lifters and occurs at every cold start now, but the noise dissappears in about 1-2min after startup.
Now I'm a bit surprised because I've read testimonials that ARX actually did quiet down noisy lifters. In my case it sounds like the opposite... The only thing I changed is ARX. I use the same oil as before the cleaning (Mobil Super S 10w40). Last winter the car sat outside at temp around -5°C with that oil. It did slightly make noise when cold but clearly not as much as now with ARX (and now the outside temp is about +15°C). I will move anyway to a 5w40 for the rinse phase and after but I'm just a bit worried about this loud tappet noise when cold. To me it would mean that actually ARX did thicken the oil up.....or that it removed sludge around the valve seals that was keeping some of the oil flowing down to the sump after a drive (probably not likely but). Is it safe to go one with the clean phase or should I drain and start the rinse phase now to stop this tappet noise?
What else may explain ARX makes my lifters so noisy now?
Thanks
Car is a 1997 Volvo S40 2.0L petrol (atmospheric engine) with 200K miles
Relax. There may be more noises coming into the picture as you move on. Not everything is clogged to the same degree, nor does it clean up in a balanced manner.
It's like diesel injectors that leak down as the engine ages, but the timing chain stretches at the same time. The injector timing appears normal until you service the injectors and find out that you need to advance your pump (old Peugeot).
Right now your drain capacity exceeds your supply capacity at certain times. It will take some time to restore the supply passage to full balanced flow.
This is the clearest indication that there was indeed clogged arteries and that they are being reopened to full utility.
It can make you nervous if you're not prepared.
Change the filter if you need something proactive to do in the meantime.
-- Edited by geeaea on Tuesday 29th of September 2009 06:28:18 AM
No. Change the filter now and continue on. Some engines are "noise critical" in terms of filters. It's not common, but possible. A filter in most engines can be heavily loaded and not cause lifter noise. The filter, in most cases, under most conditions is invisible. Euro engines, some anyway, run higher pressures and have higher bypass valve settings. They do this (on something like a Porsche/Audi/etc) since the engine oil pump may be in relief for the entire driving event. That is the pressure may be regulated to 80-100psi, but the typical pressure before oil warm up may be 125-135 (nearly 10bars). So they have higher bypass valve settings to force more oil through the filter. If they didn't, the entire life of the engine may not filter very much oil. The filter would have the bypass open 24/7/365.
This is just an example of how a filter may alter some flow. It's not normally an issue, but worth it if it brings you peace of mind.
