Do a search of the web for a hydraulic valve picture. Then you will understand what causes the ticking.

 

1999,

Actually lifter noise occurs when the hydraulic lifters aren't completely "pumped up" to occupy all the space between the cam and the valve. You can only hear this when the car is running because the noise is from the lifter/valvetrain tapping as a result of the space. Oil that is too thick or dirty lifters are the most common cause of this valve noise. Actually, running a lighter weight oil will help this condition because it results in more rapid and complete "pumping up" of the hydraulic valves.

I believe the ticking noise that you are referring to is simply the hot exhaust cooling off.

Tonger

 

Just the opposite is true. On a hot engine, the oil (Mobil Water) is so thin that more of it bleeds out of the lifter, eliminating the hydraulic lift in it. This causes slack to the cam which causes a ticking sound. A less thin oil will not bleed out of the lifters as much.

NOTE: Does ANYONE really confuse heat ticking of the exhaust to valve ticking?

 

What were your oil temperatures like before you installed the supercharger?

 

My water and oil temps are not effected by the SC. A few minor mods actually resulted in both temperatures running less that when delivered by Porsche.

 

what kind of mods did you do to get a lower temp?

 

I'm going to guess a lower temp thermostat is all it would take, that any maybe an aux fan switch.

 

Lower your coolant mix to 40% antifreeze and install manual front fan and engine compartment fan switches (or lower temperature sensor) and your car will run as cool driving it hard around town as it does running at 80 mph on the highway. Stock thermostat as even removing the thermostat will not decrease coolant temp.

 

1999, I just put in 15w50. No ticking sound in normal driving. But when I came off the track the other day the ticking sound was really really loud. It sounded like an old 993! As it cooled off the sound went away. Something to worry about?

 

Curious about engine wear from the different weight oils? Blackstone test it. I am sending my Blackstone oil test this week sometime.

My friend who did the test on his 996 with Mobil 0w40 came out with flying colors, no abnormal wear. This is with many AXs with a DE thrown in on top of DD.

 

I get a clatter for about 2 minutes with 5w 50 ( In Australia)

 

Yes, as stated above too thick of an oil will not keep the lifters filled. I run the water down here in TX and guess what....no ticking...ever, and last time I checked it gets real hot down here too

 

I've posted my lab results with mobil 1 15w50 before, here's a a brief clip from my sample that was in service for over 1 yr (I don't put alot of miles on the car:
"All wear read at or below averages for this type of engine, which is a very good indication of normal wearing parts and careful operation. The universal averages show normal wear after 4800 miles on the oil. Insolubles were low
at 0.2%, showing good oil filtration. No fuel dilution or anti-freeze was found. Silicon was normal indicating good air filtration. The TBN was 7.4, loads of active additive left. Try 4000 miles for your next sample. Leaving it in place more than a year is okay."

side note: I'm currently trying the Amsoil Euro 5w40 this time.

Andrew

 

How hot is your engine running? The change to 15W50 would not be the cause of increased valve noise (if that is what you are hearing). Porsche themselves approve 5W50 and so even those who do not have a brain of their own and only follow Porsche's guidance can't pin this on the 15W50 as it is the same viscosity of 5W50 at track temperatures.

Make sure that the noise is in fact valves and not just the egr valve which can make a hell of a noise when the engine is run hard.

 

Ok let me try to understand. If your engine "ticks" and you are running one of Porsche recommended oils you should change to 15w50 right away to eliminate the "tick". If your engine "ticks" using 15w50 the noise is obviously from some problem that is not oil related.

Seems to me (if he were to employ your previous logic) he should try an even higher viscosity. Maybe some 25w70 is in order?

Someone should give it the good old college try......