Hydraulic Lash adjuster
#2
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My car seems to have a tapping sound with all cylinders. I am not sure if its the injectors or the hyd. rockers?
Good question!
Good question!
#3
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Hi Gents:
As these cars now age, one starts to see issues like these.
Tapping sounds are usually caused by hydraulic lifter problems and you can pinpoint that with a mechanic's stethoscope or a long screwdriver. Simply place the end on various points of the valve covers and put your ear on the end of the handle. You'll hear everything,....
This will also rule out noisy injectors (which rarely make a sound you can hear).
You guys did not indicate the mileage on your engines and this is a factor in determining what might be at fault. The hydraulic lash adjusters used in these engines have VERY small internal passages and not forgiving of extended oil drain intervals.
IMHO, Porsche's oil change recommendations are too far apart to ensure the long-term health of such parts, especially when used in city traffic and for short trips. If I owned one of these cars, I'd be changing my oil & filters at 3000 mile intervals.
As these cars now age, one starts to see issues like these.
Tapping sounds are usually caused by hydraulic lifter problems and you can pinpoint that with a mechanic's stethoscope or a long screwdriver. Simply place the end on various points of the valve covers and put your ear on the end of the handle. You'll hear everything,....
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
This will also rule out noisy injectors (which rarely make a sound you can hear).
You guys did not indicate the mileage on your engines and this is a factor in determining what might be at fault. The hydraulic lash adjusters used in these engines have VERY small internal passages and not forgiving of extended oil drain intervals.
IMHO, Porsche's oil change recommendations are too far apart to ensure the long-term health of such parts, especially when used in city traffic and for short trips. If I owned one of these cars, I'd be changing my oil & filters at 3000 mile intervals.
#4
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Thanks for the reply Steve. My car has 42k on her. Frequently maintained before I owned it, and obsesively treated like a king ever since then. I dont hear one particular rocker, just a general faint clatter, like many other 993's I hear. Being hydraulic, I would imagine them being more quiet?
#5
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thanks Steve,
my cars barely got 10,000 km since ruf rebuilt it. i feel inclined to believe that the lash adjuster is not filling up hence the dry knocking of the valve during idle... its so bad i'm certain i can pinpoint it without the need for a sophisticated diagnosis.
my car puts out about 550 or so hp... hence my concern if the valve drops after damage then my potential damage is huge
97 993 TT
CTR2
my cars barely got 10,000 km since ruf rebuilt it. i feel inclined to believe that the lash adjuster is not filling up hence the dry knocking of the valve during idle... its so bad i'm certain i can pinpoint it without the need for a sophisticated diagnosis.
my car puts out about 550 or so hp... hence my concern if the valve drops after damage then my potential damage is huge
97 993 TT
CTR2