3.2 owners- how loud are your valves?

tdorsey835 · 08-10-2003, 01:09 PM

When driving with the windows down, sunroof open and radio off, I can hear my valves making a tapping sound between 1,500 and 2,500 rpms. I can also hear them tapping at idle from outside the car. The car runs very well, and uses little oil and rarely smokes. (only sometimes on start up after sitting) The car is completely stock with 157k miles. The previous Owner had a proffessional valve adjustment done at 153k miles. I have all records since 122k miles with no record of valve guide replacement or any other engine rebuild work.

What kind of noise do your valves make? Is this normal? Or am I looking at a top end rebuild soon? How about anyone that has heard them before and after a rebuild. Thanks for your input.

350HP930 · 08-10-2003, 01:13 PM

The engine should usually sound like a sewing machine running at full tilt without any noticable tapping or ticking.

If you have tapping its usually one or more of the following problems.

Needs Valve Adjustment
Bad Valve Guides
Bad Rocker Arm And/Or Cam Lobe
Broken Valve Spring

08-10-2003, 01:21 PM

I can sometimes hear mine tapping too. Same goes for my friend's 1988.

We both have no smoke, almost no oil consumption, perfect running engines and normal performance. Both cars have had a pro valve adjustment done recently. Both are about 100000 miles.

We're both paranoid about our 911s so maybe we're making things worse than they are? My mechanic says: relax it's no big deal.

350HP930 · 08-10-2003, 01:35 PM

Yeah, when valve guides get old and sloppy they may get a little noisy but its usually nothing more than an annoyance.

Stuttgart951 · 08-10-2003, 04:25 PM

I can hear my valves as well - but Ive been able to hear the valves on just about every 911 engine built before 1995.

Paul Franssen · Paul Franssen's Garage

Quote:

Originally posted by Mikkel
I can sometimes hear mine tapping too. Same goes for my friend's 1988.

We both have no smoke, almost no oil consumption, perfect running engines and normal performance. Both cars have had a pro valve adjustment done recently. Both are about 100000 miles.

We're both paranoid about our 911s so maybe we're making things worse than they are? My mechanic says: relax it's no big deal.

I've got a 1988. All of the above observations more or less apply to my car, which has 127000 miles (203000 km). When I first went to my present wrench, he immediately said "you need your valves set". He did. The noise was the same. He told me not to worry about it.

My valves make a ticking sound upon idling. Sometimes the ticking goes mostly away for a short while, only to come back after a few seconds, and so on (related to the valve rotating around the seat?). I once heard another 3.2 liter Carrera without any ticking: utter smoothness. My guess is his valves were too tight!

Bill Verburg · Bill Verburg's Garage

Quote:

Originally posted by 350HP930
The engine should usually sound like a sewing machine running at full tilt without any noticable tapping or ticking.

If you have tapping its usually one or more of the following problems.

Needs Valve Adjustment
Bad Valve Guides
Bad Rocker Arm And/Or Cam Lobe
Broken Valve Spring

I agree w/ this statement. On a new or newly rebuilt engine the chains on gears will be the loudest mechanical noise.

PeteBrown · 08-11-2003, 07:14 AM

My '87 has 68,000 miles on it and the valves were profesionally adjusted at 62,000. I can hear a tapping at idle and between 2-3K rpm. I asked my mechanic to listen to it and he said all was fine. Some of the tapping noise is reportedly from the injectors turning on and off.

yelcab1 · 08-11-2003, 08:08 AM

I have never been able to totall got rid of the valve train noise for the 9 years that I had my 84 carrera. It sounded like ta sewing machine for the first 10 minutes, then after it has warmed up, it sounds like clapping noise. Valve job with new valve guides and rocker arms did not help. So, in the end, I got rid of the valve noise by getting rid of the car.

My brother 1985 Turbo Look Carrera sounded like a sewing machine all day long.

350HP930 · 08-11-2003, 08:33 AM

Quote:

Originally posted by Paul Franssen
My valves make a ticking sound upon idling. Sometimes the ticking goes mostly away for a short while, only to come back after a few seconds, and so on (related to the valve rotating around the seat?).

Bingo, its either that or its the direction the end of the valve stem shifts when actuated by the rocker.

When I adjusted my valves around the 80K mile mark only a couple valves were a little tight.

Several thousand miles after the adjustment I too got my first case of intermittent ticking.

Though I only had several porsche valve adjustments under my belt at that time I had done hundreds of valve adjustments on other cars and motorcycles so I knew that either my adjustment was off or my valve guides were getting sloppy.

I took everything apart again and discovered that the lash adjustment was still perfect so I realized I would just have to live with it till I got around to rebuilding the heads.

It was at that point that I started going easier on my motor since I knew that the exhaust valves were less likely to bleed off heat if their guides were getting sloppy.

tdorsey835 · 08-11-2003, 08:39 AM

Ok so bottom line... if I've got a ticking sound and it definitely is the valves, is there anything to worry about given I've got no other sypmtoms of a worn engine? By the way, regarding the sewing machine reference... I can't hear in my head what a well tuned sewing maching sounds like, but I assume it does not include any ticking? Wayne, your'e the engine building guru, what's your opnion on valve noise?