Discussion
I cant decide if the car runs better when its used every day. Probably just some psychological thing. I do get some chatter when firing up cold first thing which soon clears. I think some people believe this is the chains - I'm straying out of my knowledgeable area here. The tappet clicking noise I sometimes get has not presented itself for at least a week. I do make a point of keeping the revs up so using 3rd at 30 instead of 4th etc. If I am stationary for a while at idle I do regular childish throttle blips to get the oil moving around too. I've not had chance to use the car in anger as I'm just commuting but occasionally on a round about or just turning left or right at junctions I think I can feel when the car tips over enough for the tyres to lay flat and counter the negative camber - if that make sense. It seems to find extra grip as I tip the car over. Or maybe its just the natural 996 suspension doing its thing. I read on PPBB's thread that the rear suspension on these cars will toe in under compression.
I'm determined to make a decision on seats soon. I've been a bit distracted rebuilding my 3 wheel 981. I might just buy some black 997 seats or even blue just to try them out. I dont think I need sports seats so even vanilla 997 seats might be an improvement.
I'm determined to make a decision on seats soon. I've been a bit distracted rebuilding my 3 wheel 981. I might just buy some black 997 seats or even blue just to try them out. I dont think I need sports seats so even vanilla 997 seats might be an improvement.
Glasgow 911SC said:
ATM said:
I do get some chatter when firing up cold first thing which soon clears. I think some people believe this is the chains - I'm straying out of my knowledgeable area here.
Wouldn't the tensioners and guides etc have been swap during the rebuild?I might get a cold start video to demonstrate. When I was selling this car one of the interested parties asked me for a cold start sound clip. He then immediately started claiming the noises were not good. So ever since I've been suspicious. It could of been a negotiating tactic. I have no idea what is good, bad or normal.
ATM said:
Glasgow 911SC said:
ATM said:
I do get some chatter when firing up cold first thing which soon clears. I think some people believe this is the chains - I'm straying out of my knowledgeable area here.
Wouldn't the tensioners and guides etc have been swap during the rebuild?I might get a cold start video to demonstrate. When I was selling this car one of the interested parties asked me for a cold start sound clip. He then immediately started claiming the noises were not good. So ever since I've been suspicious. It could of been a negotiating tactic. I have no idea what is good, bad or normal.
Cheers.
ATM said:
If we believe the seller description which I copy pasted on page 1. There are a bunch of receipts from the rebuild for gaskets, bolts and clips etc. I didn't see anything about chains or guides or even the second hand head itself. Are these parts cheap to buy?
I might get a cold start video to demonstrate. When I was selling this car one of the interested parties asked me for a cold start sound clip. He then immediately started claiming the noises were not good. So ever since I've been suspicious. It could of been a negotiating tactic. I have no idea what is good, bad or normal.
Im sure the previous owner changed guides during the rebuild. They are obviously worn after 60k.I might get a cold start video to demonstrate. When I was selling this car one of the interested parties asked me for a cold start sound clip. He then immediately started claiming the noises were not good. So ever since I've been suspicious. It could of been a negotiating tactic. I have no idea what is good, bad or normal.
Any 996/986 I drove in the past made some strange noises starting cold. These engines are quite noisy until warm-up.
I admire your PH efforts though, running and DIY fixing two porks at once
I would have sold bought and get a semi decent 993 C4 instead. Loads of DIY capacity and fun to work at least...
ooid said:
Im sure the previous owner changed guides during the rebuild. They are obviously worn after 60k.
Any 996/986 I drove in the past made some strange noises starting cold. These engines are quite noisy until warm-up.
I admire your PH efforts though, running and DIY fixing two porks at once
I would have sold bought and get a semi decent 993 C4 instead. Loads of DIY capacity and fun to work at least...
The 993 does nothing for me. I could get excited about a 964 but the price difference over a 996 makes me think there is no point. I've not done much DIY on the 996. But I might in the future we'll see. Any 996/986 I drove in the past made some strange noises starting cold. These engines are quite noisy until warm-up.
I admire your PH efforts though, running and DIY fixing two porks at once
I would have sold bought and get a semi decent 993 C4 instead. Loads of DIY capacity and fun to work at least...
ATM said:
If we believe the seller description which I copy pasted on page 1. There are a bunch of receipts from the rebuild for gaskets, bolts and clips etc. I didn't see anything about chains or guides or even the second hand head itself. Are these parts cheap to buy?
I might get a cold start video to demonstrate. When I was selling this car one of the interested parties asked me for a cold start sound clip. He then immediately started claiming the noises were not good. So ever since I've been suspicious. It could of been a negotiating tactic. I have no idea what is good, bad or normal.
No, nothing with a Porsche part number stamped on it is cheap. Incidentally the tappets are an INA part and much cheaper to buy from BMW.I might get a cold start video to demonstrate. When I was selling this car one of the interested parties asked me for a cold start sound clip. He then immediately started claiming the noises were not good. So ever since I've been suspicious. It could of been a negotiating tactic. I have no idea what is good, bad or normal.
Any M96 with a few miles on it clatters on cold start.
The chain tensioners were not spring loaded on these, so need oil pressure to work. Therefore you get some timing chain rattle for the first second or so. As they get used, tolerances increase and this noise takes longer to go away.
The tensioner pads which act on the chain do wear, they start flat and quickly wear two grooves in them from the chain and then go on for a long long long time. I don't think I've seen a pic of one worn out. You might occasionally see bits of darkened plastic in the oil filter, this is from the tensioner pads. No need to change them IMO unless the engine is open for other work / new chains.
You will likely have the tap tap tap of a tappet or two when cold, again they ALL do this with some miles on and is not worth opening the engine for. This will go away when warmed up.
A heavier weight oil will help with both of those, some run 10w40, some run 10w50. I use a millers 10w40 and it quietened cold start down a lot.
These are raw, noisy engines - much rawer than the 3.6 or subsequent engines. You will find the idle is not as smooth as a 3.6 - do not compare the noises your 3.4 makes to other cars.....
ATM said:
When I was selling this car one of the interested parties asked me for a cold start sound clip. He then immediately started claiming the noises were not good. So ever since I've been suspicious. It could of been a negotiating tactic. I have no idea what is good, bad or normal.
It's a tactic, or an armchair expert.If something was 'not good' it would have fallen apart by now - you've owned it for a decent time. As the others have said, they all tap tap a little when stone cold - mine briefly exhibits heavy chain rustle for 1/4 of a second after a start where the engine has stood for more than a week whilst the tensioners pump up. It then has a light tapping sound from a few lifters for a few minutes, seconds if the revs are lifted to 1300 or so for 30 seconds.
The cam chain (and IMS) are spring loaded on early engines (its internal) and that assists the tension but the majority of the tension is applied by oil pressure, and the design of the tensioners aren't great so the oil bleeds out when the engine is stopped for any length of time. The later IMS tensioner has a whacking great spring on the outside of it, but the main difference is the change to a morse type chain which is quieter than a roller chain (if less capable of transmitting as much load but in this setting isn't an issue).
If it's any reassurance, even the legendary Mezger in the Mk1 996 GT3 does it. Google Mk1 996 GT3 startup "death rattle"...
The Mezger in the GT3 gets worked hard, and the chains and chain guides wear. The noise on start up can be pretty bad, and it can last 3-5 seconds, then disappears. On the first example I owned, we installed a cutout for the fuel pump and ignition on the centre console. You switched this "on" (and the power to the fuel pump and ignition off in the process) then turned the engine over until the oil pressure gauge started to show pressure. On a bad day you could hear the source of the rattle, albeit it was very light and very quiet.
I was staggered how long it took to get oil pressure showing on the gauge, often 20 seconds or more of cranking (this on a hard used 65k mile engine).
Once the oil pressure was showing, stop cranking, flick the switch for the fuel and ignition "off" and start the engine. It was always whisper quiet when started in this manner.
See it been done with a far more exotic and expensive engine here :
https://www.youtube.com/watch?v=wcS48NX9YuA
The Mezger in the GT3 gets worked hard, and the chains and chain guides wear. The noise on start up can be pretty bad, and it can last 3-5 seconds, then disappears. On the first example I owned, we installed a cutout for the fuel pump and ignition on the centre console. You switched this "on" (and the power to the fuel pump and ignition off in the process) then turned the engine over until the oil pressure gauge started to show pressure. On a bad day you could hear the source of the rattle, albeit it was very light and very quiet.
I was staggered how long it took to get oil pressure showing on the gauge, often 20 seconds or more of cranking (this on a hard used 65k mile engine).
Once the oil pressure was showing, stop cranking, flick the switch for the fuel and ignition "off" and start the engine. It was always whisper quiet when started in this manner.
See it been done with a far more exotic and expensive engine here :
https://www.youtube.com/watch?v=wcS48NX9YuA
was8v said:
ATM said:
Got some of the under body plastics hanging down and quite badly ground away. Pic is a bit rubbish.
Theres a small bit of undertray like that on each side, in front of each tyre.One of mine fell off too in the floods, scored the replacement on ebay.
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