Over rev question and engine noise

[912UK]

Hello didn't think I would be posting in here.. But madness has engulfed me so I am out of my depth with all this watercooled stuff

Went to look at a 996 Turbo 80k lots of history all looked good on paper and then we plugged in the Porsche computer at a 996 watercool tec place and boom

Stage 2 over revs 200 hours ago with a rating of 420 now I was lead to understand this was very high reading and it amounted to 2% of the engine's running life. But now I have read more and also had a quick chat to some one in the know from a point of big named people.. the 420 is sparks eg work all this out and it's infact under 2 seconds at stage 2

being a Turbo they are meant to be much stronger and the chap I spoke to rightly said there is a lot of rubbish on the internet and fact is off the record alot of cars esp Turbo's would have gone into the red.

So the point is, is this a drama or not????????



Also there is a rattle coming from the N/S rear of the engine and when I say rattle it's only there because I can hear it as I am looking for noises it revs freely it drives nice a small list of to do issues. It's got the all important X50 pack

The rattle so I was told was coming from the gear that is on the cam that is secured in place by 3 woodruff keys and it's these keys that are worn and causing the rattle ( please do not think this rattle is heard from like 20 paces you have to have your head in the engine bay ! I may have OCD when a car is this much money ! I am a mear 912 owner you see )

So your views please. Thanks in advance. []

 

[vitesse]

If 3 woodruff keys are that badly hammered that they rattle,I would be seriously worried-anytime now one would expect the gear boss to fracture--& doesn't sound like Porsche type engineering-it would only happen were the bolt securing the gear onto the camshaft be loose.

It must be something else in my opinion.

 

[912UK]

I can understand that had it not been for the fact that the place that explained this to me

then took me to two engines in bits! one with it worn before rebuild and one that is now ready to be rebuilt and it's tight.

so you can see why I am questioning it if others have had this. Just it's alot of money to get it wrong.

 

[tscaptain]

Don't know about Woodruff keys but the over revs are insignificant.[]

 

[912UK]

do you know what, the more I am understanding the more i am thinking your could very well be correct.

As usual some info on the internet you read to help do your home work. Is infact floored, it goes viral and then it's folk law that

x is bad

y is even worse

and z is just go to jail!!

I have put in a call to the guys at Hartec and we will see what they say. There are other cars at the end of the day.

 

[tscaptain]

Having said that I have just checked and the 996 turbo only has range 1 and 2 over rev, unlike the later cars which go up to 5!

 

[Richard_Hamilton]

You are correct in your calculation - it is less than 1.4 seconds in the life of the car, which isn't much, even assuming it happened in a single event.

The bolts can also come loose on the intermediate shaft gear, which causes a rattle. Rare, but expensive to fix. Strangely, and maybe this is coincidence, I've only heard of this happening on cars which have been chipped. Has this one?

 

[912UK]

I have no idea if it has. it's an x50 pack so it's got enough ponies under the trunk but you never know some muppet might have thought it needed more. For the life of me I don't know why? Anything that's expensive to fix i am allergic to...... [&:]

 

[912UK]

Anyone live nr Gloucester?

Only there is a newer Turbo up there but abit out the price range. But they might want to sell it......

 

[richard hall]

ORIGINAL: Richard Hamilton

You are correct in your calculation - it is less than 1.4 seconds in the life of the car, which isn't much, even assuming it happened in a single event.

The bolts can also come loose on the intermediate shaft gear, which causes a rattle. Rare, but expensive to fix. Strangely, and maybe this is coincidence, I've only heard of this happening on cars which have been chipped. Has this one?

unfortunately that isnt true there are a lot of 2002 x50,s in the states that this happened to and hadnt been modified you are correct it happens to the x50 more than the standard turbo

as I alluded to most people thought it was just MY 2002 (source Kevin Ultimate motorwerks)but as I know only to well it also happened to my MY 2005

the truth is nobody really knows why but in essence it is really poor engineering on porsche's part to not use either schnorr washers or even locktight the bolts
the new replacement shaft and gear from Porsche didnt have locktighted bolts in fact Tony said they were not really tight at all!they are now F tight

ask yourself why does porsche use a solid billet shaft in the gt3 block

in general terms it really sticks in the throat when for the sake of £2 of washers on a £130,000 car an otherwise completly normal engine needs a rebuild

the bean counters really won out on that! and at the customers expense

a lot of people in the states (after repeated advice form Kevin ala UMW)have now resorted to oil analysis to catch this problem early

wrt to the original poster only you can make a judgement call on type 2 over revs the general sp was that after 150 operating time from the event you should be ok, ie it should have been long enough since the event that if the chains where going to go they would have done

however this issue has arisen more recently in posts on 997 turbo's the gist of which was that come resale time people might get sniffy there are so many good turbos out there unless this one is to die for I would look elsewhere

 

[924nutter]

I understood it had more to do with whether or not Porsche would extend the warranty. Iam sure that somewhere I read that excursions into the +7400 would result in Porsche declining to acceot offers to renew expired warranties. I am very happy with mine, but then again it was 18,000 miles at purchase and even now shows only 26,000. For my money if RH thinks its not an issue then privately I would disregard it but asa purchaser I imight be tempted to use that as a bargaining chip, 2002 80,000 mile 996t got to be around 22ks worth.

 

[912UK]

he is asking £26500 we where looking at less anyway due to general condition of the car.

As of this morning the chase is onto another car but it's a tiny bit further north, both in terms of distance and price point but it's clearly a better car and also an S with X50 but ceramic brakes hmmm no thanks but I understand these can be swaped out.. any one fancy a swap ! LOL

 

[924nutter]

£26500 is too much money in my opinion, unless it has a 40 mil thick folder full of service items and evidence that things like the coffin arms have been replaced. At 80,000 miles they are going to be worn. A guy in our region bought a 99,000 mile turbo for 19,000 but to be fair the dealer's arrogant attitude cost him dear. I won't mention names but he put the car up for sale before he looked it over properly, and my friend went to the dealer's and put down a £500 deposit. The dealer rang and said there had been a mistake and the car should be retailed for £25,000, and it should have been too, having seen iy in the metal, but my friend would not budge, so the dealer lost £6k. The point here is that a 99,000 mile car with a burgeoning service history was £25k so that 80,000 miler would need to be close to brand new looking for it to be £26.5k. I paid £36, 250 for mine Fred but it was at 17,800 miles in 2012. no typos here. On the fourcourt, as a cabriolet, it should have been £40-41, but he had only been offered £34 on trade in so he cut his losses for a quick sale and I benefitted. Never buy the first one you see, there are always others. I trust you are searching gum tree exchange and mart, as well as P/H and Autotrader. I know I always say I bought my 944 T cab from ebay, sight unseen and strictly spaeking that is true, however the car had been in a showrooom on the south coast for £17,500 but the owner had knocked the price down without letting the showroom know; so if you find one there don't rule it out. Good inspection is a must and if it seems too good to be true then, as 996t go, it probaly is.

 

[912UK]

thanks for that, we had passed on that car in question as it was in real terms a project car.

Paint issues, engine knock ( small but not going away ) front suspention and over rev. So all in all the more I looked at it the more I had £19k in my head and even then we didn't want the extra work.

Now we have seen another car it's much newer, higher spec but £2k out of budget. I know it's 2k but it could be 100k for all I care it's still out of budget. At the end of the day we are looking for a Turbo Cab in the winter so there can't be many of us buyers looking for this spec I would like to hope.

So it's our buyers Market I hope.

 

[Chris_in_the_UK]

UWM - are these the same people who advertise the engineering own goal referred to as the 'zero clearance turbo'?

 

[Richard_Hamilton]

John, I'd be wary of posting Autotrader links which show your post code.

 

[924nutter]

Well Fred should have had time to read them so its delete time

Fred of you haven't seen the three links to 911 turbos there were three worthy of consideration all under 22k and under 90,000 miles. So much car for little money. Not cabs but I think you might struggle to find a cab at 22k. I think the cabs might come in at 27k, unless you want my rare 944 T cab for 14 and a half. Just had a new hood. 46,300 miles.