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Posted by: Series9 Nov 13 2010, 05:36 PM

$

This happened to Nelson today while I was visiting:




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Posted by: jimkelly Nov 13 2010, 05:38 PM

i take it this is an interference engine?

Posted by: Series9 Nov 13 2010, 05:40 PM

IIRC, 11.3:1

Posted by: dion9146 Nov 13 2010, 05:41 PM

Uh, yup.

Exactly why I won't own another one.

Posted by: okieflyr Nov 13 2010, 06:41 PM

Sorry about that Nelson. It may be cheeper to put an LS1 in there and have a sleeper.

Posted by: rick 918-S Nov 13 2010, 06:53 PM

Oooohhh... That'll leave a mark! Maybe you'll get lucky and it will only be bent valves not broken pistons and gouged cylinder walls from the broken pistons. Ask me how I know...

Posted by: sixnotfour Nov 13 2010, 07:33 PM

chev it



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Posted by: KaptKaos Nov 13 2010, 08:19 PM

What is the disadvantage of a non-interference engine?

Posted by: Rick L Nov 13 2010, 08:22 PM

That's NOT your typical belt path or configuration!

Tell me the valves are ok?!

Posted by: rick 918-S Nov 13 2010, 08:25 PM

Not a snowballs chance in hell my friend.

Posted by: Lennies914 Nov 13 2010, 08:37 PM

OUCH !! It even hurts to look at.

What a bummer.

Posted by: Ferg Nov 13 2010, 08:46 PM

Posted by: r_towle Nov 13 2010, 08:54 PM

It may need a new head.
If you give up, let me know...I might be interested in buying it.

Rich

Posted by: Series9 Nov 13 2010, 08:56 PM

The valves that were closed at the time are fine.

Posted by: jasons Nov 13 2010, 09:02 PM

My S2 stripped the belt teeth on start up. I lost all 8 exhaust valves, no intake valves. That belt had around 40k on it. I also had the clutch fail. I wouldn't touch another one of those cars.

BTW one of my good friends is doing an LS1 conversion on an S. I am guessing he is well over $10k invested in just the swap by now. But he hasn't cut any corners either.

Posted by: Gint Nov 13 2010, 10:46 PM

Yuk. I'd like to see pics though.

Posted by: Garold Shaffer Nov 13 2010, 11:50 PM

How many miles on that belt? When I had my 88 944 the belt was replaced every 30k and not 1 mile over that. Also pulled the cover and inspected and checked the belt tension to make sure things were good once a year.

Due the proper maint work on a 944 / 968 and they will last a long time. I'm not saying this 968 wasn't maintained properly, stuff happens even when you do. Hopefully it's just bent valves.

Posted by: rfuerst911sc Nov 14 2010, 05:33 AM

I had a 1987 944S it was a nice car. Had all maint. up to date and the timing belt only had 15,000 miles on it when it snapped. Bent a bunch of valves so I sold it. I will never own another. It's a shame as they are nice handling cars with room in the back with the hatch but these engines should have had a timing chain or just gears.

Posted by: Racer Chris Nov 14 2010, 06:40 AM

Rubbernecker.

Posted by: jasons Nov 14 2010, 08:17 AM

I'm not going to disagree with you. But, a car that needs a timing belt every 30k and a $500+ tool to tension that belt is a fail.

Its a shame because they got a lot right on those cars. They are still attractive cars (especially the 968), and they don't rust. Its the clutch or timing belt that puts them in the junkyard.

Posted by: SLITS Nov 14 2010, 08:24 AM

Joe, the "disadvantage" of a non-interference engine is that when the timing belt shreds, you would, in theory, not have pistons hitting all the valves. Maybe one or two since they would be open, but a much less expensive repair much to the chagrin of Porsche, Porshce parts suppliers and shops.

Actually, most non-interference engines have lower compression ratios = less horsepower.

Posted by: rick 918-S Nov 14 2010, 08:57 AM

And these known defects kick the snot out of the value. Too bad too because the cars are dead sexy. I'll never understand why Porsche didn't use a chain on these and the 928. There's a development project for Series9.

Posted by: sixnotfour Nov 14 2010, 10:32 AM

There is a chain between the exhaust and intake cam , vario cam, another source of problems.

Posted by: BMXerror Nov 14 2010, 11:59 AM

Too few of those made! Don't you f*cking dare!
Mark D.

Posted by: KaptKaos Nov 14 2010, 12:46 PM

It was an oddly worded question to be sure. In other words, why wouldn't a company make all of their engines non-interference.

I assumed that compression levels would be lower, but wasn't sure.

Posted by: Madswede Nov 14 2010, 01:57 PM

It's not going to have an LS1.

There were a fair amount of miles on the timing belt. The irony is that I'd been planning on having it replaced soon, but hadn't done it yet. Intelligence=learning from others' mistakes. Wisdom=learning from your own mistakes. I'm getting pretty wise.

It's certain valves are toast, how many and how bad the rest of the cylinders and stuff are is a matter for another day when the head comes off and we have a look. Right now, I'm not really in the mood to take pictures and the full diagnosis will wait for later.

The ultimate plan was a turbo project for this car (long term), but here's hoping it can be resurrected as a naturally aspirated 968 again soon. It's gonna cost me, yes.

- Nelson

Posted by: Cupomeat Nov 14 2010, 06:58 PM

Good for you, 944s saw the same issues as Boxsters are seeing now. They got cheap so cheap people bought them and didn't do the (expensive, YES) maintenance, so they all got cheaper.

Thanks for keeping this 968 on the road. It is a great car.

Posted by: dion9146 Nov 14 2010, 07:18 PM

I had a beautiful 88 944S, Guards Red, tan leather, etc. 60K miles. I loved the car, but the maintenance costs ate me alive. First the water pump, so of course I did the belts, and of course the rollers. Then the exhaust went, then the clutch, then the heater controls, then the brakes started to go, then I sold it.....

I miss driving it. I don't miss owning it.

Posted by: sww914 Nov 14 2010, 07:39 PM

High maintenance girlfriends, those front engined Porsches.
Sure, they look really nice and they're fun to ride, but is it worth it?
Almost.

Posted by: RobW Nov 14 2010, 08:07 PM

Kaboom. Bummer. Sorry man!

Posted by: Madswede Nov 14 2010, 10:32 PM

I want to say that I really appreciate the sympathy, guys. It's truly nice to know I ain't the only one that's experienced this:

As to the car and it's situation (especially relative to a 914, which I really began to love after meeting Joe O'Brien and driving actual, running, fun 914s and buying my first one with a plan to make it a /6 semi-beast), owning a Porsche of any kind is a commitment to maintenance and care. True, the front-engine series by Porsche are known to be maintenance intensive, and I accepted that. I didn't learn from others' mistakes and now am having to pay for my own.

But really, when you get down to it, there are two main points that have driven (ha) me to own what I own: (1) I have a passion of driving performance automobiles that will die the very second I do, and (2) I own my possessions, they don't own me.

So ... here's to owning cars that, yes, frustrate and cost us $ ... and here's to the same passion of making them worth it. I ain't gonna let this hold me back from enjoying the road. (well OK maybe for a few months)

Thanks again for the sympathies! Hope to have more positive stuff to talk about when the 914 3.2 is at Series9 being built!

- Nelson

Posted by: Madswede Nov 14 2010, 10:48 PM

In the interest of open information, I wanted to address this a little more specifically. I'd appreciate it if this were taken in the spirit it is given (i.e. not looking for "OMIGOD WTF U THINKIN STOOPID" type comments here)

There were roughly 50,000 miles on the belt. Not a good number.

I drive almost exclusively highway miles, and very little of that is aggressive driving (which I know, doesn't really matter when it comes to timing belts).

I drive 1K miles a week, 4-hrs a day commuting over highways.

I've rolled double the miles the car had when I bought it 3.5 years ago (~98,0000).

I am not necessarily a cheap skate when it comes to car maintenance, but there are things I can do and things I have to find time to have local Porsche mechanics do (there's only one that I trust here after Series9 moved to Florida, and he's very busy).

So ... excrement occurred. The point is well-made, and in the future I plan to be a bit more diligent about other maintenance items in spite of the $ involved. But then again, I think these cars are worth it.

Oh and yes, I'm in violent agreement with you ... hoping like hell that it's just bent/broken valves! We shall see in a few months ...

Cheers all!

- Nelson

Posted by: jasons Nov 14 2010, 11:56 PM

I just think its a travesty that 50k is too many miles for a belt on any modern car.

From my belt experience with my 16v 944S2, I would guess you just bent valves. Its not a terrible job to pull the head either. I ended up doing it twice when a stupid plastic wiring harness clip found its way down an oil return galley after I had almost completely reassembled everything. Its hard to explain how it happened but my wife was involved and I watched the whole event play out in slow motion. Nobody to blame but Murphy.

Good luck with it, I feel your pain from my personal experience. And, my belt had less than 50k.

Posted by: Mikey914 Nov 15 2010, 12:48 AM

I had a similar experience in my 951. The belt stripped after the car had stopped and I attempted to restart days later, the good news was only one bent valve. As long as you weren't pulling any RPMs when the belt broke (and it looks like you weren't), you'll probably get off with maybe 2? As long as the reason the belt stripped was one because there was a cam issue. You'll know pretty fast when you pull the valve cover gasket if that's the case. Otherwise you'll just need to replace a few valves as a worst case. The sodium filled ones on the 951 ran $72 each, but if you're lucky, it may not be too bad.

Best wishes!

Posted by: Brando Nov 15 2010, 01:30 AM

Hello valves, meet pistons.

Expect a pretty penny for the headwork, if needed.

They really should have made it a timing CHAIN instead of the crappy cog-belt design.

Posted by: Brett W Nov 15 2010, 08:27 AM

I am pretty sure Len can do the head work. What kills me is Honda built the B16 back in 88-91, it made 160+hp turned 8000rpm and had timing belt intervals of 80-100K. And Porsche can't design a belt system that won't make it past 40K? Really? Because the few pennies saved on that cheap ass belt, really helped overcome the poor reputation Porsche gained from stuff like this?

Take out the Porsche 4 cylinder and put in an S2000 motor. That will piss off the purist.

Posted by: Cap'n Krusty Nov 15 2010, 09:31 AM

Generally speaking, it's the water pump that fails, taking the belt along for the ride. It usually, but not always, lets the driver know it's failing some time before it actually takes a dive.

The Cap'n

Posted by: my928s4 Nov 15 2010, 09:55 AM

I have seen a number of belts on 928's with the teeth stripped, not often you see a snapped belt.

Posted by: iamchappy Nov 15 2010, 01:05 PM

I've been thinking about pulling the engine on my 924S and see if i could put a GM V-6 in there, i think i would prefer it over the LS1 and way cheaper. Some of those V-6's have 300hp.

Every time i start the car i say to myself is today the day....i hate the worry....

Posted by: Brett W Nov 15 2010, 03:33 PM

How does the water pump fail? Bearing craps out? or locks up?

Posted by: sww914 Nov 17 2010, 11:18 PM

My WRX timing belt had 90K on it when I replaced it. It still looked fine, I was simply afraid to not change it. I think that the years had as much to do with your belt failing if not more than the miles. I've seen a car with almost 200K on the timing belt before it broke. I can't recommend that.

Posted by: Mikey914 Nov 18 2010, 12:16 AM

Good news is the 951 (I assume the S2 would also) has a rebuilt option that is only about $100 fromt the dealer. I have replaced it and got about 45k on it before the fire. Got it as Sunset. How are the cams? any problem with the chain and tensioner on the cam assembly?

Posted by: Mikey914 Nov 18 2010, 12:17 AM

Bearing usually get pretty loud before it lock up.

Posted by: cary Nov 18 2010, 08:00 AM

I did both my kids cars a couple years ago. Both at about 70k. Escort and an Audi A6. The Escort no big deal. 2 beers. The Audi, a whole 12 pack.

Posted by: Brett W Nov 18 2010, 08:34 AM

And it required every tool in your tool box. The Escort was done with 3 sockets.

Posted by: Madswede Feb 10 2011, 08:49 PM

Joe was here working on the 968 today. It turns out that there are two EDIT: four to six bent valves. Pistons look fine. Probably a candidate for rebuilding the head. Looks like I dodged a big ass bullet! Pics to follow later on, right now I'm just very, very relieved.

EDIT: Pics will show at least four exhaust valves are not making a seal at all, intake valves appear fine. *whew* Coulda (maybe shoulda) been much worse.

- Nelson

Posted by: Madswede Feb 12 2011, 01:23 PM

Bent valves...


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Posted by: Madswede Feb 12 2011, 01:24 PM

... and ...


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Posted by: Madswede Feb 12 2011, 01:25 PM

... and ...


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Posted by: Madswede Feb 12 2011, 01:25 PM

... and ...


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Posted by: Madswede Feb 12 2011, 01:26 PM

... the pistons are slightly dinged ...


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