Here goes:
When I purchased my first 928, this one, I thought the TB/WP issue was dependent on mileage only and since it was done at 99,000 km and I now have 122,000 km, I figured I was safe for a couple of years. WRONG (NAIVE) it seems. The TB was last done in 2002 July and it's been almost 12 years now. Am I safe if I get the TB checked by a mechanic and re-tension the TB to spec, to use this car at all ?
I know that everyone says 4 years max, even Porsche dealers, but if it's inspected properly can I do without for a couple of years ?

My expertise is in Server Support and not mechanical, and I am very afraid of doing it myself for the first time since it is CRITICAL that all timing aspect of this 32V motor are bang on, otherwise bent valves.

Now this car has been a dream of mine for many years and I would not want it to become a nightmare because of bent valves, motor rebuild.

I do have the WSM in PDF format, would have to print them, but also I don't have certain tools yet acquired to do this type of work. I live in Gatineau, Quebec and did not have the money yet (around $2k) to get the job done by trained mechanic. Should I park this vehicle which I just purchased this November 2013, until I can do this work even if I get the belt inspected first.

Opinions please. This is very disappointing to see that waiting all winter to find out that I should not drive this car because of the chance of the TB letting go.

Thank you in advance.
Andre

 

This is how 928s that would otherwise soldier on wind up in the breakers yard. Buyer gets one that needs typical service, and cannot or will not have it done or do it oneself. I know, I've had a car sitting on a lot for more than 5 years due mainly to frustration. It should be back in service, but I don't want to hassle with it much anymore.

So, back to the TB/WP issue at hand. I would not trust a 12 year old belt, no matter that there is technically no time limit on the job. The cost of a failure is just too high to risk. So, either have the work done, do it yourself, or park it.

My suggestion is to learn the job from the resources here on rennlist, gather up the needed tools, and spend a weekend at it. Everyone will help, and it's not a painful job, just time consuming. Nothing that can't be done by a modestly handy person, if they take their time.

 

Andre,

No one can tell you whether you are safe but we can sure tell you you were stupid if it snaps! If your motor is an interference motor then taking the risk is just dumb *** dumb. Rubber likes to be flexxed to keep it flexible- a characteristic of molecular behaviour so if does not get used or is liightly used this may well be the worst thing for the belt.

If it was my 928 and I knew the belt was 12 years old I would be reluctant to turn the motor by hand to get it to the locking position at 45 btdc on No1.


Your choice.

Regards

Fred

 

Even more disappointing if that belt goes! And there really is no reliable visual inspection, which is why a mileage/age limit is the yardstick applied to belt replacement. So, that said, all is not lost. Do you have tools and a place to work? Just as important, would you want to? This job requires patience, and a couple of special tools, which you may be able to borrow. Additionally, besides the excellent write-ups here on the list, there is a step-by-step printed guide which IMHO is the thing to get, be glad to send more info if you are interested. And of course, the "live" help members here can provide- invaluable. You should also seriously consider a new water pump (a search will tell you the Laso from 928srus is the thing to get), unless you want to use the TB job as a rehearsal for the WP job .

All that said, if you don't want to do the job yourself, save your pennies and have a pro do it. That's a lot better than seeing it end up in a breaker's yard, and you will be more than rewarded when you do get to finally get to take it out and enjoy driving it.

 

To be fair, that's what a lot of sellers want you to believe.

I would not trust a 12 year old belt - many more recent cars specify 6 years. I will be changing mine every 4-5 years, even though it will get less than 20k miles in that time. I see it as insurance.

 

Just to put your worry into perspective I was still driving my early '86 when it had a 17+ year old belt and 50,000 miles on it since last change...with the tensioner bone dry and giving me the warning light. Obviously I was running my luck thin every time I started her but I'm just saying that there have been much more severe cases of age and mileage where the belt hasn't broken. There's cases that are otherwise, however, you shouldn't worry the moment you crank the engine it will just snap like that. I would just throw caution and not drive her hard if you need to move her around. You need to check the condition of the belt. Any cracks or tears or signs of major wear, even placement on the cam gears and migration should be addressed. Anything that looks off, don't run her. You should be more worried about the water pump seizing as that will cause the belt to break.

Learn to do it yourself or else you're going to be paying major bucks to someone who may screw it up unless it's a dedicated 928 mechanic and will still be around every 4 years you have the car. I don't subscribe to the strict 4 year interval but I probably wouldn't go over 6 without changing it and the WP and checking them both once a year before then.

 

Prior to having the front end of the engine done on my 85 S2 - I ran it for 8 years (track use) with the belt that came with the car. no records prior to that. Periodic inspection was the only thing that was done.

After developing an oil leak on the front crankshaft seal - I went ahead and redid the entire front engine.

Timing belt, water pump, o rings, seals and everything else. The final bill was almost 3K - It's been almost a year and half since then and I have only put 2-4 hours on it tops by just warming her up an driving her around the neighborhood.

YMMV -

 

Well, at least you are asking the right questions now. You could turn the key any number of times and it might not give it up til the next one. But it might be the next one.

There is plenty of help here if you decide to do it yourself. Other than basic tools all you need is a breaker bar, a 27mm deep socket, a flywheel lock and a torque wrench. There are step-by-step guides here (more than one) and if you take your time you can do it. "Want" is the key word. If you want to do it, it isn't rocket science. It isn't easy, but it is pretty straight forward.

The peace of mind and the sense of accomplishment are priceless.

http://dwaynesgarage.norcal928.org/1...0Procedure.htm

Read Dwayne's thesis; probably the best way to get a feel for it.

 

I would be even more concerned if the timing belt is that old...how old are the fuel lines??? TB goes its the motor...fuel lines go its the car and maybe more. New fuel line kit is cheap and takes a novice a day.

Do you have a place to work on it?? The only "special tool" need is a flywheel lock. ..what $60 usd. Belt, new water pump, rebuild tensioner....$600 usd. You can do it.

Any other owners local that can give hands on advice?

 

Thank you very much every one for the encouragements and info . I will get it inspected at least to see the condition, and if the condition is still good, not cracked or dried up then I might save up some more dollars to do it myself with the help of a knowledgeable 928 owner here in Gatineau. At least I will understand how everything is working together. I will purchase the necessary sockets, torque wrench and parts required. I guess for the WP I'm better off purchasing a Laso with plastic impeller, no metal impeller as for what i gather from the many posts I read ?

I agree about rubber drying up, so that is why I am concerned.

At first I told myself that if I don't slam on the accelerator hard there will be less torque on the belt and that might help me to keep from having a disaster. But again I will not be pushing my luck long since this is probably the only Porsche I will be lucky enough to have. It will be babied as soon as I can.

At least the fuel lines have been changed in 2002 as per maintenance records when it came out of long term storage. I did check that after I read up on some posts about cars catching fire and why.

 

I've pulled original belts (Made in W. Germany) a few times and they looked perfect but would never trust them due to age. Take the time and $$ to get it done as you'd hate to be driving around thinking each day "man, this could break and I could be pooched" You will sleep better at night knowing it's done right.

I say yes to the Laso pump, not the eBay special or some of the rebuilds. Take a good look at those fuel lines and ensure they have been done. I pulled this hose pictured below off an '85 yesterday. Looked good on the top. It got a bit hot at some point in its life and someone didn't change it.

 

Don't bother rebuilding the factory tensioner and spring for a PorkenTensioner. Check seals and all that while you're in there.

Doing it by yourself, I would allocate $1,000 towards the job. That should be more than enough to cover tools and parts for the job. IF you need to change your cam gears add $600 more but given the mileage you probably don't need to. Your car is low in miles so I don't think gear wear would be extreme.

 

Thank you again, everyone. Yes the full lines have been done in 2002, but once I know where they are on this '85 I will re-check them again to be safe. Last time I checked the hoses from the tob all looked fine, but better be sure.

Yes I am finally doing the TB/WP job, thanks to my friend Bertrand. He will guide me to start and I will print the step by step instructions provided in this post from Dwayne and read through it a couple of times to make sure I understand everything. I will also by the Laso pump and porken tensioner from Roger, I have to email him on that today.

It saddens me that I will not be able to use it this year, but it would sadden me even more if the motor crashes !

Thank you all again for your support.

 

Dwayne's excellent write-up is for an S4 of course. If you find puzzling differences you can consult another excellent source, John Kelly's 62 page "Timing Belt Manual for the 1985/86 32-Valve". I don't know if it is still available, but this thread indicates it might be: https://rennlist.com/forums/928-foru...available.html . It also refers to some of the possible differences between our engines and the S4. I'll be glad to PM you the email address I have for John, and if the manual is no longer available I can scan pages that might answer questions that come up. TB/WP was the first job on my 928, thanks to this forum - before I did it I had driven the car onto and off the trailer I brought it home with and that's all. The state of maintenance was obviously so poor I knew I could not trust it.

 

There was a recent thread for an 86.5. By a guy who had never done it before.

It's very detailed and thorough. He points out any "Non-obvious" issues, and doesn't hesitate to ask questions. And the answers from the "usual suspects" are spot on (Which way did that washer go?)

You have an amazing resource on here. Don't hesitate to use it.
There are a bunch of guys in the Toronto area, it's not right next door, but it's not too far, especially if it gives them a chance to take their cars out. You might think about throwing a "Timing Belt Party." Food, drinks and wrenching.

The question about age comes up a lot. Much of it depends on the conditions where the car is. Cool and not too dry tends to make them last better. Hot and dry, like in the desert southwest here in the US, ages them much faster. But in any case, 12 years is a long, long time.

Thread:

https://rennlist.com/forums/928-foru...rst-timer.html