'82 928: Necessary to preemptively replace timing belt?

[oACGo]

This is my first post here:

I just recently got a 1982 928 with 80,000 miles. It seems to be in great shape. I don't know a lot about cars in general, or these specifically, but I'm starting to learn (slowly).

Anyway, I brought it in for an oil change and the mechanic stressed to me several times that I should replace the timing belt if I don't know when it was last replaced (which I don't). This was just based on his experience with the damage that can be caused if a belt breaks when the engine is running, not because he saw anything indicating a problem.

After doing some reading, it seems like that is particularly true on the later, 32v 928s, but it's not clear to me how necessary it is for a 16v 1982. This document (http://928intl.com/repair/T-belt1.pdf) says:

The factory-recommended replacement interval for the timing belt is 60,000 miles, but more conservative or pessimistic owners often observe shorter intervals, such as 40,000 miles. There is general agreement that age should also be a factor, with replacement suggested at no more than every four years, no matter how much or little you've driven in that time. If you don't know when your belt was last replaced, you should seriously consider replacing it, especially on a 32-valve engine.

What would you do?

For fun, here's a photo:

[harborman]

Hello, Nice car, looks real clean. I believe the 82 timing belt is not as critical as my 86 which is a 32 valve engine. The 32 valve is what they call an "interference" motor, meaning the pistons can be damaged with a broken timing belt. Anyway, if the belt has never been replaced on your car it would be a good idea to do it just from the age. Others here with your type motor can give you more info.

[JK McDonald]

Hey ACGo - Welcome to the site and congratulations on your new 928. If you didn't get any maintenance documentation with the car you might ask the previous owner about the status of the timing belt. Like Harborman mentioned, if you aren't sure when the timing belt was last changed it would be a good idea to replace it. It is kind of a pain in the A$$ but you can get some idea on how the belt is doing by pulling the left and right top half of the belt enclosure for a general inspection. Look for any sign of the belt's teeth missing, frayed or shreding edges, areas of the belt that's obviously worn down or excessive black powder from the belt rubbing against anything. These are also signs that the timing belt tensioner may be failing as well.

There are several write-ups on the list of accompanying parts that are recommended to be replaced along with the timing belt. Changing everything all in one wack will actually save you a lot of heart burn in the long run. If you do the job yourself, you will also need a couple of relatively inexpensive tools - "Timing Belt Tensioning Tool" and a "Fly Wheel Locking Tool". They are very important to do the installation correctly and easy to use.

https://928motorsports.com/parts/cambelttensiontool.php

https://www.google.com/search?q=928+porsche+flywheel+lock&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwilj8mL7JDTAhVGRSYKHRhVAE0QsAQIOQ&biw=1025&bih=522#imgrc=fELjUwfQ_3lmuM:

The 1982 U.S. 928 version does not have an interference motor which means if the timing belt is way out of adjustment, too loose or (worse case scenario) breaks causing the crank and cams to jump time, the valves do not hit the pistons.

Don't hesitate to ask questions - There are lots of very experienced 928 owners available to give you all the help and advice you may need.

Good Luck and again welcome aboard, Michael

[oACGo]

Thank you both for your replies. I did receive some maintenance paperwork, but I'm certain it's not thorough. I believe this car was totally "restored" around 5 years ago (only a couple thousand miles ago. It's likely that these parts were replaced at that time, but I can't prove it. I'm not sure if I'm up to the task of doing the job myself as I have no mechanical experience and this is all new to me, but I also know that won't change if I don't try and learn. I just don't want to screw anything up! I may have the contact info for the shop that did the resotoration work, so I may reach out to them. That said, even though very few miles have been put on the car since that time, it's still been a number of years.

[harborman]

Originally Posted by oACGo

Thank you both for your replies. I did receive some maintenance paperwork, but I'm certain it's not thorough. I believe this car was totally "restored" around 5 years ago (only a couple thousand miles ago. It's likely that these parts were replaced at that time, but I can't prove it. I'm not sure if I'm up to the task of doing the job myself as I have no mechanical experience and this is all new to me, but I also know that won't change if I don't try and learn. I just don't want to screw anything up! I may have the contact info for the shop that did the resotoration work, so I may reach out to them. That said, even though very few miles have been put on the car since that time, it's still been a number of years.

Contact the shop that worked on the car and get a copy of everything they did if possible. If the TB was done recently and even if it has 5 years on it with low miles, I would just do an inspection. To do this work yourself with no prior mechanical experience might be a little difficult. Try and locate another 928 owner near you, maybe find the local PCA Club, go to a meeting and hopefully meet another 928 owner. They might be able to help you out.

[Mrmerlin]

remove the top fan shroud with 2 bolts, and the intake air tubes
pull the 1-4 cam cover off and look at the belt,
take a few pictures and post it ,

NOTE to turn the crank you need a deep 27MM socket

what your looking for on the outside of the belt is printing,
if you find clear printing then there is a good chance your belt is fine/new and the tension is all you need to check.

NOTE look at the rubber on the back of the belt does it look fresh or do you see lots of little cracks like old tires get?

Are their any oil or coolant stains on the belt if so replace it.

If it looks fresh then your belt is OK if it looks cracked then its time to replace it and fix the leaks.

To check the tension,
the engine is cold,
then timing marks are lined up at TDC,
the cams have a small cut on the back that lines up with the cam tower,
not necessary to remove the 5-8 cam cover just loosen it to peek behind it.

while facing the engine always turn it clockwise.

Use a Kempf tool , tension should be at the low side of the window for the early 16V

[Mrmerlin]

Note 1-4 cam is on the passenger side of the car for USA cars

[stepson]

If you feel comfortable doing everything that Stan (MrMerlin) has directed you to do in the 2 previous posts, go for it. It's not that hard and is a great way to get to know your car.

On the other hand, if you are not comfortable doing those things outlined above, take your car to Greg Brown at Precision Motorwerks in Anaheim.

If I lived in that area, and I needed my cars repaired, I would go to Greg Brown.

If I lived in the northeast part of the country, I would take my cars to MrMerlin. (Stan)

If I didn't work on my own cars, since I live in DFW, I would take my cars to Sean at 928Docs.

If I lived around Kansas, I'd see Mo Zahr in Wichita.

If I lived in the NW, I'd go see Colin.

[Mrmerlin]

Thanks John

[stepson]

Stan, I have no doubt that if someone brings a car to you, you would do the right job the right way.

To the OP: a Porsche mechanic does not mean a 928 mechanic. Please do not pay someone to learn how to work on your car. If you decide not to work on the car yourself, use a 928 mechanic.

In addition, your car does not have an interference engine. If the timing belt breaks, no catastrophic damage to your engine will occur.

That being said, it would be better if you make the determination when to replace your timing belt rather than end up on the side of a desolate roadway somewhere when your car has determined for you that you are going to replace the timing belt.

[oACGo]

Thank you all for your time and advice.

I have emailed the group that apparently did restoration work on the car back in 2011 (anyone familiar with GK Restorations in Florida?) and Beverly Hills Porsche who worked on it in 2014 requesting any details they can give me. I still need to reach Stuttgart Automotive in Santa Monica who most recently worked on it prior to me owning it.

Mrmerlin, thank you for the detailed instructions. We'll see if I'm brave enough to dive in.

Stepson, thank you for the heads-up that Porsche mechanic does not equal 928 mechanic. I didn't realize they're so specialized that it would make a significant difference. Very good to know and definitely gives me pause about bringing it back to the german auto shop where I got the oil changed.

[Jim Chambers]

John, I live in the NW. Who and where is "Colin"?

[stepson]

Originally Posted by Jim Chambers

John, I live in the NW. Who and where is "Colin"?

Lizard928 on RL
Colin Jensan
in Abbotsford, B.C.

[Blaise805]

Hey oAcgo I live in Ventura county and have the belt tensioner tool. I have a 1982 euro model and can help you with the timing belt. Feel free to get back to me I haven't seen many 928s around here.

[oACGo]

Originally Posted by Blaise805

Hey oAcgo I live in Ventura county and have the belt tensioner tool. I have a 1982 euro model and can help you with the timing belt. Feel free to get back to me I haven't seen many 928s around here.

Wow - that's awesome. Thank you for offering to help! I'll shoot you a private message.

[Blaise805]

cool it would be nice to see another 928. Stan is a big help and is generous with his knowledge of these cars.

[oACGo]

Originally Posted by Blaise805

cool it would be nice to see another 928. Stan is a big help and is generous with his knowledge of these cars.

Right on. I can see that he is. The instructions seem very clear, I'm just so inexperienced that I fear screwing something up.

[oACGo]

Originally Posted by stepson

...take your car to Greg Brown at Precision Motorwerks in Anaheim.

If I lived in that area, and I needed my cars repaired, I would go to Greg Brown. .

I just picked my car up from Precision Motorwerks and it feels great.

My car had a pretty good check-up, but my goal was to make it totally mechanically sound/maintained/safe, so I took all of Greg's advice which included replacing the aluminum ball joints with steel, replacing the center resonator, some deteriorating wiring, and incorrect or aging hoses; Alignment; Fixing leaks; Tightening clamps and bolts, etc. I also came in with a list of minor things that were more apparent to me and they knocked those down, too.

I didn't even catch a hint of curmudgeon from Greg. Greg, Mary and their team were fantastic. I can't recommend them more highly. Definitely worth the train rides to and from when I was dropping off / picking up!

Thank you for recommending Precision Motorwerks!