mickster

I think James Morrison has a well sorted car from around that time for sale...

fltechpilot

Ok thanks for the input guys. Extremely helpful! I'm very glad I decided to register for this site. I'll definitely become a member whenever I end up making the leap.

3000teeth

Agreed about the price. $3500 is too high for that car, considering the paint and the records.

fltechpilot

Well here's an update. I bought the car and got it home last night. Took the passenger side tb cover off and the tb tension was unbelievably loose. That is definitely where the rattle was coming from. It's so loose you could slide it off the front of the cam gear if you wanted to. what could have led to a belt getting this loose?

Also, I'm in the process of ordering parts for a tb/ water pump/ tensioner rebuild. It looks like the only tensioner arm bushings available are for 85 and up cars. Will that part work on my 84? Also, I need two of those bushings, correct?

fltechpilot

I apologize for the poorly written previous post. I banged out that masterpiece on my little phone screen.

I was fully expecting the rattling noise that i described in my original post to be from the timing belt. However, I certainly wasn't expecting it to be as slack as I found it to be. I'm very curious to hear what your opinions are as to how a belt could get to this point and I will update this thread when I have the time to remove the remaining tb covers. Thanks for all of the help so far. It's amazing what I've learned about these cars in just the past two months from this site!

Bill Ball

Not seen one spontaneously that loose. I suppose the tensioner adjusting lock nut and bolt could have backed off (I blue Loctite the bolt threads). A very worn water pump bearing might allow the pulley to cant upward enough for the belt to be quite loose. A bent shoulder bolt that holds the tensioner arm pivot would be a possibility. Get the covers off.

Podguy

Getting the correct bushings for the tensionor is critical. Since your car is an 84 and a non interference engine, I would tighten the belt a little and run the enging a bit before you tear it down to look for other issues. One I would look for is a loose cam pully and maybe a damper pulley that has separated.

When the tension arm bushings are worn then the tension arm will tilt foward. The belt then walks forwad and would just slip off except for the damper wheel holding it in place. The damper wheel rubbing against the belt will produce a lot of fibers which should now be trapped in the convers.

While you still have the engine running look for oil leaks. Most common are the front seal that should be replaced with the belt, the rear cam covers which can be cured with a silicon gasket and the oil pan which is a real pain to change in the car. Check the motor mounts for collapse and the rack boots. The rack can leak but the boots hide it. You need to pull back each boot - unless torn - to check. if your steering when turning around in the drive is notchy or jumpy then the rack is leaking. If the cam pulley is worn or lose and the inside key has damage then you need one or both new pulleys.

Have fun with your new car.

brutus

No way of knowing how tight the previous mechanic set the belt or when !

Pappy

Congrats on your new toy! My first 928 was an 84 auto. Loved it! Great year to learn on.

fltechpilot

Thanks for the great ideas and recommendations everyone. I took a couple pictures that I think capture the slackness of the belt. I'll post them when I have a chance.

Additionally, the tension of the belt under both cam gears seems to be reasonable. The top part of the belt that comes over both cam gears is completely slack. Would this point to a water pump issue? If I understand the belt layout correctly, the water pump is the only thing providing tension to the top part of the belt.

The car was running at a normal temperature, so it seems that the water pump was still operational.

brutus

You get various tension depending on which and how many valve springs are compressed as you rotate the crank. It is only meaningful at TDC with the cam marks up. You need a Kempf tension tool and the instructions about how to use.

Strat_928

I have an 83 Auto and it looks exactly as does yours body-style wise. My doors are the same at the bottom as well. But as others have said and you may read elsewhere, the 16v non-interference models of 83 and early 84 are likely to be the cheapest and least complicated to maintain and get running reliably. A great learning platform in any case. But although it is underpowered (especially mine HA) compared to the 32v models of 86.5 and up, you might be pleasantly surprised at it's capabilities once you have everything sorted out. It is not a drag racer, it is a GT car. Handles like nobody's business.....For performance upgrades (unless you pay for supercharging) you are pretty much looking at the exhaust, no computer chips for these years. The auto can also be shifted nicely and is built strong and is responsive. The exhaust especially can be a nice performance upgrade on these models. Get some 85/86 exhaust manifolds, get a y-pipe or x-pipe if you prefer, then upgrade the rear exhaust as well. Pay for a injection cleaning using BG products, as well as a fuel system clean out as well. Make sure the electrics are tight, especially grounds, maybe get a 115 alternator instead of the OEM 95....off you go!

Enjoy

I love my 83, I am sure you will enjoy your 84! Lets us see pics as you progress.

fltechpilot

Took out the upper fan shroud, fan, radiator hoses, and I'm in the process of removing the accessory belts. I loosened the center timing belt cover and I can reach in and spin the water pump pulley by hand with the belt in place.

NoVector

If you don't already have it, I'd also include a fly-wheel lock and the workshop manuals on CD. Roger can get you what you need.

Although it's a different MY, Dwayne's TB/WP page will probably help. It's at:
http://www.dwaynesgarage.norcal928.o...0Procedure.htm

928porschemangreg

I can help you with this if you get stuck on anything.
-Greg