924Board.org

joecitizennn · Joined: 12 Sep 2005 Posts: 2096 Location: no mans land

Having acquired an 88 porsche 924S just a few days ago, i have had alot to learn in a short span of time. I am going to replace all the belts, and any bearings that show any wear. I have already noticed a few tiny fibers pulling loose from the teeth on my balance shaft belt. NOT GOOD. The balance shaft belt is more expensive than the regular timing belt, and I heard someone mention that it is possible to leave the thing off, and run the car with the balance shafts dead. Is this a common practice? Has it been proven to not affect the car in any way wearwise?

I will have to assemble the engine with the belts at the proper tension, and readjust shortly, as belts tend to stretch slightly under use. Not only this,, it seems to be necessary to check the tension on these two belts every 7500 miles or so. I can only assume that a Porsche 924S, or 944 owner must have one of these tools. Absolutely!! I have been looking on ebay, and have so far seen two types, one was just a couple peices of sheet metal and a spring. It had angles and notches cut in it. It sold for 50 bucks. I also have seen a tool with both a dial guage, and a seperate sliding guage. Which is better? I am not made of money, so I want the cheapest option that actually works. Mayby someone will point me there.

Paul · Posted: Sun Sep 18, 2005 4:00 am Post subject:

Please do a search for "timing belt" and type "Gohim" in the author box.
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White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.

Paul · Posted: Sun Sep 18, 2005 4:09 am Post subject:

Here's a good thread:

http://www.924board.org/viewtopic.php?t=12525&highlight=timing+belt

timstar92404 · Joined: 22 Sep 2004 Posts: 2075 Location: richmond BC

I think it would be a bad idea to leave the balance belts off... the 2.5l 4cyl would probably produce much more vibration don't know if thats just an annoyance or if its bad for the engine also.

probably bad for your motor mounts.
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78 924 sold.
85.5 944

gohim · Joined: 02 Nov 2002 Posts: 4459 Location: Rialto, CA

You can save all of maybe 5hp by removing the balance shaft belt. On a street driven car there is no reason to run without the balance shaft belt.

You will also get more vibration without the balance shaft belt.

Personally, I would worry about the additional vibration causing or accellerating fatique cracking of the oil pickup tube. It is uncommon, but there are documented cases of the oil tube-up tubes cracking (causing loss of oil pressure, and lubrication) in several cars. As a result, the oil pickup tube is one of the items that is supposed to be inspected carefully for cracks when the oil pan (engine rebuild?) is off for that reason. Why go looking for trouble to save a few bucks on an expensive scheduled service?

As far as the tension measuring tool goes, personally, I would not risk my engine. You get what you pay for, and if you go cheap, you die ! ! !

But it's your car, and it's your wallet.

Llamaguy · Joined: 02 Jul 2003 Posts: 711 Location: Indiana

I took mine off, for the sole reason that I couldn't get the damn thing aligned. I didn't experience any more vibration. Be warned, you will leak oil for awhile until the balance belt seals get settled.

BUT this is my personal experience, your car may be different.
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1987 924S Guards Red
1997 Suzuki Tl1000 Supersport

Lizard · Posted: Tue Sep 20, 2005 1:42 am Post subject:

Llamaguy, the balance shafts alignment is pretty tricky as the passenger side cam actually is aligned when 180 deg out of rotation from the drivers side cam.
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3 928s,

joecitizennn · Joined: 12 Sep 2005 Posts: 2096 Location: no mans land

why not mark each balance shaft sprocket, when the cylinder is at Top Dead Center? I mean, first thing when you remove the belt covers, take white paint, and mark the balance shaft sprockets while cylinder number one is at TDC? Then after you tension your cam belt, just make sure cylinder one is at TDC and make sure that the painted marks you put on the sprockets and the metal behind them are lined up perfectally! Cmon, it is a no fail situation!
That is how I am going to do it.

gohim · Joined: 02 Nov 2002 Posts: 4459 Location: Rialto, CA

For your plan to work, you would have to ASSUME that the balance shafts are already in perfect alignment...

Being the cautious sort myself, I never assume that the guy that did the work before did everything. Too many times I have gone in to repair a car, dishwasher, television, etc, and found that someone who had been in there before me assembled something wrong. Often times, the incorrectly done work caused the problem/s that I went in to fix. AND, ULTIMATELY, I am responsible for the results of any work I do. So, I am going to make damn sure that everything is correctly reassembled when I am done, EVEN IF IT WAS INCORRECTLY ASSEMBLED WHEN I STARTED.

joecitizennn · Joined: 12 Sep 2005 Posts: 2096 Location: no mans land

Just get a haynes manual and read carefully. They tell you how to do it.