924Board.org

Eric P · Joined: 21 Jun 2017 Posts: 175 Location: NY, USA

On this week's interactive episode of "Something Is Broken On My 924":

I finally got my 1980 924 NA (US) running well and drove it for about a week. I was having a problem with the alternator belt squealing at lower RPMs. Last night my lights were getting dim on the way home and this morning I went outside to start the car and *click* dead battery. I'm assuming that either my alternator bit the dust or the belt was slipping enough to cause the alternator to not put out enough power. The old belt is still on there, but not very healthy. The belt has about 3k miles on it but the car hadn't been driven for about 5 years, so the belt is old and hard. I'm going to start with a new belt then test the alternator.

I was looking at the alternator and wondering how to tension the new belt. It looks like my car has 2 bolts... one pivot bolt at the top and a bolt to lock the alternator in place on the slotted plate under the alternator. Is there another bolt under the alternator used for setting the correct tension? Or am I supposed to pry on this thing? The Haynes manual basically says loosen both bolts and tighten the belt. They don't go into detail on HOW to tighten the belt.

Getting at the front and the back side of the bolts is darn near impossible, let alone if I have to pry with a bar (what would even be safe to pry on?) to set the tension. Is there a trick to getting the tension set correctly? I fiddled with it a bit but I couldn't seem to get less than 1/2" of slack in the old belt. The Haynes manual calls for 3/8" slack. Is it easier to do this from under the car or from above? I was trying to get to everything from above, but my sway bar was right in the way.

Summary:
-Is there a tension adjuster on the alternator? or do I need to pry on it with something?
-Is it easier to tension the belt from above or below?
- Are there any tricks to doing this myself without having a helper?

Thanks!
Eric

P.S. Stay tuned for next week's episode where I'll probably damage something else beyond repair and need more advice.
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1980 924 NA, US model
1987 924S, US model

Eric P · Joined: 21 Jun 2017 Posts: 175 Location: NY, USA

As promised in my other thread about the fuel distributor sealant, here is a picture I took this past Sunday. It has a bunch of quirks, but I love it.

On second thought, I probably should have just made a thread about the car and kept all the issues in one place. Sorry =(
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1980 924 NA, US model
1987 924S, US model

morghen · Joined: 21 Jan 2005 Posts: 9095 Location: Romania

Cool looking 924, 5lug and all. Nice color...not so many like this.
Hows the interior?
There was one guy mad about finding a 924 in that color...but i think he was looking for a 931.
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Supercharger and EFI kits
https://www.the924.com

Paul · Posted: Thu Jun 29, 2017 5:35 am Post subject:

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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: Thu Jun 29, 2017 5:36 am Post subject:

Part 19 provides the adjustment. Pull or pry the alternator away from the block. Part 10 causes a lot of loose belts as it ages....

Also make sure the ground wire (part 45) from the alternator to the block is present and clean.
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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.

Eric P · Joined: 21 Jun 2017 Posts: 175 Location: NY, USA

The interior could be better. It has quite a bit of sun damage, which is strange for a car that was originally sold in Ohio and then kept in upstate NY. The seats are torn, the dash is cracked, and the brown carpet in the trunk has faded to an aqua color. Other than that, it's really clean. It appears to have been stored inside as there really isn't any rust anywhere. Eventually I'd like to restore the interior, but just keeping it on the road has proven to be a difficult task at the moment. I made it a whole 487 miles this week before I had the charging system failure. That's way up from the week before where I only got 10 miles out of my fuel distributor before it started spraying fuel. The fuel distributor fix ended up being to reassemble it with a thicker layer of Indian head shellac if anyone ends up reading this.

Thank you for the insight Paul. It looks like I'm just going to have to struggle with it more to get the belt tight. I assumed there would be an adjustment bolt or turnbuckle or something to push the alternator away from the block but it appears I was wrong. Maybe it's time to fab one up or maybe just pony up and find a friend who is willing to help.

Thanks again,
Eric
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1980 924 NA, US model
1987 924S, US model

Eric P · Joined: 21 Jun 2017 Posts: 175 Location: NY, USA

I just wanted to follow up with the results of what I ran into.

I read on here that everything could be done from underneath if you remove the skid plate from underneath. That's 80% correct as the top alternator mount is a pain to get to from either side but definitely easier from the top unless you have tiny tiny hands.

Anyway, I couldn't get my belt tight enough. I believe the belt was stretched out. Once underneath I was able to conclude that my adjustment slot was maxed out. Definitely time for a new belt. In addition to that, I had a broken engine support bracket. The top of the bracket broke off at the alternator top mount. When the support snapped, it took the ground strap with it. Half my ground strap was MIA. The other half was badly corroded.

I could have possibly just replaced the ground strap but I figured as long as I was in there and a remanufactured alternator was only $65, I might as well swap it out and only do it once.

My other problem (surprise surprise) was the alternator mounting bushings. one was missing with the metal spacer and all. The other one had turned into the consistency of chewing gum. I machined a couple of "top hat" shaped aluminum spacers to fit in the alternator mount holes and hold the alternator securely in place. Not only does this make the alternator line up much better, but it also acts as a second grounding point. I guess time will tell if hard mounting the alternator will break the metal bracket or something. For the life of me, I can't figure out why it was rubber mounted. Maybe engine vibrations?

With the new mounts and belt, I actually had a difficult time mounting the new belt because it felt too tight. It'll probably stretch out after a while, but it for sure isn't slipping anymore. At any rate, my battery is charging again. Now to take it to a shop to swap out my tires and get it inspected... I wish I could do it myself. This thing is a pleasure to work on after fighting with my Pontiac Grand Prix for years.
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1980 924 NA, US model
1987 924S, US model