924Board.org

wombat · Posted: Sat Aug 02, 2008 8:36 pm Post subject: Alternator belt issues

I retensioned the alternator belt yesterday after replacing it and not being 100% happy with the tension. Then I left the car sit for a day without doing anything to it and now it wont start?? is it just that the extra tension has put my timing out or do I have another issue?? I have been out all day thinking if it is timing or not then just thought I would ask before I did anything because it was running fantastic just proir to this.
_________________
1977 924 2.0 Auto

924RACR · Posted: Sat Aug 02, 2008 10:27 pm Post subject:

That's another issue.
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

wombat · Posted: Sat Aug 02, 2008 10:53 pm Post subject:

yeap, just went to check, first crank it started breifly then stumbled out, then nothing. It was fine before I took it out for a drive the other night got it back and went to diagnose a rattle I had found which was in the timing cover which I fixed then I retensioned the belt let it sit the night and now nothing. I am thinking fuel delivery I will go and pull a fuel line see what happens, any other ideas.
_________________
1977 924 2.0 Auto

Smoothie · Posted: Sun Aug 03, 2008 2:04 am Post subject:

Check the wiring connections to the battery and alternator, including alternator grounding.
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

wombat · Posted: Sun Aug 03, 2008 5:07 pm Post subject:

I will check fuel delivery and spark soon but have to get these headlights working first.
_________________
1977 924 2.0 Auto

Mike924 · Joined: 12 Aug 2004 Posts: 2601 Location: IoW UK

wombat · Posted: Sun Aug 03, 2008 11:19 pm Post subject:

OK I will recap.

1:- I serviced it and got the timing perfect new plugs new filters new belts etc.

2:- I noticed that the alternator belt was not as tight as i would like or that hayns recommended but i left it because i had put the bottom cover back and had to go to bed

3:- I took it out for a drive to check things before I retensioned the belt and noticed that there was a ratle coming from somewhere in the engine bay

4:- upon inspection i noticed that the timing cover grommets were stuffed and so I replaced them retensioned the belt and put back the cover.

5:- went to start to see if this had fixed the rattle and couldnt get it started so I went to bed again

6:- came back the next day and got it breifly running before it stumbled out

7:- checked that fuel was coming out of the line on the engine side of the fuel filter before the fuel distributor and checked for a spark by pulling #4 wire and seeing if it sparked against a ground point which it did also checked the alternator and battery wires which looked ok upon a visual inspection.

Now I am stuck where to next?

Also my headlight motor is blowing fuse 6 every time it is plugged but it appeared to function correctly on a bench test this may be unrelated but i figured i should include it just incase they are linked.

One more I noticed a while ago that the vac advance tube was not plugged into the inlet from the dissy this is still not plugged but can be easily enough however it has not been plugged since I have owned this car and was running well before so I doubt this has anything to do with it.
_________________
1977 924 2.0 Auto

Tiny · Joined: 10 Apr 2006 Posts: 502 Location: London, UK

hi wombat,

so you've got a good consistent spark, and timings good....you need to check fuel at the injectors on demand.

pop the injectors, and place them in clear containers.
jumper the fuel relay across pins 30 an 87.
remove the rubber boot from the top of the air metering plate.
switch on the ignition, and you'll hear the fuel pump run.
manually activate the air metering plate and you should see fuel from the injectors.

if all thats ok, its possibly a vacuum leak - check all rubber boots/hoses for fitting and splits. then check/test your aav (auxiliary air valve) as per haynes.

let us know how you get on.
regards
tiny
_________________
*****1981 - 924 - Auto - London, UK******

Ozzie · Posted: Mon Aug 04, 2008 4:07 pm Post subject:

As tiny said but I lift the plate by removing the air filter and pushing up from underneath.
(its easier)
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

wombat · Posted: Mon Aug 04, 2008 8:51 pm Post subject:

thanks guys for this did this series of checks and it turned out to be a vac leak. the large rubber boot over the plate had a vac line running into it and it was torn from a previous repair, i cut the torn part off and plugged the vac line back in a volia it started and ran like a dream, i did discover that i need a new cam belt tensioner which i sort of already knew. thanks again.
_________________
1977 924 2.0 Auto