924Board.org

[924-UK]

I'm trying to double check my static timing and all spark plug cabling as the PO never got the car running correctly. It will start but will only run on 2 cylinders.

I set the crank mark and also the cam timing mark and they line up ok.
I then checked my timing mark on the flywheel.


All seems OK but my distributor doesn't seem correct?



This is based on the following diagram I saw on the forum which puts the orientation of my rotor arm completely out of alignment with cylinder 1?



Can anyone give me any pointers please.

[924RACR]

Yeah, no, the distributor position doesn't look right.

The rotor arm at TDC should be pointing to the rear most bolt on the intake manifold, and the distributor body needs to rotate so the notch on the distributor is what the rotor is also pointing at... this will put the electrical connection pointing roughly in the direction of the ignition coil.
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[924-UK]

Thank you.

I can see the small mark on the distributor - this is currently at the rear near the bulkhead and just to the right of the wiring connection. Is this the mark I need to align the rotor arm with? I'm assuming it's the actual brass contact on the rotor arm that needs to point to this?

Last time I had to do this was back in the mid 80's!

[924RACR]

Correct on all counts; so the whole distributor needs to rotate some 90 degrees (roughly) clockwise...
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[safe]

To clear up or confuse things. It doesn't really matter where your rotor points, you just have to arrange your spark plug wires to suit.

If you have crank and cam at TDC, the rotor should point on the post that is connected to cylinder 1, the next post to cylinder 3, then 4 then 2.
_________________
/Magnus, Stockholm Sweden
=======================
Porsche 924 -79 NA, EFI and Turbo.
Porsche 931 -79
Porsche 911 -77, 3.2 Targa
Porsche 911 -69, 3.6, Coupe

[morghen]

Thats right, engine must be at cyl1 TDC (crank and cam signs aligned)
Then you put in the distributor (vacuum mushroom pointing towards the outside of the car).
Then you place the rotor as it only goes in one way.
Then rotate the housing of the distributor so that the rotor is pointing at that small mark on the distributor housing.
Then take the distributor cap and place it above the distributor, make sure you see where the small mark on the housing is or where the rotor is pointing.
Then connect the cap output that is pointed by the rotor/dizzy mark to the Cyl1 spark plug. Then moving clockwise, connect the next output on the dizzy cap to the Cyl3 spark plug, then next output clockwise goes to cyl4 and the next one to Cyl2 spark plug.
Tighten the dizzy housing, put the cap on and your car should start and run fine.

After it starts you have to adjust the base timing, for that follow the procedure from the manual....or ask here and someone will respond.
_________________
https://www.the924.com

[924-UK]

Thanks for all your replies. I've made the adjustments. Plus spotted that the PO had the incorrect firing order too!

Just waiting for a new king lead for the coil as the old one disintegrated when I tried to remove it.

[924-UK]

OK, a bit of an update - after the changes I made to the distributor position and firing order it now starts fine and runs cleanly over 2k but it is still very lumpy below that and struggles to idle on a cold start (it was -4 deg C though).

I will test the voltage to the WUR and AAV next to make sure they are operating.

Whilst I was checking my vacuum pipe routing I noticed this plugged vacuum pipe!



It seems to be connected to the rubber intake boot (the bolt in the middle of the pic is one on the metering unit).

Has something been bypassed?

[morghen]

I think thats the crank vent line that normally goes from the crank breather to the intake...somebody maybe capped that off and likely left the crank case breather venting to atmosphere.

Need more pictures to confirm but that should not be an issue, unless the plugging/capping of the intake boot was done poorly or has rusted and is now a vacuum leak.
_________________
https://www.the924.com

[924RACR]

Great news! -4C is not cold! Also, your car's running better.

You're on the right path, and there's a very good chance the thing needs/wants an Italian tune-up, clear the crud out and all. Quite possible the injectors are not spraying entirely well now, too... after all that downtime...
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[924-UK]

OK, so no voltage at either AAV or WUR with ignition on. But, having been reading more forum posts about this I am getting conflicting info. One post says the 12v should be present with just ignition on, another one says only when cranking.

Which is it?

[924-UK]

[scm924s]

Always sensible to list the year of your car when asking for help, things change over the years.

The crankcase vent routing changed over time, on early cars it vented into the airbox which appears to be as you have shown. Later cars vented into the underside of the plastic inlet trunking which I imagine is what you have shown plugged, Bear in mind the US ventilation system is different to ROW cars due to their smog rules.
_________________
1984 n/a Ruby Red Metallic
1988 924S Guards red- sold
1986 924S Guards Red - sold
1984 n/a Black - sold
1980 n/a Le Mans#1 - sold
1980 n/a Le Mans#2- sold
1977 Martini - sold

[924-UK]

[scm924s]

Didn't know there was another 924 in Glos, perhaps we could meet up via here ,,,https://porsche924.co.uk/
_________________
1984 n/a Ruby Red Metallic
1988 924S Guards red- sold
1986 924S Guards Red - sold
1984 n/a Black - sold
1980 n/a Le Mans#1 - sold
1980 n/a Le Mans#2- sold
1977 Martini - sold