Distributor woes

[porcha42]

Great weekend warriors of the world hear my need! I have a 71, 1.6, 914. I need to know what a good or bad distributor looks like. How do I test my distributor? What do you look for in a good distributor? I think this is the source of my rough idling, sometimes it even stalls. When it stalls, it is very difficult to start. Please advise.

[Dave at Pelican Parts]

Well, first off it's probably a 1.7, not a 1.6. The smallest stock Type IV I've heard of is 1679cc, which is referred to as "1.7".

There are a bunch of things to examine when you check your distributor. In addition to obvious things like timing and dwell (and do they change erratically with RPM), you check to see if the points are pitted or worn away. You check to see if the ground strap from the points plate to the distributor body is connected. You wiggle the distributor shaft to check for play. You look at the cap and rotor to see if they have any pitting, buildup of "stuff", etc. Examine the spark itself by taping a spark plug so that its end is in contact with the engine case or fan shroud, then crank the motor. Spark should be fat and white.

If the distributor passes those checks, your whole ignition system is likely in good shape. Start checking the fuel system. Carbs if you have those, FI if you have that.

There are lots of notes on this forum about checking out your FI system. Fewer on carbs, probably because lots of people seem to think they're really simple and bulletproof. For a good comprehensive article on FI, check Kjell Nelin's D-jet guide on the 914 Fan Page, under Tech Refs. http://www.914fan.net

Good luck!

--DD

[porcha42]

Thanks Dave, I'm a big fan. I have new plugs, wires, cap, rotor, adjusted the dwell, but having a big problem timing the car. Equipped with a new timing light, adjusted it according to the mark, rough running, retard it, rough running, advance, rough running, had to play by ear. I think the distributor is not adjusting. Either that or the coil is gone. Thanks.

[Porsche914]

I havent worked on Porsches yet.. I do however build up motors for cars, and i find alot of time rough idle can also be due to a vacuum leak... take a can of Carb cleaner and spray around the engine to see if it speeds up or dies...

this is just a helping idea...

[ChrisG]

Do you have the stock FI fitted?

Another thing to check (with it being a 1.7) is the Vacuume Advance pump - I dont know if it is called that, however that is what I call it

It is a cylidrical object with 4 wires attached to it and a long hose going to the FI main body.

I have found that if the hose is broken or cracked, it can cause the engine to run terrible. Also check the connections in the engine bay.
Looking on the back top of the crank case, you will find a bunch of earthing point. Again, if these are not earthing to the case, they will cause all sorts of oddball problems.

Chris G