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240 Carbed 240, Only 2 Cylinders Firing?

I also found an old TB thread where someone said with confidence that you must use spark plug wires which are intended for vehicles with points. Vehicles without points run on electronics, which must be shielded from the high voltage noise from the spark plug lines.
Just to keep focused on what does what...some people get the idea that they have to run solid wires to get the "best" spark. These things are only used on muscle cars, and usually by racers who don't understand how high voltage works. Any car with electronics of any kind should have a set of suppression wires to prevent interference with the ECU (if one exists) and with your radio, etc. These wires are also polite to other drivers who are on the road near you. Suppression wires, resistor plugs (common) and rotors with resistance built in (common) do NOT sacrifice your potentially 'hot' spark for the sake of interference. High voltage does not act like 12 volts d.c. from your battery. The exact resistance values aren't really important, but might let you know if the coil is open or shorted, etc. I still can't understand how a bad condenser would make only 2 cylinders fire, and the same 2 cylinders at that! That part is across the points in order to keep them from arcing and wearing out prematurely. If points are pitted badly enough to prevent the coil from firing, you would see the giant pits in the points contacts. Well, back in the points/condenser days you always replaced these parts together, and the stock condenser assumes you have the stock coil - they work together to make the best spark...at the plugs!
-A final note: what used to be standard wires was a thin paper strip covered with carbon granules (conductive) and wrapped in a rubber jacket. These wires actually wear out in a few years or become intermittent. On the other hand, you are wasting your money by spending hundreds of dollars on 10mm pink silicone spark wires. Both will work fine when new, with the carbon wires wimping out after a few years.
-L

-L
 
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Thank you,

Yeah, the saga continues. When the mechanic left a message last night reporting that he had "got it started", he didn't mean running well. And then when they began working on it today to get it running well, they had the no-start condition surface again. So I don't believe it is the condenser after all. They have triple checked the timing right back to the timing belt. Last I checked they were checking to see if the points were opening far enough. (I had checked them previously and found them to be 0.016", and free of pitting/carbon)
 
That point gap is too narrow. That will cause too much dwell time and take away potential spark energy from the system. The gap is supposed to be .020". The gap you measured is what a VW Type I uses. The spec for the spark plug wires from Volvo for the suppression type wires is 500 ohms per foot. The earlier 240s used resistor ends on the plugs and on the ends that go into the distributor cap. So those older models used non resistor plugs. Once Volvo changed to resistor spark plugs in the 80s. Then the wires used non resistor connectors. There is also a suppression resistor in the rotor. So even if you ran non resistor plugs you still have some suppression.

The latest and greatest spark plug wire setup is the mag core wires which use a spiral wound metal conductor around a fiberglass core. This provides excellent suppression while maximizing spark energy. You can buy these for your car from Rock Auto and other parts suppliers. Just be sure that the wires read mag core instead of carbon suppressor core. They last a bit longer than the carbon core wires in my experience.

Your coil has a resistance spec in the green books. A points system will usually have about 3.5 ohms in the primary and a typical secondary measurement is 9500ohm+/-1k. If you have a ballasted type coil then the primary is usually around 1.8-2 ohms.
 
thank you all for your input.

After another 8 hours of two Volvo specialized mechanics (and another on the phone who "has been a Volvo mechanic since this 1982 was new on the lot"), they've got it back up and running. Even they admitted that they were unsure of what the silver bullet was that fixed it for certain. But they claimed that the timing belt was off by several teeth (which is strange because it drove fine on the weekend), they cleaned up a lot of the connections - but I think the kicker was swapping the points. Either we were getting leakage past the isolator plate in the bottom, or the points were too close, or the points were in rough shape (again, checked, seemed fine).

Anyhow, paid them $700 tax and parts in - they only charged me for 4.5 hours. The trick with this one was getting it running because it was in this movie this morning. And they delivered.

After the purchase price of $1300, that puts me at a total of $2000 and a lot of my time. I'd say it's not the end of the world for a manual 1982 wagon. Yes, it suffers from some surface rust on the fenders - but that will be resolved after the movie.
 
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