JQuillin

I picked up an old 80 4x4 with a 22r and 5speed a few weeks ago. It was running great till about 2 days ago when it completely died in the parking lot at work. Truck would turn over but not light off. So after a few hrs of trouble shooting and between the interweb, '83 FSM, and Chiltons library, I figured out the igniter was bad. So I picked up a GM module and coil, made up a few new wires and presto. I have ignition once again.....however.

The truck doesnt want to start unless you hold in the gas a little... Once started you still have to keep in the gas a little or it stalls/chugs out and mists gas back out the carb with a hiss. It revs fine but once the gas peddle is released and the RPM drops to idle it stalls or chugs. The carb apears to be aftermarket, possibly a Weber as it has the square choke plates, but its grimy and I havent looked for identification markings yet.

Im wondering if the GM module is having issues the pickup signal as it retards to a lower RPM and not giving enough spark, or possibly the idle RPM might need adjusting on the carb. Could it be a timing issue with the chain slacking and throwing the dizzy ignition timing off a little?

Jason

83

Well once you start modifying things it's really hard to say.

I will say that checking the timing, cleaning and tuning the carb is never a bad idea. When I buy a vehicle I always do a full tuneup. Distributer cap, rotor, plugs and wires, valve adjustment, timing.

Co_94_PU

iTrader: (-1)

The ignitor either fires the coil or it doesn't. But that coil could be not fully saturated in which case yes, considering it's likely meant to fire twice as fast on v8 that's pretty unlikely the coils fault either..

go over your wiring, clean firm and large power connectors, make sure you get as much battery voltage to them as you can. Don't forget your ignition switch has to carry that load also and it's old and tired..

JQuillin

I went ahead and picked up another pickup coil, just in case. Found out one of the guys I'm stationed with knows carbs and has some experience with 20r and 22r's.

In the FSM is says something about inspection of the "breaker plate" what function does that have in the timing?

Co_94_PU

iTrader: (-1)

Breaker plate, point breaker plate.. my books aren't old enough to cover that inspection, need photos of that page if you want it translated from engineering speak.

Generally it's going to be along the lines of it's not floppy sloppy and oriented correct.

JQuillin

Was able to fiddle around with the truck some more today to no avail. So the vacuum advance closest to the dizzy is no good. Checked timing was firing around 9-10 BTDC so i adjusted it back to 5 btdc. Cleaned the outside of the carb up to get an idea of what it its. Its stamped R7343.. which after googling shows to be a Holley 5200. Possibly off a mid 70s 2.3L.