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1986c10 09-29-2018 10:35 AM

No spark
 
Hey guys, havent been on the forum in a very long time. Just picked up another c10, its a 1979 and is a 95% done project but they werent very wire savvy. The engine is fresh but has never been fired and the guy knew no details about it. It appears to be a .030" over 327 with some bolt ons. I got it to crank but it wont fire up, it acted like it wanted to but I didnt want to crank a fresh engine too much. I adjusted the float height (it was spraying fuel) and fixed 3 seperate fuel leaks. Then I decided to verify distributor timing, found that the distributor was 180 out, I restabbed it, now i have no spark. I have 12v to the "batt" wire at the distributor. I took apart the distributor and found that the seconday resistance was ol, bought a new coil and resistance is now in spec. Still no spark! I'm going to add an additional ground from the engine to the frame because the current grounds suck. Any other thoughts on how I could not have spark? Or what I could have messed up as it did almost fire before so it must have had spark. Thanks in advance!

lutronjim 09-29-2018 10:20 PM

Re: No spark
 
I would think if the starter winds up good you must have a pretty good ground to block.

Don't know how you measured the 12v to coil but you can have 12v on a meter and not have hardly any amps. Might see if wire can light a high wattage bulb,

1986c10 09-30-2018 10:37 AM

Re: No spark
 
They just didnt ground the engine directly to the frame which usually is how I would do it. I added another just to be sure, no change of course haha. I ended up returning the coil I bought and purchased a new MSD distributor, after setting the engine on fire due to an additional fuel leak and timing being off, i finally got it started! Somehow the distributor went bad. I hope to set the timing, adjust the carb and break the thing in (engine was built in 1998 and never fired).

Dead Parrot 10-01-2018 03:40 PM

Re: No spark
 
Stock engine grounding on this era truck was usually a strap from the back passenger valve cover bolt to a stud on the cab and the battery negative goes to a bolt w/star washer on the alt bracket.

Sometimes folks paint the place where the dizzy hold down Y clamps and that can cause poor grounds. Assuming they installed the gasket on the bottom, the only ground left is through the camshaft gear and oil makes a fairly good insulator.

LH Lead-Foot 10-12-2018 01:55 PM

Re: No spark
 
Sorry if I am not familiar with what distributor is on a 1979 truck...it is HEI with carb?
The most common mistake made with HEI distributors is two items;
#1 leaving the old rubber insulator in the cap or coil bottom, then bolting it on. This breaks the center post.
#2 The coil is grounded thru a stamped metal strap, placed under the coil and exits in the connector housing. This is where the module connector plugs in and goes to housing ground inside.
#3 Thumbs up on the painted bolt, clamp or block where the distributor drops in.
#4 Remove connectors, cap, rotor and carefully un-plug the pick-up trigger coils two wire connector. Insert the proper terminals and plug into a DMM with it set to ohms.... Now, using a pair of needle nose pliers, wiggle each wire without moving the connector. Note that reading should not move. The wire can break inside the soft silicone covering and cause no input to ignition module. It should measure between 500 to 1500 ohms, depending on model and temperature.
Best of luck.


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