Time for a new HEI?
 

'69 K10, 327, has had an HEI in it for quite a few years. The distributor was used when I got it, and it has served well for many years.

Two years ago, the truck started giving me intermittent problems---running rough and hesitating at various times, sometimes coming off idle but sometimes on the road at speed. The problem would go away for a while, and the truck would run like a top. Then it would come back.

Last year, while I had the radiator out for replacement, I went through the ignition system and replaced the plugs, wires, cap, rotor, coil, and module. At first, everything was fine, and I thought I had cured the problem. But then I'd get a sort of a blip in the smooth purr--just like, for an instant, the engine wasn't running. This happened just once or twice on a 20-minute trip to town, with varied speeds from <20mph over gravel to >60mph on the interstate. As time went on, the "blip" would occur more frequently, and, every now and again, there'd be a backfire out the tailpipes. Now, the "blips" happen frequently and the backfires are beginning to become more frequent,
too.

Based on all this, I think I have an ignition problem. Nothing has changed about fuel delivery (Carter/Edelbrock 1405, IIRC). I suspect the old distributor is worn out. I am looking for suggestions for replacements. I would prefer not to spend much more than $200, less if possible (the $600 radiator really hit the truck budget!).

I could swap the point unit back in--I still have it all these years later, and it should be OK, but, of course, it has who-knows-how-many-miles on it, too. And I'd have to undo the mods I made to use the HEI.

I assume that verifying 12 volts at the distributor (again) would be a good idea, but, assuming the power is there (as it was the last time I checked), should I go with a stocker or look at an aftermarket unit?

What's your experience?

Re: Time for a new HEI?
 

i put a small cap generic brand with external coil on a 65 vette 3 1/2 years ago with a tach drive and it has worked fine. i think it was around $200 then, no tack drive should be in the price range you're wanting. look them up on e-bay.

Re: Time for a new HEI?
 

Check the pickup wires for continuity. The flexing when the distributor advance moves will eventually break the wire(s). Since you appear to have changed everything else, that what I would suspect. If it's bad, you have to take the distributor shaft out to replace it. These last very well. I've only ever replaced one.

Re: Time for a new HEI?
 

theswapmeetparts is the seller i bought thru, they have complete kits for under $200. wires, coil, distributor, everything. only thing i changed was the advance springs to the lighter set (3 sets were included.

Re: Time for a new HEI?
 

Maybe disconnect your tach lead from the HEI to make sure it's not grounding out somewhere.

Last June my new GM HEI started giving me problems after only a year or so of use. I first tried a new coil and module from my local Advance Auto Parts, but the new module was suspect after the truck died a couple of times unexpectedly but would fire up after sitting for a minute or two. A Davis Unified Ignition (DUI) coil and module fixed me up.

Re: Time for a new HEI?
 

I've been running an Accel 59107 HEI for over 10 years and never a problem. The 59107 is an "OEM Replacement" HEI and it's price is right in your dollar range.

Re: Time for a new HEI?
 

I had the same issues and thought it must be the HEI so I replaced my cheap MSD StreetFire HEI unit with the more expensive MSD Pro Billet HEI. I changed the plugs at the same time thinking they were fouled up from lack of ignition. Truck ran fine after the HEI & plug swap but the truck started hesitating and back firing from the tailpipe a couple days later. Turned out the intake manifold gasket was leaking and allowing air & oil to be sucked into a couple of the cylinders. I replaced the intake manifold gaskets and the problem was solved.

Turned out the intermittent hesitation and backfiring was caused when oil would foul the plug causing a cylinder to miss. The non-combusted fuel would then ignite in the exhaust causing a loud backfire out the tailpipe.

This is a common issue with vortec heads & performance intake manifolds. The paper gasket Edlebrock recommends does not seal well. The steel framed rubber gasket made by Fel-pro solved the issue.

Re: Time for a new HEI?
 

Thanks for all the input, guys. It'll be a while before I can do anything, so I am open to any and all ideas.

Interesting issue with the intake gaskets. Maybe an excuse to go back to a stock intake . . . . Gotta pull the distributor anyway.

Re: Time for a new HEI?
 

I started my truck for the first time in a couple months recently, and it backfired a couple times. I let it idle for about 15-20 seconds and then goosed it and it did it again. Upon checking it out, I found a loose wire at the bulkhead connector for the HEI. I replaced the male Packard terminal and all is well again. Never had that happen from a loose power wire before.

Re: Time for a new HEI?
 

Been running the same one for almost 22 yrs on mine. no issues at all..