Help - 1986 Silverado won't start

[jimmerock]

Hey gang - new member here. Have a problem with my truck.

1986 Chev Silverado 305 700R4

History: Last summer my brother borrowed it. It stalled on him at the mall. Couldn't start it. Let it sit for 30 mins, started fine and drove home. This carried on for a while, occasionally stalling and then not starting for a while until it was left alone (presumably while the fuel evaporated as it was flooded???), yet when it was running it seemed to run fine. Eventually one day it just wouldn't start. I didn't have a chance to fix it before the long cold winter set in so it sat in my driveway until now. It has:
- New sparkplugs
- New rotor and distributor cap
- New Ignition coil
- Newer starter
- New battery
- New fuel pump

I think it is a fuel problem because:
(a) Almost all the electical parts are new
(b) I was able to start it up no problemo when I tried to start it for the first time this year. I let it run in my driveway for ~10 minutes and then it died on its own and I was unable to start it again.

I'm looking for some help since I can't afford to take it to the shop and my wife is tired of it just sitting there. I need to get this thing going so I can use it for various summer projects.

When it's running, it seems to run like a top.

It seems like a carb problem to me but I'm wondering if there are any other ideas???

(I also tried carb cleaner to no avail). Someone told me it could be old fuel but I poured a bunch of fresh stuff in and it made no difference.

When I try to start it, it turns over strong but just keeps turning over and over and over and doesn't even cough or sputter or even TRY to start.

Any help would be greatly appreciated.

[Lt.Del]

my thought is fuel float level....either the float is stuck, or the needle it pushes up and down, allowng fuel in the carb as needed, is stuck.

Also, I have had similar problems with one of those electrical gadgets in the distriburot, when the engine got warm, it woudn't start.    Let it cool, it started no problem.

when it doesnt start, does it get spark?

[dirtmod0]

ignition module will do that.

[Lt.Del]

yep dirtmod, that's the gadget in the distributor i was meaning to type, but couldn't come up with the  name of it.  It did that to my 79 and drove me crazy 'til i replaced the whole darn distributor.....and it was new at the time. Let her cool down, she started right up.

[Marc]

Had this exact problem with a Mazda B2000 once.  the top of the fuel tank was rusted out, the inside was rusty. It'd run for 10 or 15 minutes and then die...wait a while and it would go for a while a gain.  Turns out it would run and draw fuel until the sock filter would plug solid and stall...when it sat the dirt would "fall away" from the sock and it would get its fuel againand run again.  Pull the fuel filler hose off and siphon the fuel out and see how clean it is.  Check the filter in the carb too...

[VileZambonie]

Check the distributor pick up coil first. If it won't start right now, ohm it out. Report your readings here.

[TexasRed]

Sounds like the ESC took a dump. I'd just replace it with an ebay unit or maybe a reman'ed unit for like a '78 from the autoparts store.

[Irish_Alley]

like vile said pick-up coil, since your in there you might as well replace the icm they both run i think under 20 buck at autozone. you just have to pull the distributor and remove the cap, then remove the pin in the gear and slide out the shaft then replace pick-up coil looks like a star and it surrounds the shaft and the icm its the little black box rectangle thingy. mine did the same thing b4 and it was the coil. you can have them tested i know you can have the pick-up coil and coil pack tested at autozone

[Cowman85]

perhaps bad gas/dirty tank bottom or fuel filter?

[VileZambonie]

The pick up coil is surrounded by a permanent magnet. There is a coil of wire called the pick up coil around it with two leads. When the reluctor on the distributor pole piece passes the apex an ac voltage is induced into the pick up coil. that signal is sent to the ignition module to induce spark. When they go bad the circuit opens and you lose spark. They get worse when they heat up. Check this first.

Here's an example of how to replace it if it's bad.

http://forum.73-87chevytrucks.com/smforum/index.php?topic=11105.15

[fitz]

I'd agree with Vile on the pick up coil. They are cheap money and an easy fix. If you check for a spark keep in mind that sometimes a bad pick up coil will still produce a weak spark.
I ran into that problem years ago with a 350 that would not start. It was getting a spark and fuel so it drove me crazy trying to solve the problem. It turned out the spark just wasn't strong enough. It fired right up with a new pick up coil.

[exilous]

my buddy had that problem in his 76 chevy it turned out to be a bad module in his distributor after we changed nearly everything else around it.