1986 Chevy c10 stalls in gear until warm (even on hot mornings)

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Ricko1966

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Disconnect and plug the vacuum advance,set your timing at 18,drive it around no vacuum advance listen for ping.
 

Ricko1966

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18 was a stab in the dark because many aftermarket distributors have 18 degrees centrifical,and 36 total is a pretty good guess as to where your total needs to be. See if you can find out brand,model etc. On the distributor. I want to get the tim8ng roughed in so we can get the carburetor dialed in then see if you truly have a problem.
 
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SirRobyn0

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@Davidj You have already received plenty of good advice, but I'd like to provide you with this link as an example.
>>>> https://www.gmsquarebody.com/threads/how-a-carbureted-engine-should-start-and-run-cold.36845/ <<<<
In that video you'll see my truck cold start, one pump on the gas, in gear and driving within seconds of starting. My point is there shouldn't be the need for more than a few second post start before putting it in gear and driving off.

I will say that you really need a tach of some sort. The ear is notoriously not that accurate.
 

Davidj

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18 was a stab in the dark because many aftermarket distributors have 18 degrees centrifical,and 36 total is a pretty good guess as to where your total needs to be. See if you can find out brand,model etc. On the distributor. I want to get the tim8ng roughed in so we can get the carburetor dialed in then see if you truly have a problem.
Okay will do! After messing around with it today (taking the pics, checking the advance and replacing both door jamb switches to find out someone had installed a single post bulb in the cargo light…) i took it for a spin and I did notice some pinging near wot so I brought it back down to about 12° initial with the vacuum advance on the metering block. This cleared it up but still idles a bit rough on the start although I did notice the coolant lines and just general heat from the engine bay reduced. Maybe I had it a little too lean with 18-19° plus vac advance. But I’ll give it a go with 18° minus advance and plugged. I’ll take a closer look at the distributor aswell to get you a model.
 

Davidj

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@Davidj You have already received plenty of good advice, but I'd like to provide you with this link as an example.
>>>> https://www.gmsquarebody.com/threads/how-a-carbureted-engine-should-start-and-run-cold.36845/ <<<<
In that video you'll see my truck cold start, one pump on the gas, in gear and driving within seconds of starting. My point is there shouldn't be the need for more than a few second post start before putting it in gear and driving off.

I will say that you really need a tach of some sort. The ear is notoriously not that accurate.
Thanks for the vid! That’s exactly what I’m hoping for! If it’s already warm, that’s about how it goes. Except for the priming. If it’s warmed up I can just turn the key and she starts and drives. I’m definitely getting a tach. I wonder if they make one that fits the clock “gauge” in the cluster with little modification. I really want to keep the interior as close to stock looking as I can.
 

Ricko1966

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Setting up a distributor you need to find the correct initial and centrifugal first. That's referred to as total,that can't accurately be figured with vac advance connected. Knowing what distributor you have would be a big help but short of that we are going to try 18. If it pings try14. Post results I am guessing as to what that dist has in it 18-22 but I'm guessing.
 
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Ricko1966

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Read this 2 or 3 times get an understanding of it. I don't know if those links work but this should give the knowledge of where we are trying to go.
 

Davidj

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Well, I did the vac advance to full vacuum test and brought it back down to 12° initial, tinkered with the idle mixture screws a little to make her clean up a bit also did an oil change. Was quite a bit low. Didn’t realize how much she burned during this process. and wouldn’t ya know the next morning, and the morning after, and this morning, I was able to hop in er and go. Like a BEAUT! Not sure if maybe something was blocking the vac advance… Or the holley just wanted a better mix… Or the oil being low made her grumpy…. But she’s happy far as I can tell. So I spent my Saturday off whining up the wheels, gave her some wax, and she’s shining bright now! I think it’s taken care of for now. Still not sure exactly what did it, but… it did. Lol! Thank for all the help!! (It just rained when I took this pic just now so some of the cleaner I used is coming out from behind the chrome.)
 

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Davidj

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Hey! Didn't I say oil change back there a ways?
Like , a couple pages?
I’m not sure, but I was under the impression since I just changed the oil like 3 months prior that the oil would be fine. But it was indeed about 1.5-2 quarts low. When I had the manifold cover off, the rods were spitting oil just fine though so it never occurred to me it was low. I guess when I was messing around with the mixture it burned more than I expected. Since then though, I’ve had absolutely no issues starting it up in the morning and it runs perfectly. Only issue now is the oil pressure seems to hang out around 20 no matter how much I give her the beans. At WOT she might get up to 30 but seems low no? Next oil change I’ll drop the pan and see if the pick up tube is still in place. Hopefully it’s not a pain to drop it. I’ve heard stories of people having to remove the engine just to drop the pan.
 

Trucksareforwork

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Thanks for the vid! That’s exactly what I’m hoping for! If it’s already warm, that’s about how it goes. Except for the priming. If it’s warmed up I can just turn the key and she starts and drives. I’m definitely getting a tach. I wonder if they make one that fits the clock “gauge” in the cluster with little modification. I really want to keep the interior as close to stock looking as I can.
This is probably way too late but the thread just got bumped and I read it. One thing: you say “priming” when it comes to pressing the gas pedal before starting. I figured I would offer some advice in case you didn’t know:

Pressing the gas pedal before starting a cold, carbureted motor actually is all about setting the choke. It may give a shot of fuel to prime it, but most importantly it sets the choke for a cold start. Like @SirRobyn0 i made a cold start vid a while back on my 85. Icy conditions.

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Never accept poor cold starts on a stock-ish truck. These trucks were designed to start and drive in almost any conditions. Now, high performance cams with low vacuum are often dogs when cold, different story.
 

Ricko1966

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I’m not sure, but I was under the impression since I just changed the oil like 3 months prior that the oil would be fine. But it was indeed about 1.5-2 quarts low. When I had the manifold cover off, the rods were spitting oil just fine though so it never occurred to me it was low. I guess when I was messing around with the mixture it burned more than I expected. Since then though, I’ve had absolutely no issues starting it up in the morning and it runs perfectly. Only issue now is the oil pressure seems to hang out around 20 no matter how much I give her the beans. At WOT she might get up to 30 but seems low no? Next oil change I’ll drop the pan and see if the pick up tube is still in place. Hopefully it’s not a pain to drop it. I’ve heard stories of people having to remove the engine just to drop the pan.
Oil pressure should be in the vicinity of 10lbs per 1000 rpm. The factory gauge and sender aren't really accurate,put a mechanical gauge on it and verify you actually have a problem. I would buy you m9ney there is no problem with your pump pickup.
 

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