1977 Chevy C10 known as SharkBite

[77ChevySharkBite]

Originally Posted by knomadd

I'm by no means an expert, or even "very knowledgeable" about carburetors, but I believe that you have to press the accelerator about a quarter to half way down, once, to allow the choke flap to close on it's own. Maybe not, but mine won't engage the choke if I don't press down on the accelerator before cranking. Once it fires, the electricity will heat up a spring inside the choke cup that will allow the choke flap to open fully when the accelerator is applied again (usually a quick tap is all it takes).

Mine will fire to about 2,000 RPM, I'll tap the accelerator lightly to bring it down some (usually about 1,000-1,500 RPM) until I'm ready to go. If you're idling at 500 RPM in Park or Neutral, you're too low. Adjust your idle screw so you're at 700-900 in Park. This should put you between 500 and 700 RPM in gear. I don't like to see idle anywhere below 500 RPM as I think it starts to work too hard to keep running.

As for it dying... I'll have to think about that a little more. Not sure exactly, but if you can give me a little more info, it might help. I know you've got an edelbrock. Is it a 650cfm straight out of the box, or did you modify it at all? Was the electric choke on it or did you add it? Where are you running the red and black choke wires? How does it run/drive in other scenarios... meaning if you drive it a while, park somewhere then come out and fire it within about 10 minutes, does it fire right away or crank for a while?

When you say idle for 5-7 minutes, is the choke activated or not?

Cool thanks Duane.

Usually when I crank it I'll just turn the key until it cranks, but yesterday when it wouldn't crank I pushed down a little on the gas and cranked right up so I'm thinking that's what I'll continue to do.

Yeah when it cranks it'll go to about 1500-2000 max and once I give it a press it'll idle down and keep running. Okay well I'll adjust that tonight if I get the chance to crank it up.

It's a 600cfm out of the box no adjustments to it at all. Only thing I've messed with is my idle screw. It's an electric choke so it came that way, my choke wires black the black wire is connected on the little housing the little black housing that's on there did that advised by the Edelbrock DVD I got with the carb, the red wire is actually connected into the heater box, as that's only on when the truck is on. Driving it runs fine no skips runs on a dime. After I ran it for a little while last night it cranked pretty much on the turn of a key. As far as running it for a little bit then let it sit about 10 minutes only done that once and when I went to crank it, it cranked for a couple seconds then fired up.

The fuel pump is working fine, I was going to start messing with the air/fuel mixture screws but I think until I have a better understanding of what's going on I'll hold off on that.

[knomadd]

I should probably mention that the idle RPM I suggested is for when the engine is warm. The choke might hold slightly closed until it reaches a warmer temp, like say 150 degrees (I'm guessing here) so it's best to make sure the engine is at operating temp (whatever your thermostat is set for...185 degrees?) before you make your final idle speed adjustment.

Check your timing to make sure it's where it should be. I bet you did that already, but it can't hurt to verify that it's still good. If the timing is off and you adjust it, you may need to adjust your idle rpm again. Pull back on the accelerator lever a couple times and let it settle before you check your RPM to be sure everything is sitting where it would normally. Just turning the screw and checking RPM isn't very accurate, it'll get you close, but sometimes it will change when you're driving because the accelerator linkage wasn't sitting normally after an adjustment.

OH, and if you have A/C (sorry, I can't remember) you'll want to bump your idle speed up to about 1,000 RPM in park. In gear you should be about 700-900 RPM so when the compressor kicks in, the idle will drop about 150-300 RPM

[77ChevySharkBite]

The thermostat I have is a 190-195.

Yeah I messed with that a little yesterday and where I have it sounds like it's exactly where it should be, but I know that can throw things off too cause I noticed when you turned it so much the idle would go higher. The accelerator lever is on the top right hand corner of the carb correct?

Yeah I had a/c but was told it didn't work so I pulled it off.

[knomadd]

The "accelerator lever" as I called it is the thing the linkage you just replaced connects to. Drivers side, looks brass. Not sure the exact name, so I apologize if my terminology is confusing.

If you don't have the A/C compressor installed, then don't worry about adjusting your idle speed for it.

Are you adjusting timing by sound or with a timing gun (a.k.a. timing light) and a manual that tells you what it should be?

[77ChevySharkBite]

I'm trying to post a picture of what I'm thinking is the accelerator lever can you tell me if I'm thinking of the same thing or if not could you circle it for me please sir. What i'm thinking your talking about is in red. So it's not working anyway possible I could have your e-mail address or something and e-mail the picture to you?

Okay cool

I'm just adjusting it by sound and also where it sat before I started taking it apart.

[77ChevySharkBite]

Hey Duane I was thinking you called it the accelerator lever could you be thinking of the accelerator pump?


Also I think I may have figured out my issue, I'll have to check it out when I get home tonight or tomorrow. My distributor vacuum isn't in the right port I think, I think I have a manifold port and a timed port mixed up! so I'm going to swap those around maybe tonight and never know might solve all the issues I'm having.

[knomadd]

This is what I was calling the accelerator lever.

[knomadd]

Holley calls this the "throttle lever"... guess I was close.

[77ChevySharkBite]

Yeah I would say it's close enough for me too.

I think I have my vacuums mixed up and that's what is causing my problems minus probably having it timed exactly right. So I'm going to try and hook up the vacuums correctly and heck for all I know might solve all my issues.

[Sodell]

Yea, you need to put a timing gun on it or you will be going around in circles. Sounds like you have it adjusted OK, but timing will affect start up when cold and when hot. If your timing is off a bit it may crank hard when warm ect...I would not mess with the carb other than the idle screw, they are pretty good right out of the box, you can mess one up easily if you are not familiar with the procedure.

[77ChevySharkBite]

Originally Posted by Sodell

Yea, you need to put a timing gun on it or you will be going around in circles. Sounds like you have it adjusted OK, but timing will affect start up when cold and when hot. If your timing is off a bit it may crank hard when warm ect...I would not mess with the carb other than the idle screw, they are pretty good right out of the box, you can mess one up easily if you are not familiar with the procedure.

Yeah I'm going to get my vacuum lines/hoses connected to the right spots tonight, and then try to get a timing gun on it to see where I'm at.

So far I've really only adjusted the idle screw as that's what I'm comfortable doing. Yeah I really am not too familiar with carbs and i rather not mess one up personally

[UPNADM]

Originally Posted by 77ChevySharkBite

Yeah I'm going to get my vacuum lines/hoses connected to the right spots tonight, and then try to get a timing gun on it to see where I'm at.

So far I've really only adjusted the idle screw as that's what I'm comfortable doing. Yeah I really am not too familiar with carbs and i rather not mess one up personally

If you can't get your hands on a timing gun, get a buddy to come over, put the truck in gear and give it some throttle and put a little load on it. Then adjust your distributor until you find the sweet spot, tighten up and try it then.

[77ChevySharkBite]

Originally Posted by UPNADM

If you can't get your hands on a timing gun, get a buddy to come over, put the truck in gear and give it some throttle and put a little load on it. Then adjust your distributor until you find the sweet spot, tighten up and try it then.

Thanks man! I appreciate that.

I have the timing gun at my house that's a buddies but my only issue and maybe I need to search it but I don't know what correct timing is on a chevy 350.

[Sodell]

Start by setting it at 8 deg, after the engine is warm. Unplug the vac to the advance and plug it up before timing. Then go back and set idle. You can tweak it a little after that.

If you have a piece of chalk, you can put some in the line makes it a bit easier to see.

When you were talking about the idle going up when you turned the dizzy, that is when you are advancing the timing. retard it and the idle will go down.

[Sodell]

Korwin, you may know most of this, but here is a great video on timing. It is a little long but full of good info. You can also clearly see where he has the vac advance hooked up on the Edelbrock carb.

How To Set Ignition Timing - YouTube

[knomadd]

Sodell is correct with 8 degrees BTDC, or at least that's what it says in a 1972 service manual for a 350 auto. I just happen to have a scanned copy of that manual at work

[77ChevySharkBite]

Originally Posted by Sodell

Start by setting it at 8 deg, after the engine is warm. Unplug the vac to the advance and plug it up before timing. Then go back and set idle. You can tweak it a little after that.

If you have a piece of chalk, you can put some in the line makes it a bit easier to see.

When you were talking about the idle going up when you turned the dizzy, that is when you are advancing the timing. retard it and the idle will go down.

Originally Posted by Sodell

Korwin, you may know most of this, but here is a great video on timing. It is a little long but full of good info. You can also clearly see where he has the vac advance hooked up on the Edelbrock carb.

How To Set Ignition Timing - YouTube

It's actually funny you posted this I had been looking at some other websites and that's what I saw that most everyone was putting there's at was 8 degrees

It's funny about the video I'm not even lying I had just watched it about 5 minutes ago literally because it looked good and indeed it was very informative and knowledgeable for me.

Originally Posted by knomadd

Sodell is correct with 8 degrees BTDC, or at least that's what it says in a 1972 service manual for a 350 auto. I just happen to have a scanned copy of that manual at work

Nice Duane!! So I'm assuming that it was a generic deal then.

If I haven't ever told y'all enough thanks for all the help!! You guys rock!!!

[knomadd]

Nope, definitely not generic... Well, this was the 71 manual. I also have a 72.

[77ChevySharkBite]

okay so I have another question there's a intake manifold vacuum that's on the intake if I plug that up will it hurt the truck any? or is it just something that I can plug?

I was going to plug it back up because that's how it was originally. I understand the fact that it might not matter but just curious.

[knomadd]

You're better off plugging it if you aren't using it for a vacuum source, like for brakes. If you leave it open, it becomes a huge vacuum leak... more problems.

[77ChevySharkBite]

Okay so correct me if I'm right or wrong should I have the truck warmed up to try and adjust my timing or can I just crank it up get it idling normal and then start setting the timing?

[Sodell]

It has to be warmed up...just drive it around for a bit before

[77ChevySharkBite]

Originally Posted by Sodell

It has to be warmed up...just drive it around for a bit before

Thanks Scott!!


Well my buddy 67 c10 guy is coming over and were going to try and get this timing jazz set so wish me luck and I'll report back later

[77ChevySharkBite]

So I'm glad I'm finding this out now apparently the PO didn't know really about timing cause the timing has always been at 0 so me and 67 c10 guy are going to fix that now.

[77ChevySharkBite]

So the truck is running beautifully and better than EVER!!! The PO apparently had no idea what they were doing it was ridiculous they were 1 tooth counterclockwise off and they were running at least 20 degrees advance is what we guess they also had scratched into the balancer what they thought might have been the correct line, so that's solved so the truck just loves sitting at 0 tdc so that's what we're going to stay with tomorrow if I can I'll get some test runs in