Running Rich

[89GroundPounder]

Ok it's a 72 C10 with a 383 Stroker, it has a manual choke 600 holley and has the HEI Dist. It is getting 12.46 volts to the dist so getting the juice it needs for that. But when I start it up it has a VERY strong gas smell coming from the exhaust. I know the timing needs to be tuned in more (at 35 past TDC right now and was told closer to 46) but does anyone have any suggestions?

I have ordered the vapor canister to hook up to it since the original was toast and have the idle mixture screws at 1 1/2 turns like the manual states but it is just baffling me right now on how to fix it.

Any help is greatly appreciated.

Thanks

[rodnok1]

What is your timing set at idle with vac advance unplugged? That's the first place to start. 46 is alot of total advance for most motors. Stock HEI's do not pefrom well on higher hp motors. Are you using the choke at all at start up?
Set the idle screws as far in as you can without it stalling after you set the timing.

[89GroundPounder]

The timing right now is 35 with advance hooked up. The dist is a stock one with performance guts added (module and such). Choke is wide open and 1 full turn out is the best I can get before the engine starts trying to stall out.

Will try and set the timing tonight with the vacuum disconnected and see what it'll do.

Thanks

[76bonanza]

When you say 35 with advance hooked up you mean 35 total right. Not 35 at idle.

[89GroundPounder]

I mean with the truck running at idle speed and vacuum still hooked up it's at 35.

[dznucks]

35 is suppsoed to be the max timing when you rev the motor to say 3500-4000rpms. at idle you should be somewhere between 6 and 12, give or take a few degrees depending on your set up.

that should be your problem.

however i am experiencing the same issues as you where i can't adjust the idle screws out more than 1 full turn without the engine dieing. if you still have the problem after you fix your timing, there is furhter tuning to be done inside the carb.

[ccd3]

Originally Posted by 89GroundPounder

Ok it's a 72 C10 with a 383 Stroker, it has a manual choke 600 holley and has the HEI Dist. It is getting 12.46 volts to the dist so getting the juice it needs for that. But when I start it up it has a VERY strong gas smell coming from the exhaust. I know the timing needs to be tuned in more (at 35 past TDC right now and was told closer to 46) but does anyone have any suggestions?

I have ordered the vapor canister to hook up to it since the original was toast and have the idle mixture screws at 1 1/2 turns like the manual states but it is just baffling me right now on how to fix it.

Any help is greatly appreciated.

Thanks

Did you adjust your float? Whenever the weather changes from warm to cool, I have to tweak on my float adjustment on my Holley. It's a 10-second adjustment- remove the sight plug from the side of the float bowl, use a box-end wrench and screw driver to adjust the float. if memory serves- clockwise is leaner, counter clock wise is richer.

[76bonanza]

Originally Posted by dznucks

35 is suppsoed to be the max timing when you rev the motor to say 3500-4000rpms. at idle you should be somewhere between 6 and 12, give or take a few degrees depending on your set up.

that should be your problem.

however i am experiencing the same issues as you where i can't adjust the idle screws out more than 1 full turn without the engine dieing. if you still have the problem after you fix your timing, there is furhter tuning to be done inside the carb.

And your idle screws should be turned out only as far as needed to achieve the highest vaccum at idle mine are only out 1/2 turn each there is no set amount of turns it varies per application.

[89GroundPounder]

Ok home now and just did some tuning, anything below 25 degrees the engine bogs down and tries to die, right now carb is 1/2 turn out and throttle response is great but still very strong fumes. I have a 600 manual choke holley and it doesn't have the fuel bowl adjustment on it.

Any other ideas why it might be running so rich?

Thanks for all the help

[cdowns]

do you have a stock fuel pump

[89GroundPounder]

It has a Holley 80gph fuel pump on it.

[Boog]

And a fuel pressure regulator? And set at what?

[89GroundPounder]

No regulator on it, bought a stock fuel pump new for $20 so going to give that a shot, if not it then only out $20.

[89GroundPounder]

Ok got the new stock fuel pump and installed it, helped alot but still running a little rich. Timing is set at 25 pdc (any lower and it tries to die) and carb is 1 turn out, seemed to run best at that.

Any other ideas?

[67shortie]

25* at idle?

If so, what is your idle speed and how far do you have to set the idle speed screw to keep it running? If you have a smaller cam, this will run very irratic at that timing setting. Big cam in the engine, this may be needed but even my .630 lift cam in the Chevelle only wants 15 or so to be clean at 1100.

There are a few things that will make a Holley run rich:

Excessive fuel pressure
Blown power valve
Too much initial idle adjustment cranked to keep it running (exposing the transition slot pulling in fuel from the main circuit) Check to see if turning the idle screws in until it dies. If it does not recheck everything I listed.
Idle screws cranked out to far.
Too high of a float setting, look down the carb at idle and see if there is any fuel dripping out of your boosters, if there is a power valve or float setting is amiss.

Now, on a side note, Holleys are inherent to run rich right out of the box. there is not much you can do about that except fooling witht eh bleed sizes and I would highly discourage that.