Idle Problems

[78Eliminator]

So I was having issues making my 454 idle.
Last night I slapped the carb back on and it wouldn't idle. So I got another carb I had laying around and I couldn't make it idle with that one either.
So I put the original one back on and I did three things and I am not sure which one fixed it...
1. I had the alternator exciter wire disconnected so it wasn't charging, and I hooked it up to make it charge.
2. I advanced the timing a little.
3. I hosed down the intake manifold seams with WD-40.
It would idle indefinately for several minutes so I think it's working..... I guess the test now is to blow off all the wd-40 with compressed air and see if it still idles. When I would blip the throttle it would backfire. Wondering if my timing is off or of I'm lean.
J

[flat broke]

Justin,
I would bet on timing. Without going and looking at the specs for the cam you are now using, I'd bet your initial advance was insuficient to provide enough vacum signal to properly operate the idle circuit. Out of curiosity, how much advance did you have before and after you changed the timing? I found on my cam I needed 16-18 degrees initial to get a halfway decent idle. Every engine is different, so you have to experiment. I would think that if it was an intake leak, it wouldn't idle without the constant presence of the wd40 you used for leak testing.
Good luck, and get us some pics of the lil' green monster. I'll be curious to hear how that Drake pump works out.
Chris
[ September 17, 2003, 10:20 AM: Message edited by: flat broke ]

[78Eliminator]

flat broke:
Justin,
I would bet on timing. Without going and looking at the specs for the cam you are now using, I'd bet your initial advance was insuficient to provide enough vacum signal to operate the idle circuit. Out of curiosity, how much advance did you have before and after you changed the timing? I found on my cam I needed 16-18 degrees initial to get a halfway decent idle. Every engine is different, so you have to experiment. I would think that if it was an intake leak, it wouldn't idle without the constant presence of the wd40 you used for leak testing.
Good luck, and get us some pics of the lil' green monster. I'll be curious to hear how that Drake pump works out.
Chris I think (and I hope) that you're right. My initial was 10 degrees. I decided to bring it up to 15, then I hooked up the alternater and it brought it to life. But, when I blip the throttle it backfires. Perhaps I need to advance even more?

[flat broke]

how rough or smooth is the motor idling and at what RPM with the 15 degrees? Do you know the advance curve for the distributor? Are you sure all of your plug wires are on the correct cylinder? Just check the simple stuff and I'll bet you get closer. What carb are you running now, and what are the particulars (jetting, squirters, etc>) not that I'll be able to give you the right answer, but the more info you have on the boards, the more likely you are to get quality replies that are pertinent to your setup.
Chris

[78Eliminator]

flat broke:
What carb are you running now, and what are the particulars (jetting, squirters, etc>) not that I'll be able to give you the right answer, but the more info you have on the boards, the more likely you are to get quality replies that are pertinent to your setup.
Chris Well, it was getting late last night so I quit working after I got it set at 15 degrees. I think I am going to advance it a little more. It was idling a little rough, but sounded great when I nailed the throttle. I have a holley 850, but when I looked up the actual holley part number, it turns out it's an 830. I have all four idle screws out three turns. All four jets are holley 78s. That's as far as I have got with my limited window to work before the neghbors want to shoot me.
J

[Hustler]

Justin wht dist. are you running the carb sounds like it is set up right unless you have a blown power valve but I'm not sure that would make it back fire while not under a load.

[78Eliminator]

Hustler:
Justin wht dist. are you running the carb sounds like it is set up right unless you have a blown power valve but I'm not sure that would make it back fire while not under a load. It's a jacobs ignition and dist.

[Hustler]

78Eliminator:
Hustler:
Justin wht dist. are you running the carb sounds like it is set up right unless you have a blown power valve but I'm not sure that would make it back fire while not under a load. It's a jacobs ignition and dist. So it's electronic then? How old is it?

[78Eliminator]

Hustler:
So it's electronic then? How old is it? I don't think it's electronic. It is just the distributer with the integrated coil that is mounted on the top of the distributer cap kind of dealeo.

[Hustler]

Sounds like an electronic. Have you looked under the cap? the reason I ask is that cam you are running does not need more 15* of timing. the electronic module in the distributer could be bad or maybe a cap and rotor would help.

[Blown 472]

or maybe the weights are stuck, does it advance?

[Hustler]

Blown 472:
or maybe the weights are stuck, does it advance? Thats also possible. when was the last time you used the dist.? What is your total advance? have you checked that?
[ September 17, 2003, 12:01 PM: Message edited by: Hustler ]

[LeE ss13]

You're in San Diego and you have an 830...... hhmmmm ... I think you really need an 850, sooo, I-tell-you-what-I'm-gonna-do .... I'll trade you a fresh 850 for your 830, why? Because that's just me and we are only allowed up to an 830 in Super Stock. We will be racing at BayFair in Mission Bay SD this weekend. Stop by. Anyway, does the engine respond or change rpm when you adjust each idle circuit. If all is correct, each idle screw should be 1 1/2 to 2 turns out from bottom. If not, get the engine to idle where you like, shut if off and remove the carb. Flip it over and drain all the fuel and see how far the throttle plates are open. No more than 1/3 of the idle transfer slot should be exposed. If too much is exposed, the idle circuits are being bypassed. The correction is to drill a 1/8th hole in each throttle plate. If the plates are more closed and none of the idle slot is exposed, there is an air leak some where. My $.02

[Hotcrusader76]

Just to add to the above...
Justin we've gone over this a few times before. Set the primary idle speed screw (referencing to the transition slot) so exactly 0.030"-0.045" is exposed. Now on an 830 this is going to look weird because the throttlebody actually bevels inward vice being parellel to the venturi. Once that has been done leave it. Don't touch it.
Now in order to get a correct idle without messing with the primary butterflys is to switch to adjusting only the amount of opening on the secondaries. Yes drilling will also help but isn't required. Normally drilling is required for motors with not enough carburetor (for a lack of better words) and most of the time when your duration is above 280+ advertised. Obviously not your case
Does your 830 have an adjustable secondary from the top? Or is it the stock versions where you need to flip it over to turn it? Either way, those billet baseplates you have can donate the piece you need to adjust them.
Good luck. If this is adjusted correctly and you still have problems look into the float height, fuel pressure, and or ignition system.
~Ty
[ September 17, 2003, 12:13 PM: Message edited by: Hotcrusader76 ]

[Blown 472]

Not enough carb??? what bout two 850's??

[78Eliminator]

Ok, thanks guys. I am out 3 turns on all four idle screws. Maybe now that it does idle, I will turn them back in and see if I can still get it to live...

[21rayson]

three turns on a four corner idle carb sounds like a lot too me.sounds like you have a vac leak. just my opinion.

[Hotcrusader76]

three turns out is fully open with the amount of taper on a needle. One turn out is nominal.

[gnarley]

Justin, you never did say.... WHAT THE RPM IS that you timed it at? Could you be 15* @ 1200 or something like that, and whats the total? If so I'd say you need more timing. If you are down around 600-800 RPM then 15 might be about as much as you need. Let the engine tell you what it needs & limit your total accordingly, set an idle speed then your mixture & then finish with your idle speed. Sometimes I go back & forth several times to get the idle set.
Also that 830 is a bitchen carb keep it! I have one on mine & love it. The only thing done to it was boost referencing by 058, other than that it works like a charm!

[78Eliminator]

gnarley:
Justin, you never did say.... WHAT THE RPM IS that you timed it at? Could you be 15* @ 1200 or something like that, and whats the total? That's the thing dude, I was doing this in my driveway with a cold motor. I think the rpms were around 1000. I didn't get too far because it got too late and I didn;t want to piss of the neighbors. Today I brought the boat with me to work and I'm going top take it to the local lake (San Vicente) at 2pm. I'll let you guys know what happens and if I get it sorted out.
Thanks to ALL of you for chiming in. There are some good fellas on this board and days like this make all the flame wars seem insignifigant! :D

[1FastHallett]

I HAD THE SAME PROBLEM WITH MY 454 WHEN I FIRST PUT IT TOGETHER. I HAD A 850 HOLEY ON AN OLDS MOTOR WHEN I GOT THE BOAT. I BLEW IT UP ON THE 3RD WEEKEND OUT AND BUILT A NICE 454 WITH A DECENT SIZE CAM. HAD THE SAME PROBLEM. I GOT TIRED OF DEALING WITH IT AND JUNKED THE HOLEY AND PUT AN 850 SPEED DEMON ON IT. BEST 500 I HAVE SPENT ON THAT MOTOR. ALL I HAD TO DO WAS SET THE 4 CORNERS AND IT WAS ALL GOOD. THE SPEEED DEMON HAS LARGER AIR BLEEDS FOR MORE AIR FLOW AT IDLE. THATS WHAT I HAVE BEEN TOLD ANYWAY.

[78Eliminator]

Well folks I got her to run perfect today. But damn, that boat is a little slow compared to my 500 lb. daytona hull. No matter, I hammered through chop that would make my fillings rattle loose in the daytona. Anyway, thanks for all your help. You are now talking to a fellow that has a running boat. Kinda.
I used a cheap bolt for the alt and it snapped in half so I need to fix that. Also the jet leaks a little so I need to seal that up. When I got back tonight I rubbed the trailer against a cinderblock and made a trailer tire flat. Hell, **** yeah. Mo money, mo money.
Anyway, I am and will be down with all the up comming trips and next summer. You will be seeing my mug now. Whether you like it or not!!!!!
You know, when I put this Schiada together, I told myself that I would not mess with it. That I would just let it be a cruiser.....but damn, it only spins 4500 rpms, I KNOW I can squeeze a couple ponies out of her. Here I go again.........
[ September 18, 2003, 09:53 PM: Message edited by: 78Eliminator ]

[Blown 472]

That is great, just leave it a booze cruiser and build a kick ass motor for the tunnel boat.

[78Eliminator]

Blown 472:
That is great, just leave it a booze cruiser and build a kick ass motor for the tunnel boat. That's what I'm thinking.....