Hitting a brick wall

[Jakes-66-K10]

Well, after spending the entire summer by myself underneath this '70 CST/20 I'm about ready to give up. Yeah, it's that bad... I've installed a new GM crate engine and countless parts to complete it, a 700r4 and all of BowTieOverdrives kits (wiring, TV etc), a new driveline, new exhaust, new instrument cluster, and it seems the truck is so close, yet I am totally stuck now.

I have done the initial timing, as far as raising #1 to TDC putting the dizzy in, wiring - everything is done. But this thing runs like CRAP, needle on the tach bounces 500 rpm and it just does NOT want to run. Exhaust is so heavy it fills my entire yard, so I can only try and run this engine for a minute or two before the fumes are too great. Problem is, I can't tune the carb because the engine runs so poorly.

I went out and bought a timing light to try and get it timed, so I can move to the next battle of tuning my carb (Road Demon) but I cannot see the mark on the balancer at all with the timing light. I thought maybe I really screwed up so I crawled underneath the truck with the light, looking if I had it 180 degrees out. For the life of me, I just can't see the mark - even after painting it dark black. When stationary the mark has high contrast... I just don't get it.

I really wish I learned more about this stuff years ago when I had someone around to teach me. Figuring this out by yourself really sucks sometimes. I'm seriously feeling like I'm in over my head - and considering selling the whole thing. But I thought I'd get some feedback from all the wisdom on this board, and give it one last shot to see if anyone has any idea how to help...

Thanks guys (and gals)

[pjmoreland]

I have two quick suggestions.

1) Check, double check and triple check that your spark plug wires are ordered 1-8-4-3-6-5-7-2 around the distributor.

2) Loosen the distributor clamp just enough to allow you to rotate the distributor by hand. Start the truck and turn the distributor by hand a little one way to see if it improves things. If it doesn't, try turning a little the other way. You might be able to get it to run just enough to allow you to use the timing light. Another thing you can do is to buy a timing mark tape that wraps all the way around the outside of the harmonic balancer that gives you marks from 0 to 360.

[Jakes-66-K10]

I will check again for the firing order, but it does "run" although not well. I had to increase my carb idle screw quite a bit to have it run by itself so I can use the timing light. This is where I'm stuck, because I can't see the mark anywhere.

[Jeepster376]

Little steps, keep at it one little tweak at a time and before you know it, it will be purring like a kitten. Sometimes when everything is just a bit out it seems like it will never be right but it will.

Paint a big bright wite stripe on your balancer grove over the black. Make sure your vacuum advance is disconnected and plugged. Make sure the idle is not too high. Forget the light at first and just start it up and turn the distributer with your hand until it sounds smooth. It will probably be too advanced at that point, but that's OK. Now take the light and stick it in there as close to the balancer as you can get (without getting it caught in the belts or fan be carefull) if you don't see the mark, turn the dist back and forth a little to see if you can find it. Hopefully this helps you to get the timing under control. Once you get it set reconnect the vacuum advance, and the idle should jump up. Readjust the idle as low as you can.

Now hook up your tach, and a vacuum guage, and adjust the air screws on the carb one at a time very slowly for maximum RPM and vacuum. You may have to make tiny tweeks and then watch the guages to see what happens, if there is no effect your idle is probably too high, lower it. When you've found maximum RPMs and vacuum, readjust the idle and repeat the air screw adjustment again. Repeat this proccess untill it's purring like a kitten.

[shifty]

Originally Posted by Jeepster376

Paint a big bright wite stripe on your balancer grove over the black.

He beat me to it - use White Out. Everybody's got some of that stuff. It works like a charm. Hell, a white glass writing pen will work.

As for the other stuff with capping vacuum advance, etc, this is a crucial step.

[Johns70]

what do you mean by heavy exhaust? is it smelling like fuel? does it seem to run better if you rev it up ?you may need to adjust the float levels on the road demon,its based on the holley. if they are to high it will make it just about inpossible to tune.

[tomatocity]

agree with the others especially SMALL STEPS.
* make sure that #1 is correct
* check for vacuum leaks and retorque the intake manifold and carburetor
* look at the spark plugs and gap them again

Is your gas tank clean? Check your fuel filter to see if there is any trash. If so the trash might be in your carb. This happened to me with a brand new Ed 1406.

Sit back and do something relaxing. Make some notes about what you have done and what it will take to complete the project. Read these emails for reference and encouragement. We have all been there. I can relate about learning early and needing a helping hand. What does Pink Floyd say "Breath Deep".

[Jakes-66-K10]

Originally Posted by Johns70

what do you mean by heavy exhaust? is it smelling like fuel? does it seem to run better if you rev it up ?you may need to adjust the float levels on the road demon,its based on the holley. if they are to high it will make it just about inpossible to tune.

I mean it's so thick it literally creates a cloud that fumes up my yard, my garage - everything. The exhaust looks very rich, but then again what do I know - it may be too lean (it's dark at the exhaust tip, but then lots of smokey grey fumes as it dissipates). So this is just adding to the problem, I know I need to tune the carb float levels and mixture, but I can't tune until I get the timing right. And it's not easy to time it when you only have a few minutes before the exhaust is so heavy you can't breathe.

Thanks for the advice, I may just take a break from the project for a while - maybe that's the deep breathe I need. I've been calling around auto repair shops too, I think it may be better to take it to someone. This way I can do the little steps, after I have it running descent. I really need to find out where "normal" is and go from there.

[tomatocity]

Nah, do it yourself. Unless you are in a huge hurry.

You should be able to see and set the timing quickly if you follow the advice that has been offered. Always use the brightest white you can get for your timing marks. Use a half mark for "0" and a full mark for your preferred timing mark. The whiteout marker is an excellent idea.

If your timing is set correctly and it still runs poorly then you need to set the fuel bowls. You know it is RICK so you need to LEAN the fuel bowls. Check the Demon webpage and see if they have technical information on how to do this statically (not running). You can always call their tech support and talk to them. If this works well enough you can finish the carb adjustment(s) and start on the other items. Little steps and a lot of patience and perserverience.

git er dun!

[panhandler62]

Do all of the static adjustments a second (fifth, whatever) time.

Check the firing order.
Check the static adjustments on the carb.
Check the static timing.
Check the cam timing -- a couple teeth out there and you'll never get it running right.

I am assuming that the Demon works just like a holley mech secondary --

Check that the fuel in the bowls is at, but not above the sight holes. Set the idle screws by lightly seating them and then backing them off about 2 1/2 turns. That won't be exact, but it should be close enough to run ok.

Get a helper to turn the motor over with the coil disconected (pull the whole cap if you have HEI) and hold the throttle wide open while looking down the carb. After the initial "squirt" there shouldn't be any visible fuel going in. If there is you have a stuck float (which some brand new carbs do have!)

Hopefull this, or something else posted here, will get you over the hump.

[magooster]

Originally Posted by panhandler62

Do all of the static adjustments a second (fifth, whatever) time.

Check the firing order.
Check the static adjustments on the carb.
Check the static timing.
Check the cam timing -- a couple teeth out there and you'll never get it running right.

I am assuming that the Demon works just like a holley mech secondary --

Check that the fuel in the bowls is at, but not above the sight holes. Set the idle screws by lightly seating them and then backing them off about 2 1/2 turns. That won't be exact, but it should be close enough to run ok.

Get a helper to turn the motor over with the coil disconected (pull the whole cap if you have HEI) and hold the throttle wide open while looking down the carb. After the initial "squirt" there shouldn't be any visible fuel going in. If there is you have a stuck float (which some brand new carbs do have!)

Hopefull this, or something else posted here, will get you over the hump.

I put a Carb, Cam and GearDrive in my '72 and it ran like sh*t and there was a ton of black smoke coming out of the tailpipes. After fouling sparkplug after sparkplug and pulling my hair out trying to tune my Speed Demon Carb it turned out my Cam was out 1 tooth. after that it ran like a dream. So I would definetly check your Cam timing even if the Timing chain was factory installed.

[Jakes-66-K10]

Anyone have any experience with the GM crate engine and warranty work? I understand it is covered for hardware and labor, wondering if it's my cam how the dealership handles this...

[VetteVet]

A couple of easy mistakes to make are to run the plug wires counter clockwise on the distributer , they should go clockwise looking down on top of the distributor. and to forget that no. 1 is the front on the drivers side. They run 1-3-5-7 on the drivers side and 2-4-6-8 on the passenger side. Not saying that you didn't know that ,but it is a possibility. I think it might be the carb too.


----------------

[Jakes-66-K10]

Whoa is that diagram correct? If it is that may be my problem because the other firing order diagrams show a sequential order on the distributor cap.

Edit: Nevermind, that looks normal now - I'll check again when I get home but I do think I have it setup this way.

[cdowns]

if there's a doubt about timing i have found over the years its a good idea to pull the dizzy out disconnect each individual spark plug wire put them all in a big pile and start by the book at square one// alot of people me included have a tendencey of when trying to visually inspect something you just keep seeing wrong as right and don't get the problem solved until complete disassembly and starting over fresh//what size carb do you have??anything more than 600 and you'll be running pretty rich out of the box

[Jakes-66-K10]

It's a Road Demon 625 vacuum secondaries and electric choke.

[bagged91]

I agree with cdowns. My motto is "If at first you don't succeed, try again". Take your time, start over and do it step by step. Sometimes, that's what it takes. My dad used to have a little running joke with me when I was building my Nova, "Now I know why they call them Chevy II's. You have to do everything twice!"

Also, if you take it to someone, you will never really know what the problem was or how to fix it.

[71meangreenc10]

Have too add that yes check the cam timing, and I have never had any luck with Holleys...or anything that looks like one, but the floats probably need set. They will flood easy. I have used Edelbrock carbs and even Quadrajets and have had little problems tuning or using them....

Smitty

[Boog]

How bout that demon with electric choke. Do you have it wired up? Or is the choke valve wired open temporarily? If that choke valve is staying fully closed it'll flood like the devil. Make much smoke!!

[72MARIO]

I also would say that the choke is on. If you have not hooked it up yet Loosen the 3 allen bolts and spin it the way the lean arrow points. That will assure you the choke is off. You can watch the front flap open up to the vertical position that where you want it untill you can set it properly. Also check to make sure your not on the exhaust stroke when the 1 piston is in the TDC position.

Good luck.

[Randy70C-10]

I'm running a Demon on my stepside, the floats were adjusted wayyy to high when I took it out of the box. I've been tuning on it for two months but I think that it's just too much carb. I've always had good luck with Holleys, the Holley Avenger on my 30 Chevy works great, I may be ordering another soon.

[tomatocity]

Boog that is why they pay you all that money! You are probably correct and we have been beating everythingelse to death. Boog for President!

[A.P.]

vortexofpain check your distributor it seems that its installed wrong. You should be able to see the timing mark on the balancer, even if your carb is not adjusted properly.
A.P.

[chickenwing]

I feel your pain. Ya feel like you have all this ability in comparison to all the non-moterheads you know and then you run into this. I had a very similar experiance to this. Turns out I was 180 out on my distributer. I was pi$$ed when I found the problem cause I had a hard time droppin in the distributer. Posted my problem and the Board came back with the how-to to make it easy. Kinda ramblin, sorry. Back to you.

Have no experiance with Holley's/Demons, prior posters have that covered anyway. Provided that is not the problem I am leaning towards timing and plugwire routing also. Bring your motor to TDC on the compression stroke. Remove #1 plug, put finger over hole and have assistant crank till you feel air blowin out. Then rotate by hand (easiest with all plugs removed) til the timing marks lines up. Pop the Dist. cap and mark on the outside of the distibuter where the rotor is pointing. Install cap, the mark you made will be plug wire #1. Then follow along clockwise in firing order 8-4-3-6-5-7-2.

If this is over-simplified, I mean no offence. Can't see what you got and don't know what your skill level is.

[Jakes-66-K10]

Thanks everyone for your help. I did quadruple check my spark wiring, and that wasn't an issue. I'm sorry to say it, but I gave up and caved in. I towed it to a shop last night, and got an update this morning.

So far, they have found the balancer I purchased for the engine is incorrect, even though I bought them both from the same GM parts desk. They are swapping out the balancer for a "notched" one. The tech explained that the mark on my balancer was not lining up with TDC even though it is lined up on the keyed part of the crankshaft. I also needed a new timing tab.

It sucks paying someone else to do work, when I have come this far. But honestly, I don't regret it - sometimes it's totally worth having someone else work on your problem. I've been chugging away on this new drivetrain for almost 4 months, and I just felt like I needed some positive things happening this far into it, ya know?

I'm scared to see the bill on this.