i need a copy of lars are someones help on tuning my qjet on my 77 please!!!!!!!!!!!!!!!!!! i cant get it to quit white smoking i think there is a problem with the chock not sure though im a carb roockie any help would be greatly appreciated

 

Smoking white would mean that you are getting to much air. Are you sure that you do not have a antifreeze leak into the cylinders. Does the smoke have a sweet smell to it? Does the smoke go away when you rev the engine ? Sticking chock would cause darkto black smoke.

 

its suppose to be a new motor thats just been sitting the guy i bought the vette from just never finished the resto. but i havent smelled anything sweet i pulled the plugs they had a little oil on them smelled a little like gas i figure the oil is from just sitting idiling i start it from time to time but the interior is in pieces so i dont drive it. i dont know how to adjust the carb but ive tried i can get the smoking to go away some but not all. the motor is suppose to be new with no miles on it just started to pull in and out of the garage. thanks again

 

http://corvettefaq.com/engine.asp

The above site at corvettefaq has the Lars papers.
:seeya

 

Gas (too rich) smoke is BLACK, White or blue-ish smoke is oil, Coolant or water is like steam and disipates very quickly.

 

Your carb won't make you smoke white. You have some other engine problem - you're either burning oil or antifreeze if you're blowing white smoke. Pull your spark plugs out and take a look at them all - the offending cylinder should have a plug that's wet.

Drop me an e-mail if you'd like a copy of the latest revisions to the Q-Jet papers - they have been revised and updated since being posted in the tech section here on the Forum.
V8FastCars@msn.com

 

Just a thought...

I don't know if you have an auto or not, but there were a couple of threads a while back talking about trans fluid getting sucked up into the manifold through the modulator line.

 

jerryp -
That's correct - a ruptured modulator diaphragm will cause ATF to be sucked into the intake manifold, resulting in white smoke. To test for this condition, simply unplug the tranny modulator line from the carb and see if tranny fluid is in the line. If not, suck on the line and verify that there is no leak in the modulator - it should hold vacuum. If there is no fluid in the line, and the line holds vacuum when you suck on it, the modulator is usually good, and the white smoke problem is engine-related.

 

i pulled all the lines off the carb and checked for trans fluid none. after playing with it all day it seems that the smoke is more of a greyish blue (light) i pulled the plugs they were all caboned up (new plugs yesterday) the # 2 plug was alittle moist not to bad though what should i do next HELP PLEASE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

The line for the modulator comes up from behind the engine and attaches to the back of the intake manifold.

I don't know if mine is all stock or not, but it attaches to the modulator (at the trans) via a small section of rubber hose, comes up between the firewall and the engine as a hard line, then attaches to a plastic nipple at the intake manifold with another small section of rubber hose.

Let me know if you can't find it, I'll try to scan a picture from the AIM.

 

If you're blowing grey/blue smoke out the tailpipes and your plugs are black, you have an oil consumption problem. There are a few possibilities for where this is coming from:

1. Your intake manifold may not be sealed up well. If the engine builder did not use intake gasket sealer compound, it is possible for SBC manifolds to have a vacuum leak in the block valley area, and this will suck oil and oil fumes right into the intake runners. This is difficult to diagnose and troubleshoot. If you think it's a possibility, best bet is to just yank the intake off. Check it for flatness and sealing to the heads after it's off, and then assemble it using good quality gaskets sealed with the Edelbrock Intake Gasket Sealant (part number 9300).

2. Your heads may not have been assembled well, resulting in the engine sucking oil down the intake valve guides. If the smoking is worst when the engine has been shut down and sitting for 30 minutes, it's usually because oil is dripping down the valve guides. Also, if you let up on the gas pedal and coast (pulling a bunch of intake vacuum) and then get back on the gas and see a big puff of smoke, it's usually oil coming down the valve guides. However, an intake leak will cause the same symptom.

3. Your rings may not have seated. If the engine is fairly new, it may not have been broken in properly. Rings require that the engine be placed under heavy load very soon after initial start-up. Many people think that a new engine has to be "baby'ed", and this is the worst thing you can do for the rings - they will never seat. If the smoking is worse when you get on it, the oil is coming from bad rings/failure to seat. You can test for this by unplugging your PCV valve and observing the valve cover breather vent: if oil smoke is puffing out the breather vent with the PCV disconnected, you have a ring blowby problem. If you detect this, fill your crankcase with straight 30W oil (not synthetic) and take the car out and put multiple hard runs on it at wide open throttle through 1st & 2nd gear. This may force the rings to seat against the cylinder walls.

 

ok lars i will check these things out thank you & every body else for your help!!!!!!!!!