I've had a bunch of parts hanging around for my 71, that I haven't had the time to install. Today our car got back from the paint shop (cheap paint job, but it looks so much better) and my brother (half owner of the car) took it upon himself to install my new Demon carb. This is cool, because he seldom works on the car, but also a problem because he doesn't know much about what he's doing. Anyway, I came out halfway through the process to help him, and there were a couple of things that I couldn't remember (I would have checked them during disassembly, but I wasn't there for that). First...the vaccume advance on the distributor goes to one of the vaccume ports on the carb. But does it go to one that is on all the time, or one that comes on after you open the throttle, or something else? I use to know this, but haven't worked on one of these in a while. Second...can you clamp braided stainless hose (the real kind, not the fake sheath stuff) with a hose clamp, or do you need to use proper fittings? The stainless exterior seems like it resists the clamping effort of the hose clamp, but with a lot of tightening it seemed to be on ok. Third, my brother pulled off the fuel line going from the pump (standard mechanical pump) to the carb. When he did this, a lot of fuel poured out of the pump. Later on, when the job was done, (I wasn't around) he tried to start the car, and it wouldn't start. He figured that he simply needed to crank it untill the fuel got up the line to the carb. But the battery when dead before this happened. Does the fuel pump need to be primed for it to work? Since most of the fuel drained out of it, it might just not have been working at all. If it does need to be primed, how do you do it. Thanks for any help anyone can offer.

 

Hmmm, my advice. Buy out your brother's share in the car. Keep all tools out of his hands and keep him away from the car before he destroys it. Good intentions aside, you're right he doesn't know what he's doing!

You should use the proper connectors for braided hose. If you don't they will surely leak, at the least it looks like crap.

 

A mechanical fuel pump should auto-prime on a Corvette as the pump is the lowest part of the system. The fuel should gravity feed into the pump inlet from the tank...at least it did on mine when I replaced the fuel pump.

Also, use the correct fittings for the braided hose.

 

How long has the car been sitting and did it run when you put it there? The vacuum line should hook up to the port that has no vacuum at idol. The fuel pump doesn't need priming, is there any gas left in the tank? Fuel pumps can stop working if the arm is stuck in the down position; you will need to take it out to check for that. Remember to plug any vacuum ports that you don't use.

 

The vacuum advance should go to the "timed" vacuum port, on that does not have vacuum at idle but does when you open the throttle.
Yes you can clamp stainless lines. It is just a ruber hose with a wire wrap on the outside, even the "real" kind not the "sheath stuff". I have some here at the house where the wire wrap is not bonded to the hose and it came is from Aeroquip. I recommend you get some heat shrink tubing to cover the end of the hose before you clamp. Without it the wires will unwrap, poke you in the finger and make you bleed and cuss. It is prefered if you use rubber hose / stainless w/ hose clamps that you push the hose on to either a barbed fitting or over a flared fitting. That way the hose can not just slide off.

Fuel pump does not need to be "primed". I do recommend that you fill the float bowls of the carb with fuel so it will start right away. Do this by carefully poring fuel into the vents of each bowl. Don't do too much or it will over run into the engine. Get a better battery too. I did not even prime my carb and on the new engine it only cranked for about 10 seconds before the bowls were full enough to start the car.



[Modified by BSeery, 11:20 AM 10/25/2001]

 

Scott -
Check out our Demon installation over on the C1/C2 site:
http://forums.corvetteforum.com/zerothread?id=170591

This was done with no hoseclamps - it's all hard-plumbed into the Demon-supplied inlet hose assembly. I'm putting together an article on how to build this fuel line, and I'll post it on the Forum as soon as I get it all together. I don't trust rubber line and hose clamps on the pressure side of the system at all, and highly recommend running real steel line with screw-on connections everywhere. If you want one of these hard lines with the in-line screw-on filters, I can build one for you (assuming you have the same type Demon inlet line).

The fuel pump is self-priming, but when all the gas ran out of it, you lost a lot of fuel in the line. Plus, it sounds like you didn't prime the carb: you want to pour a couple of "shots" of fuel directly down the vent tubes of the float bowls. This will give the carb enough gas that the engine will fire and run long enough for the fuel pump to start doing its thing.

Run your vac advance off the ported source. On the Demon, there are two vac outlets side-by-side in the throttle plate on the passenger side, just under the primary bowl. Use the forward one of the two - this is ported vacuum. The other one is manifold vacuum.

 

Thanks everyone for the feedback. It's running now, but I haven't gotten a chance to take it out, we discovered that one of the bolts in the rag joint was missing. I got new stainless bolts the other day, but I've been so busy that I haven't had a chance to go put them in. I also got a new throttle pedal from Lokar, as the one we have in there is real junk. It bends so much that it will hardly open the throttle all the way. Thanks again for all the info. Much appreciation here.

Scott