jerryjfunk

When we try to start the engine it seems to fire a few cylinders and then quit when I let go of the key. I'm guessing that means that there is no power getting to the distributor when the key is in the on position. What would cause this?

There is a hot wire with a loop end that I have no idea where it goes. It's a little further down the harness that goes to the distributer and windshield wiper moter. Does anyone know where this goes? Also, is there supposed to be a ground strap on the distributor?

Thanks for any help!
Jerry

69Rat

The distributor should be grounded to the block via the points ground.
:smash:

jerryjfunk

Where do I connect the ground on the distributor? It's HEI.

Pete79L82

An HEI distributor only requires the heavy red wire to be plugged into the distributor cap to run. (besides the harness plug from the base of the distributor to the cap). The heavy red wire should have voltage any time the key is turned on.

The only ground on a HEI distributor is through the distributor body where it sits in the block. There is no seperate ground wire.


[Modified by Pete79L82, 8:37 PM 8/15/2003]

jerryjfunk

Hm... Now I'm confused. I wonder what could be wrong? Maybe it isn't getting enough fuel... :confused: :confused:

Jvette73

Look down in the carb and pump the throttle and look for gas shooting from the squirters. If you see it then yur probably gettin gas. Also you'll probably smell the gas if its gettin there. Did you have the dist out? If so it might be a firing order or timing problem. Do you have a timing light? If so connect it to the ignition wires one at a time and crank the engine and pull the trigger on the light. If spark is getting to the plug wire the light will flash. Check each wire to see if all of them are flashing. The engine doesnt need to be running to get a flash from the light. also you can shoot the timing scale while cranking the engine. You should be able to see the mark on the balancer if yur timing is close. If you see no mark on the balancer then the timing is probably way off. that should be enough to get you started on trouble shooting. Post back with what you see.

jerryjfunk

We got it running... it was just that the wiring harness that goes to the started wasn't connected correctly. :crazy:

However- new problem. We got it timed right- 38 degrees before TDC at about 3,000 RPM (I'm not sure- the tach doesn't seem to be working right- does anyone know where to get a tool to plug into the dist. to see how accurate the tac is?). When we plug the vaccum hose into the vaccum advance unit, the engine immediatly quits. Any ideas here?

Thanks for all the help and advice- I hope to drive it soon!

Jerry

Jvette73

Firstr of all is this a motor with new cam and lifters? If so dont let it idle for at least 20 mins. Keep the rpms up to at least 2500 for the first 20 mins of run time, then work on the fine tuning. Have you done that yet? If so we can move on to the fine tuning.

Jvette73

Did you time the engine with the vacuum hose connected? If so go back and do it again with the hose dis-connected and plugged. If it idles with the hose connected but dies when you unhook it, it sounds like the timing is still too far retarded as a result of setting timing with hose connected.

Also there is a choice of using either ported vacuum source, which only pulls vacuum when the gas pedal is depressed, or full vacuum source which pulls vacuum at idle. if you had the engine idleing while using full vacuum source, and you had the timing too far retarded, that could explain why it might die when you unhook the hose.

BSeery

yeah - another tach !

A diagnostic / hand held tach can be plugged in there. You can buy a different tach from the parts store and temp. hook it up there, that's what I do.

jerryjfunk

We timed it with the hose dissconnected because it won't run when it's connected. I'm using one of the small ports on the carb (Holley 750). Right now we've got it advanced 36 degrees. Should we go more, or is there something else I should be looking at? I rebuilt the distributor using performance kit I bought from Jeg's... there isn't anything I could have messed up in there, right?

Thanks,
Jerry

Jvette73

what happens is....if yur dist is getting vaccum at idle it will raise the rpms. What people usually do is just drop the idle by turning the idle screw back. But then when you disconnect the hose the timing from the vacuum advance is lost and the idle drops to below a point at which it will sustain the engine running, and so the engine stalls out. When yur running full vacuum to the dist at idle, it would not be uncommon for the engine to die out after unhooking the hose.

So forget vacuum advance all togeather when timing and setting idle initially. Then decide if you want to use ported or full vacuum source. If you decide to use full vacuum, then when you hook it up the rpms will go up. Your response will be to turn back the idle screw. This could mean that it may not idle when the hose is unhooked. My recomendation is to find a ported vacuum source, one that only pulls when the throttle is opened off idle. A ported source that only works when the throttle is opened would be a port that is up higher on the carb. The ones at the base of the carb are usually full vacuum sources, which would cause an idle jump when hooked up, and therefore induce you to turn the idle screw back to the point where it wont even run if the hose is dis-connected.

I hope im not confusing you. I sometimes have trouble putting knowledge into words in a constructive manner.

Whats your lowest sustained idle speed with hose unhooked and what type of carb do you have?

jerryjfunk

Wait, hold up.

I think I might have explained the problem wrong. The engine quits when we plug the hose into the distributor. It seems to run fine when it's plugged. So that doesn't make sense- the RPM should increase when we plug it in, but instead it just dies. Could this mean that we have it too far advanced to begin with?

Oh, and we have a Holley #3310 750cfm.

Jerry


[Modified by jerryjfunk, 6:35 PM 8/16/2003]

Jvette73

So it dies when vaccum is applied. Hmmm...that is kinda wierd. Normally if you have the idle and timing set right with the hose unhooked, the idle will increase when its connected. For the momment im kinda stumped. Maybe one of the wires inside the dist under the plate has a problem with insulation or something. Then when the hose is connected the advance plate moves into a position that causes a short? hmmm scratchin my head on this one. Hopefully some others can chime in and add some other ideas.

Try this. Start the engine with the hose unhooked then connect the one end to the dist and put the other to your mouth and apply vacuum. Maybe halfway thru the motion of the plate it will raise, but at a certain point it would just die out instantly as if someone turned off the key. If so then it could be a wiring insulation problem inside the dist causing a short circut against the advance plate when it moves to a certain point. ????????

jerryjfunk

We seem to have it to working...

I was thinking that maybe we had it too far advanced. Then, once the vaccum advance kicked in, it was WAY too far and caused the engine to quit. So we retarded the timing and then hooked up the hose and tried to start it. After a couple steps we got it to start, and it seems to run fine now.

I think we ended up with a total advance of 36 degrees. We let it run at 2,500 for another 10 minutes to make sure that the cam is broken in right. Hopefully we'll be able to take it up the road tomorrow to make sure the rings seat, but we need to get the transmission cable connected, but it doesn't seem to line up (see my other post- http://forums.corvetteforum.com/zerothread?id=626992).

The motor soungs great though, it vibrates the kitchen floor! I'm just praying every time I hit the gas that it won't throw a rod or something. Scared to death. :lol:

Jerry

ps
Thanks for all the help, John!