Quick HEI Cap question

[Baradium]

The Cap to my HEI has that plug that goes from the dizzy body....

There are three wires and they connectors in that plug. BUT there are only two connectors in the cap, it looks like the center one is missing.

Is this a neccesary wire and the connector fell out or is it uncessary and the cap just doesn't have one? I don't want to put it all together just to find it doesn't work or worse yet mess up any electronics because of a missing connector....

Thanks,
Ryan

[RussTburb]

I think one is for power to HEI, one is for TACH and the other I think is for a ground but i might be mistaken, also I do not think there is a wire that hooks up to it. Just an internal ground for the coil body. Somebody corect me if I'm wrong.

[Baradium]

Wrong plug....


I have two connectors where the 12V keyed power comes in, one is that 12V power... next to it there is a plug for the tach... there is no other plug there.

Then there is another plug from the disitributor body, it is right next to the aforementioned keyed power/tach part. It has three wires and three contacts inside it.

This plug is the one I'm talking about. There are only contacts in the cap for two of those three wires. The other one appears to be missing, the question is whether it's supposed to be missing or fell out...

is this a little clearer?

Thanks,
Ryan

[old Rusty C10]

the distributor expert i know of here is CROSSY hes usually on the 73-87 boards but im sure hed answer a question if ya email him or pm him hes a decent guy but i did go out into my garage and look at the HEI GM distributor ihave and there s one set of wires on the distributor that goes to the cap these wires are three of them and they attach behind or closert to the cap body than the IGN one and the TACH one. there are three plug ins in this attachment and inside the cap is three prongs to attach the plug to . I didnt take it apart to see where the three wires go to in the cap but if memory serves me correct the left and right ones are to the coil inside the cap and the center is a ground from the side of the coil it sits in the cap and is attached to the bottom of the coil via one of the screws that holds the coil into the cap
Post again if ya want me to take this apart and all
Bob

[Baradium]

Originally posted by old Rusty C10
the distributor expert i know of here is CROSSY hes usually on the 73-87 boards but im sure hed answer a question if ya email him or pm him hes a decent guy but i did go out into my garage and look at the HEI GM distributor ihave and there s one set of wires on the distributor that goes to the cap these wires are three of them and they attach behind or closert to the cap body than the IGN one and the TACH one. there are three plug ins in this attachment and inside the cap is three prongs to attach the plug to . I didnt take it apart to see where the three wires go to in the cap but if memory serves me correct the left and right ones are to the coil inside the cap and the center is a ground from the side of the coil it sits in the cap and is attached to the bottom of the coil via one of the screws that holds the coil into the cap
Post again if ya want me to take this apart and all
Bob

Thanks a lot!

If you think it might help to take it apart, I'd appreciate it, but if I can get the answers I need otherwise I guess it doesn't really matter. Basically, I need to know whether I need a new cap because of that missing center prong. If it's *supposed* to be there and isn't just something that some caps don't have, I'm going to guess that it is something I do need. What do you think?

Your memory matches what the cap seems to say on it. Unfortunately, it's thanksgiving day so no parts store will be open for me to go to. I'm a little short in the time department, I go back to TN sunday so I'd like to get everything fixed tomorrow. I'd be a little less nervous if I could take the '70 up there with just the HEI done but it doesn't have heat, so it can't go to TN until I can get a new heater core for it. The scout has a brake hose that is about to burst so I'm not moving that more than around the yard until I replace that hose, fortunately the scout stuff should be a bit more straight forward.

If the cap isn't a big deal and it'll still work correctly without that center prong, then I could go ahead and install the HEI in the chevy now and know it's done and ready for daily use again today, but I don't want to even put it in until I have everything set up how it needs to be. Running bad with the points is a lot better than not running at all.

Hopefully once I get this cap issue resolved the swap will be fairly straight forward... on the semi bright side, if the cap does need to be replaced, I might as well get a new coil to go with it (if they don't already have one), which would mean a hopefully good spare coil at least...

Thanks,
Ryan

[jhow66]

Baradium the center prong is a ground for the coil.It is a metal piece that is bent to fit under the coil where the screws go. Will not run without this. Must have fell out when the coil was out of cap. You probley will have to get one out of a old dist. as I don't think they sell them by their self.

[Baradium]

Originally posted by jhow66
Baradium the center prong is a ground for the coil.It is a metal piece that is bent to fit under the coil where the screws go. Will not run without this. Must have fell out when the coil was out of cap. You probley will have to get one out of a old dist. as I don't think they sell them by their self.

So I need either to find/make one or get a new cap/coil etc?

How much would a new cap and coil run me? Anyone know?

Could probobly get by with just a new cap, but if I'm going to get a cap, might as well get a coil, and rotor too...

Thanks,
Ryan

[jhow66]

Baradium I was wrong--they do sell the groung strap. If your present cap, rotor and coil are good just go to Autozone and ask for part # GS1 (I looked it up under 1976 Chevy 2wd 350 PU). It cost all of $.99 + tax. Just take the coil cover off and you will see how it goes.

[Solver]

Are you talking about a distributor like this with the extra three wire plug?

[Tx Firefighter]

No, that's a "Spark Control" disrtributor off a little later truck. My 83 came stock with one of those. He means the earlier style without the 4 wire plug.

[Baradium]

Originally posted by Tx Firefighter
No, that's a "Spark Control" disrtributor off a little later truck. My 83 came stock with one of those. He means the earlier style without the 4 wire plug.

What he said...


I found out at the parts store I could get the ground strap, but I got excited and bought a new cap, rotor, vacuum advance (advanced was bad too), coil *and* the ground straps while I was there, didn't get a new covor but I can put the old stuff in a plastic bag, figure it can be a spare setup to keep under the seat. After dealing with the scout's prestolite, where modules list for $200, $40 for all that new was a bit more than I could take...

Going to try to install it today, wish me luck!

[Baradium]

having some issues with the HEI, still troubleshooting the thing going to come back to it tomorrow (today?)

[Baradium]

Finally got the thing fixed, went ahead and got a new dizzy body while I was doing everything now. After putting the new body in, used a timing light to set it to TDC and then it fired right up.