Quadrajet Carberator

[74 C-10 Shorty]

GM Contracted out Carter to produce the Quadrajet as Rochester could not keep up on demand.

Yes that's true, but still two different animals nothing the same about them.

[74 C-10 Shorty]

I am leaning towards weak ignition as well. Sorry it is HEI there is no ignition coil at all. I never thought of ignition problems. I was about to order a new fuel pump, but I am told these mechanical ones either work or don't work or are leaking when they are failing. HEI, Wires, Plugs? What kind of cost am I looking at? Big Money for the HEI coil I bet

Yes there is a coil, it's in the cap that's why it's bigger than a points distributor, now is this a stock factory unit?? I'm betting it is??, if I'm right that is the problem, factory units were made to go down the road at 2500 rpm for 200,000 miles not high rpm stuff and after 3500rpm they fall off, the cure is an aftermarket 50,000 volt coil and module that will give you a hot spark at any rpm no matter the load on the motor.

[Steve341]

I will go take a photo of the distributor and the Carter Quadrajet looks identical. All parts on the carter even have the same part number as the old rochester

[Steve341]

The Truck is a camper special, and I just am using it for that. There is a camper in the back surely it can go higher than 2500 RPM. So this cutting in and out has nothing to do with my tuning of the carb? The truck revs quite high with the rear end in it, geared to be a work horse not a speed demon meaning high RPM at lets say 60 mph

[Steve341]

I will go take a photo of the distributor and the Carter Quadrajet looks identical. All parts on the carter even have the same part number as the old rochester

[74 C-10 Shorty]

Oh it's possible the jetting could be off on the carb plugs will tell you that, but as you say it revs up pretty high that's because it has a 4:11 rear end gear(factory standard)and I'll guess you have about a 31" tire? that's around 3000rpm at 60 and will be ok at cruise but put a load on it at that speed and rpm increases and ignition will fall off, also the quality of the plug wires is a factor and the type plugs used, I may have missed it but did you do a complete tune up on this??.

[74 C-10 Shorty]

I will go take a photo of the distributor and the Carter Quadrajet looks identical. All parts on the carter even have the same part number as the old rochester

Looks like stock HEI, coil is is in the center on top.

[Steve341]

I don't know if it has HEI ignition or Points. The distributor is quite large and I don't see a wire in the middle going to an ignition coil. I have a sneaking suspicion I wasted my money on the carburetor I never thought of an ignition problem.

[Steve341]

Should I start with new plugs and wires? I am going to return the old carburetor tomorrow to get my $50 core back. Should I pick up a set of new plugs and wires? The previous owner said they are 10-15 years old right now.

[74 C-10 Shorty]

I don't know if it has HEI ignition or Points. The distributor is quite large and I don't see a wire in the middle going to an ignition coil. I have a sneaking suspicion I wasted my money on the carburetor I never thought of an ignition problem.

Re read my post  you have an HEI, the coil is in the distributor it is self contained, the hump on the top is the coil, all it takes is a direct 12 volt wire to the unit, BTW did you check that???..

[74 C-10 Shorty]

Should I start with new plugs and wires? I am going to return the old carburetor tomorrow to get my $50 core back. Should I pick up a set of new plugs and wires? The previous owner said they are 10-15 years old right now.

Holy crap, 10-15 years old,LOL, yeah I'd say you need a complete tune up,lol, does this goes for the distributor too?, probably could use a new cap and rotor too.... Ok gotta go, be back in the AM..

[Steve341]

Lol I will pick up a set of plugs and wires and put them on tomorrow

[74 C-10 Shorty]

Lol I will pick up a set of plugs and wires and put them on tomorrow

Get quality wires and Autolite or NGK plugs..

[Steve341]

I popped off a wire. Sure enough Male on the distributor female on the wire. To be honest with you, This is the first time I've seen this. Always seen Male on the wire Female on the cap

[Steve341]

Could it possibly be the mechanical fuel pump? Can they somewhat work, or is the fuel pump a either it works or it doesn't work kind of deal. It does not leak.