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Mounting Rochester 4 Barrel from Fuel Injection

Jessetopp

New member
So the exhaust manifold job went great today, thank you for all your help on here. I couldn't of done it with out the tips and tricks
Now, This motor, fresh rebuild. Was fuel injection, when it was rebuilt the owner wanted it to go back to carb. I have a fresh Rochester Quadjet carb. It was professionally rebuilt. I just need to mount it on the new intake.
1/place fel pro gasket down
2/place carb on. Tighten nuts down (torque specs)?
3/hook up fuel like 3/8s.

DID I MISS ANYTHING?

Here is where it gets a bit more complicated. The past owner put on electric fuel pump for the fuel injection. I would like to convert it back to manual and insert the rod I think. Is there any opinion on which is better?

Also, priming the engine. It was primed last fall and nothing since. I was going to reprime it with the priming tool before start up.

Any input of any sort or something I've missed please let me know. I am ok with motors and really enjoy working on them, this is just a project that is a bit bigger than wires and plugs on a 350 lol.
Here is a pic of what we are working with
 
The camshaft for EFI doesn't have mechanical fuel pump lobe on it. Sorry dude. If it's an engine that was originally carb and they put efi on it afterwards, then MAYBe the cam has the lobe. If there's a cover plate on the spot where the fuel pump would mount then you can stick a finger in there and feel for a cam lobe. That's all I can tell u.
 
Might consider keeping an electric fuel pump. Must use a pump for a carb which puts out about 7 psi. Also need to be sure to wire/plumb in the oil pressure switch which enables precharging the fuel line for a quick start, also simplifies filling a new/empty water separator. The pump operates while the starter is engaged if properly wired. Would not recommend "hot wiring" the fuel pump since that would be a safety issue (the pump must stop when the oil pressure goes to zero to avoid spraying the engine bay with gas after a fuel line breakage).
 
I have 1977 Crusader CH270 (350 ci) engines, and they are mounted on an angle so that they are in-line with their prop shafts (I'm just trying to say that they are straight inboard, no v-drive). I believe because of the angle, Crusader included a wedge between the intake manifolds and the Quadrajets on mine. On the attached parts diagram, it's numbered "45". The Crusader part number is 97122 (Google "Crusader 97122" and you'll find sources).

As you can see it takes two gaskets. I converted mine to use studs instead of bolts to hold down the carbs.

Do you have a flame arrester (diagram part "4") that fits a Quadrajet? If not, it's Crusader part number is 97595.

Crusader SBC Intake.JPG
 
DJR is correct about the wedge....typically a 12 degree part that will help to level the carb somewhat....

I doubt your finger is anywhere close to the size of a fuel pump push rod...you can use a hardwood dowel for a substitue push rod to see if there is a lobe on the camshaft...

Depending upon where you are, you may need a coil for the choke...there are several aftermarket suppliers that can provide an electric coil kit. if you don't need it, you will have to tie the choke plate open...

on the Q-Jet - make sure it is a marine unit....the sight tube fitting going straight into the primary bore (on the fuel inlet side) is a good indicator of having the correct carb.
 
Is this a Vortec (8 bolts holding down intake) or pre Vortec (12 bolts holding down intake). If it’s a pre Vortec you can use the divorced choke with the spring mounted on the intake right over the exhaust crossover. If it’s a Vortec there is no exhaust crossover so you’d have to figure out a way to use an electric choke if you need the choke function. As far as mechanical vs electric fuel pumps I prefer mechanical because I feel they are more reliable at least in marine use. If it’s a Vortec then you have to use electric no provision for the manual pump on the newer blocks.
 
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