Switched from a open carb spacer to 4 hole

[rsd859]

Ever since I made this switch, the engine has a hard time starting up after sitting for a couple of days. With the open spacer it fires right up.

What would cause this? Once its running I dont have any starting problems.

Thanks, Rich

 

[67 coronet]

have you switched back to the open spacer to check if that is the actual problem?could be something else is wrong and just croped up when you changed the spacer.spacer design shouldt have a big impact on cold starting and ,if anything,would be a bit harder with the open one(less velocity of flow)

 

[WP29440SE]

you could have jiggled the floats and stuck a needle valve while moving the carb around in the process. tap on the float bowls.

 

[rsd859]

I will try it, thanks guys!

 

[Dako]

Funny you bring this up. I've never had anything but the spacer with the individual holes and have always had to 'pump it' if it sets for more than a week. Thought it was just gas evaporating. Maybe I have a problem and don't realize it? Will be following this to see what the responses are.

Engine specs:
`66 Poly 318, .040 over
2.02/ 1.60 valves, ported heads
262/.460" ([email protected]") re-ground cam
`62 cast iron 4 bbl intake
650 Edelbrock AVS Thunder series w/ elect. choke
1 " (4 hole) phenolic carb spacer
Skip White electronic Dist.
TTi headers, 2 1/2" dual exhaust

 

[rsd859]

I don't know when I will have a chance to swap it back out, but when I do I will post the results here. I was also thinking it may be due to a lack of fuel pressure.

 

[HT413]

If you question fuel pressure on startup, try priming the carb. If it starts but then dies after maybe 10-20 seconds, the fuel pump isnt supplying any fuel and the bowls are emptying. Bt if you can get it running for any lengthof time, my guess is the pump and fuel system are doing their job.

 

[snakeoil24]

The gasket is not cut right and blocking the idle circuit?

 

[383man]

What intake are you running with the 4 hole spacer ? Ron

 

[rsd859]

Stock cast intake. Which gasket Snakeoil?

 

[Meep-Meep]

I was going to ask about the intake.. Running a divided plenum dual plane with an open spacer will expose all 4 throttle bores to all eight cylinders all at once but a 4 hole spacer will isolate half the carb and will affect the signal to the carb. Seems counter intuitive that isolating side to side will make things harder to start since the signal is typically stronger because of the isolation, so there must be an explanation somewhere. Also at cranking speed there isn't a lot of velocity so I wonder if spacers have anything to do with it at all. Are both sides of the carb tuned equal? Mixture screws about the same amount of turns out from lightly seated? Just wondering about the possibility of one side being very lean but since the open spacer the other side was providing enough fuel to the side with the more easily accessible path to the intake valve thus making the engine fire easier. Just throwing out ideas!

 

[rsd859]

Very interesting meep,I do have both mixture screws adjusted the same.

 

[Dako]

Mine are also adjusted approximately the same...

 

[68 Sport Satellite]

interesting! Let us know what you find out.

Not that it matters, but can you tell us how thick your spacer is?

 

[rsd859]

Its a 1" Mr. Gasket with the interchangeable phenolic inserts.

 

[Cranky]

Have you checked your manifold vacuum and fuel pump psi? That's usually the first things you should check with any combo....

 

[rsd859]

I'm pullin 10" of vac. Not sure on the fuel pressure but once it's running I know it's sufficient. Just starts really hard after sitting for a few days. Could it be the cheap gas I put in?

 

[snakeoil24]

Stock cast intake. Which gasket Snakeoil?

the gasket between spacer and carb base. Also if your running a duel plane cutting a notch in the dule plane will help equalize distribution of fuel.

 

[rsd859]

I've got the 4 hole gasket in place under the carb.

 

[68 Sport Satellite]

Its a 1" Mr. Gasket with the interchangeable phenolic inserts.

I'm running the same 1" phenolic Mr. Gasket spacer with interchangeable inserts. When I installed mine I had some underlying electrical issues. Was hard to start cold after I installed the spacer (which I originally did to combat heat soak hot starting issues with fuel boiling). Then I replaced the chrome ECU, the voltage regulator and ballast, and the coil. After all that it would fire right up on the first crank. It was sweet! However, it was smelling pretty rich on fire up. I'm new to tuning or adjusting carbs and a buddy that helped me with some suspension said he thought it was running rich. He leaned it out and said he had it running better, which may be, but now after sitting for a few days it takes 4 pedal pumps and 2 cranks of the key and then it fires.