Can't get BBS to Idle properly

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1970Dart198

1970Dart198

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I just rebuilt and installed an unused BBS for my 198 slant six. It has ECS, with the fuel pump hose for vapor. It also has a hot idle compensator valve which I put a new gasket on and installed. I set the float to a 1/4 inch inverted. I put it on the car and she fired right up. But the engine can only idle between 1,000 and 1,200 rpm without dying.

I plumbed off the heated air snorkel nipple.

What should I do next?
 
Another thing, with the pcv hooked up. The slant fires up then dies. Without the pcv hooked up it'll idle fine at 850 rpm all day. Vacuum leak? I also have the bowl vent hooked up to the fuel pump. Could this be the issue? How do I fix this so I can keep the hose?

I would also like to add that I'm trying to make my 70' Dart factory original with the ECS system. I dont have a pressure- vacuum filler cap for the gas tank, I have a normal one, could this be causing the issue when everything's hooked up?

Thank you!
 
When you say PCV not hooked up, do you mean the hose is disconnected and plugged? If so does pulling the PCV and covering the hole with your finger do the same? Sure does sound like a leak elsewhere.
 
The car can idle with the PCV installed and the ECS hose for the Bowl Vent plugged. If I have both hoses plugged into the car at the same time it wont idle for anything.

I also have a noticeable bog in acceleration when I go from a stop. It bogs down almost till it squeaks out dead, and then it surges.

I'm running the 5 month old gas out of it now. I treated it with Sta-Bil gas treatment, maybe there's water in the gas?

Thanks
 
1970Dart198 said:
I just rebuilt and installed an unused BBS for my 198 slant six. It has ECS, with the fuel pump hose for vapor. It also has a hot idle compensator valve which I put a new gasket on and installed. I set the float to a 1/4 inch inverted. I put it on the car and she fired right up. But the engine can only idle between 1,000 and 1,200 rpm without dying.

I plumbed off the heated air snorkel nipple.

What should I do next?
Click to expand...
i had the same problem if you have points check the condenser a had a bad one and the car would only stay on giving it a lot of rpms i thought it was the carb so i rebuilt it still same deal then ended up being the damn condenser
 
Well if it idles with one of the 2 hoses plugged, then the condenser would seem to be OK.

As for the PCV and ECS, I don't know this area too well, but the ECS bowl vent is pulling vapors through the fuel pump connection, the crankcase, and then the PCV. If The ECS bowl vent is bogging the car's idle, then it almost sounds like the bowl is somehow being vented in another spot and is drawing too much air in via the bowl. Is the top cover all secure and any top gasket good? Was this a brand new, out of the box BBS, or could it be a rebuild where a 1970 ECS top is mixed with a different body and you have an added vent into the bowl via the body?

You may find added info here from someone whose name you might recognize:
http://www.allpar.com/fix/fuel/evaporation-control.html
 
Ok, I fixed the cold start issues, I have a new issue with acceleration bog.

This appeared after I rebuilt and installed a new, not re-manufactured carter BBS.

The car will fire up just fine at a nice fast idle, I let it warm up for a minute or two and I push on the pedal to put the carb to a nice mid-idle, I back out of my driveway, put it in drive, and put my foot on the gas.

I'm only gently accelerating, and the car stumbles, and almost stalls, sometimes it does stall. This happens until my engine fully warms up and then it goes away.

I'm going to replace my spark plugs since they are two years old. I had the NGK ZFR5N with the washers removed.

I also installed a new fuel pump with the ECS vacuum fitting for my 1970 198 slant. I do not have that hose hooked up, its plumbed.

The old fuel pump oddly enough had more travel in the fuel pump arm, this new one is a little tighter with less travel.

I have the float set dead on, and the choke operates well, wide open when hot, closed when cold.

My fuel tank gas cap is also the non-venting type, I have ECS on my 1970 Slant six, could this cause issues?

What do you think?

Thanks.
 
The float bowl has to see atmospheric pressure period.Period.
The accelerator pump has to spurt fuel at the slightest , tiniest. ever so gentle ,throttle application.
The choke may need to stay on a little longer.
 
Well that explains the stalling out, thanks!

I think I've narrowed down the bad idle and acceleration bog.

I hear a whistle when I'm driving, The whistle goes away when I accelerate, after the bog, but before that with my foot off the pedal if Im just going I hear a whistle which indicates a vacuum leak.

I pulled off the distributor vacuum advance hose from the carburetor and sucked on it, then putting my tongue over it. It did not hold vacuum at all. I looked down at the diaphragm pod in this kind of "peep" hole where you can see the diaphragm moving. I sucked on it and it didn't move at all, it was like sucking normal air.

I ordered a new diaphragm pod, I have the Pertronix system in the distributor, works great. I know I'll have to remove the system, but can I replace the pod without removing the whole distributor?

Thanks.
 
1970Dart198 said:
... can I replace the pod without removing the whole distributor?
Click to expand...
Sounds almost impossible on a slant. But, it isn't hard to remove the distributor. First, mark where the rotor is pointing w a Sharpie and put it back the same. Note that the rotor spins as you lower it, so add windage for that until you get it on the right gear tooth.
 
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