First time touching a carb. Going to attempt a repair on the Holley 2bbl.

[MattP]

First let me first say I know zero about carbs. I've never worked on them, never tuned them, never even had a vehicle that had one. So if some of my comments or questions seem a little low on the "common knowledge" meter please cut me a little slack.

My Duster came equipped with a Holley 2bbl. Symptoms lead me to believe it needs a new accelerator pump.

-Will not start after sitting for extended periods, "overnight", but will fire right up if I just turn it off for an hour or two.

-There is a huge flat spot when I give it gas from idle. If I'm not very careful it will die. I have to barely touch the throttle to get it passed this spot then it will run just fine. "Not the best situation when that dump truck is headed for you!"

This 2bbl is a short term piece on this car so I'm not really worried about messing it up. My plan is to head down to O'reillys and see if they sell the accelerator pump for this carb. I've seen rebuild kits, but I think the A pump and the rebuild kits don't overlap.

Here is a pic of the carb.

and the only identifying number I found

I'll let you guys know how it goes.

 

[MattP]

Well the local auto parts stores didn't have what I needed so I guess I'll be ordering a rebuild kit on the www. I'll update when there is something else to talk about.

 

[67Dart273]

I see no photos? But cleaning it and a new kit is probably a good start.

 

[MattP]

I see no photos? But cleaning it and a new kit is probably a good start.

My Photobucket was acting weird earlier so I used some other image hosting site. I swapped the original post back to Photobucket. Maybe that will fix the pics for you.

Turns out the carb is a Holley 2280. After watching the instructional videos Mikes Carburetors put on YouTube I ordered a rebuild kit from him. He wasn't the cheapest, but without the vids I would have been lost.

The car runs great other than the accelerator pump issue. Unless it just looks gunked up when I take it off I'm prob going to just swap out the accelerator pump and see how it goes.

 

[MattP]

Would you guess that after I had to use a little Marvel Mystery Oil to prime the carb after getting caught with no gas in the bottle it stopped having any issues?

I guess the accelerator pump was gummed up and the MMO cleaned it up. Carb is working 100% now and I have a rebuild kit just in case. lol

 

[BillGrissom]

To test the accel pump, open the choke and look down the bore while pulling the throttle cable open fast. You should see squirts of gas. Of course, do this with the engine cold or you could burn your face.

The "hard to start cold" problem probably isn't the accelerator pump, but rather the choke and associated linkage. If the engine was cold in the 1st photo, the choke isn't set correct and will be too lean when cold. The plate should be shut firmly by the rod coming up from the exhaust (adjustment on the thermal spring in exhaust pocket).

Once the engine fires and generates manifold vacuum, the "choke pull-off" should pop the choke open slightly (~0.25", don't quote me check the manual), otherwise it will idle too rich and probably die. The pull-off is the small vacumm can in the upper left of your 1st photo. It is common for the rubber diaphram to fail. Test it with a vacuum pump or pull the vacuum tube, push in the rod, and cover the hole with your finger and see if the rod stays in. You can buy just the pull-off.

 

[KitCarlson]

I have rebuilt a couple with good results. They are a good running carb, with excellent fuel economy. Been getting low 20's mostly with in-town driving, A/C on, with 273 V8.

I may be interested in buying yours if you decide to change it out.

 

[MattP]

I have rebuilt a couple with good results. They are a good running carb, with excellent fuel economy. Been getting low 20's mostly with in-town driving, A/C on, with 273 V8.

I may be interested in buying yours if you decide to change it out.

I will be changing this carb out for a Holley 650 DP in the not so distant future. I would be nice to have this one sold when it comes off.