Rebuilt dual 40idf car won’t start

[SpyderJoe]

Hi group,
79 Spider running dual 40’s. Ran great for 5 yrs. And started running poorly after some recent work done on transmission, (not related). I pulled them off to inspect and rebuild them. Lots of red varnish in the float bowl. Tore down the carbs, cleaned them up and bought 2 rebuild kits. Reassembled them slapped them back on. At first it started and ran poorly. I couldn’t tune them to improve. It got to the point that now the car won’t start. It turns over strong but doesnt fire up. I took them off and the gasket between the manifold and the rear carb was soaked with gas. Couple questions:
1. Why would the gasket be dripping with gas? Maybe tit wasn’t tight to the manifold? It was tough to get nut screwed down but I thought I was able to.
2. I didn’t remove and inspect the starter valves on the carbs. What is their function? Could this be the issue if there was junk in them?
Any advice?

Thanks guys.

[18Fiatsandcounting]

I don't have any experience with IDFs, but any chance your engine is simply flooded? I do agree that the manifold/carb gasket shouldn't be soaked with gas, but you could try cranking the engine with wide open throttle (no pumping) and see if the engine starts to fire after a while. Or, remove your spark plugs and wait a few days and then try to start.

-Bryan

[Nut124]

I'd suspect a float/needle valve stuck open or not closing properly.

If you have an electric fuel pump, turn it on and watch the carbs - no fuel should be dripping down the throat.

[dshaw66]

Just had a flooding issue with my 44s after a rebuild. When putting on the top, the float got hung up and wouldn't close the valve so gas flooded down the aux venturi. Took the top off and re-seated it, all good.

[SpyderJoe]

So I figured out the non-starting issue. Carburetors were still very dirty. I was able to spend some time this weekend to pull them off and clean them up. Got the car started but it’s still running a little poorly. Seems like it’s “putting“ During acceleration and under load. It also putts at idle. It’s almost like it is down a cylinder. I will run a compression test later today when I get home from work. I am also going through all of my jetting to make sure everything is the right size. I am not any type of expert with electrical issues, however Can the timing be off? I never touched it.
I also never changed any of the jetting. It has run great for years so I don’t think I need to change anything here.

Thanks for all your support.

[seabeelt]

Did you ever solve your issue.

I’m guessing something wasn’t put back the same way it cam off

Manifold gaskets need to be tight otherwise your sucking too much air at that joint and not enough fuel because you don’t have proper flow past the Venturi openings

Gasket however should not be wet unless you were trying for an extended period of time and pumping the pedal

[18Fiatsandcounting]

Reminds me, I gotta look up Pete. I bought some parts off him a while back, and I gotta bug him some more to see what he's up to. He might not be in the Bay Area anymore, though...

-Bryan

[HappyHog]

Could it be as simple as a fouled plug?

I had this when I was fighting a rich at idle condition that I eventually was able to sort out. During all the sorting out, at times the plugs seemed to foul making it seem like it wasn't hitting on all cylinders. When it did that, I pulled them and simply cleaned the soot off the plugs and it hit on all cylinders again. Just a thought.

Happy