Lack of Power and Running RICH: L20b in a 1980 720 2wd

[Bill_P]

I have a 1980 L20b 720 2wd Standard Cab

I cleaned the motor with Gunk brand engine cleaner two days ago.

I removed the AC system (I still have to remove the pump and reposition the smog pump, but the condensor and all underhood hoses and fittings are gone).

I replaced most vacuum hoses two days ago.

I removed the mechanical fan, and shroud, and replaced it with an electrical cooling fan.

Otherwise the motor is stock...

 

The problem is that I cleaned the motor, and now I am getting too much fuel, backfiring in 3rd gear, black soot in my carb and fouling my plugs, and a general lack of power with sputtering (unless I floor it, then it accelerates like a 280z!).

It has a good coil wire, and plug wires.

The rotor and cap are fairly new and not worn or burnt.

The fuel filter is new and clean.

The vacuum system is routed correctly with no known leaks.

The coil, ignition module, and battery seem to be firing just fine.

 

So why all of the sudden the lack of power and crappy gas mileage?

Maybe I got some of that cleaner crap in my fuel system???

I have driven it 50 miles since with no improvement.

Ugh, please help!

[banzai510(hainz)]

you make sureno condensation under the dizzy cap?

[Bill_P]

No condensation. Although, the Gunk cleaner could have made it's way into the carburetor or fuel system somehow. I am going to fill it up with gas, and add a fuel treatment that eliminates water and cleans out deposits.

[racerx]

thats what I'm thinking about the gunk, you did not cover your carb with plastic or something.  I covered mine with a siplock bag.  Good luck and let us know what the heck happened,

[datzenmike]

Take the top off the air filter when warmed up. Does the choke look like this...

 

 

... or like this????

 

 

 

 

 

 

.

[Bill_P]

Its open when its hot. What the hell is the deal with posting pics? Do I have to go through a 3rd party host, or can I just upload them directly??

[datzenmike]

3rd party hosting.

[datzenmike]

Check the air filter. Is it wet, dirty?

[Bill_P]

No its all clean and dry.

 

I figure there is an air leak somewhere around the carb baseplate or riser gaskets that the Gunk got into. Im getting good spark, and the cap is dry as a bone. This same thing happened when I rebuilt the carb. It ran like shit until it burnt off all of the microscopic deposits of the cleaner I used. It was better today than it was yesterday.. I was just hoping someone knew a quick way to eliminate the flooding issue.

 

I checked the vacuum system again too. Its dialed. Fuel filter, and pump are dialed. I unwrapped and checked the wiring, my plug and distributor wires, and plugs, and they are all good. Plus the truck is relatively low mileage. I bought it 18 months ago with 49,000 original, and its at 105,000 now. I have driven the shit out of it, and kept it well maintained.

 

Im going to pull the carb in the morning, and reseat the gaskets. Maybe it just has a fatty air leak or something..

[Bill_P]

I completely cleaned the carb gaskets, and retorqued the four 12mm nuts that hold it to the intake manifold... runs like a champ now. Thanks for the help!

[Bill_P]

I also replaced most of the m4, m5, and m6 stock metric hardware with stainless steel socket head (alan wrench) bolts. I come from a bicycle mechanic background, and alan wrenches are SO much easier to use than screwdrivers!