Carb troubles- need help!!!!!!

O.k., this is in regards to my 82 Mercury Capri RS.

it has a stock 89 lonmg block w/ 82 factory 2bbl intake and a self regulated Carter electric fuel pump (max 8 psi). Manual transmission (T-5)

It had a 500 cfm Holley 2300 carburetor.

Started flooding out o few days ago, then it decided to spill massive amounts of fuel onto the intake from the accellerator pump.

I decided I would order the rebuild parts, and use the Holley 350 cfm from the 73 Maverick (about 2-300 miles on it) until I got the other one straightened out.

I had a very bad day yesterday, swapped the carb, and fuel started shooting out of the the fuel bowl vent.

After adjustmenting the float, that was resolved.

I could not get the idle under 11-1200 rpm, I had the same problem w/ the 500 cfm.

The choke is all the way open, so the fast idle cam is not engaged.

The old carb has no choke assembly at all.

The linkage is not binding, and is operating fine.

All vaccuum line (2) are connected, and not leaking.

The accellerator pump is adjusted perfectly, the throttle response was crisp and immediate.

The air/ fuel adjusting screws were set at (2) turns out on both sides.

The car ran pretty good for about 2 minutes, then bogged down, stalled, and I could not get it started again.

It ran pretty well (accept for the high idle) while sitting in the driveway.

Can any of you carb guru's help me out?

This is my daily driver, I need to get it running ASAP.

Thanks, guys!
Jim P.

 

Sounds like you've got a piece of trash in the needle/seat, allowing it to stick open. Are you running an inline fuel filter bewteen the pump and carb ? As for the high idle, you may have the throttle open too far exposing the transfer slot, putting it into transition between idle and the cruise circuit. Also check the powervalve to make sure the diaphram isn't ruptured. Uncrew it and suck on the diaphram side to see if it's functioning. The accellerator diaphram and powervalve diaphram are the two things that can rupture if the carb sits too long. Trash in the needle/seat can be a problem if it's not fed clean fuel. If all this fails look at using a fuel pressure regulator between the pump and carb.

 

I have an inline fuel filter between the carb and pump.

I took out the needle and seat yesterday and it was clean.

I am getting a fuel pressure gauge today, and I'll check that, too.

Another guy mentioned the cork seals on the air/fuel mixture screws, is this a common problem?

I have the 500 completely disassembled, so I want to try everything I can externally before ripping into the 350.

The rebuild kit for the 500 cfm carb and a fuel pressure regulator are on their way from Summit

Thanks for the help!

 

I installed a fuel pressure gauge today, and i'm getting a steady 5 psi.

The car started to smoke a bit, and it smelled like it was running really rich.

I shut it down, and removed a plug, it was completely black.

??????

 

if the car has flooded out smell the oil and make sure its not full of gas then check your base plate gaskets sounds like a vacume leak i have had a egr valve go bad and leak vacume

 

Something still stuck in needle & seat or bad power valve. What happens if you start to close the choke? The cork seals on the idle mixture screws you're referring to must be in place. Also check the throttle shaft where it comes through the base plate for excessive play that could be a vacuum leak. Make sure the check valve under the accelerator pump squirter is not missing. Possibly a vacuum hose somewhere away from the carb is leaking or disconnected? I know you said the plugs look black/rich but have you checked your timing? Just throwing some things out there for you to check.

 

If the 350 CFM idled & ran OK on the Mav, you have other issues, sounds like a vacuum leak... I'd disconnect and plug the vac connections to the intake, PCV would be a major suspect(I've seen the guts fall out of the plastic Motorcraft)... Also I'd be sure the EGR is closed...

Not restarting kinda points to a plugged exhaust system, but conflicts with the fast idle issue... Does this thing have cats??? Checking vacuum would be a good idea next time you get it started...

 

No cats, no EGR.

The only vaccum hoses from the carb are the PVC and distributor. Power brake booster is running from the intake.

I will check all vaccum lines tomorrow.

Rebuild kit came in today!

I cleaned the plastic spacer and intake real well, but I'll check for leaks there too.

Thanks for all the replies!

 

Throttle shaft was a little scored, and there was corosion on the shaft. There was corrosion on the shaft where the plates mount also, and rust on the steel plates. I bought a replacement throttle base plate assembly. Should be in Tuesday. The rest of the rebuild is done. The check valve under the acc. pump was just a small red rubber "plug" type. I replaced it with the same type which came w/ the kit. Cork seals for idle mixture screws were hard and britttle, new ones installed. Power valve, needle and seat, acc. pump diaphram, etc, all replaced. Just waiting to screw the new base on now.

 

Blow out all the passages with spray carb cleaner, followed by compressed air (wear eye protection while doing this) One small plugged passage can ruin a rebuild experience. Also check that the check valve is present under the accellerator pump nozzle, this is a square plug with a pointed lower end that drops into the passage under the pump nozzle, without it in place, the vacuum will draw fuel into the engine from the pump circuit.

 

The carb was surpisingly clean inside, but I went all out with the carb cleaner. All passages are spotless.

I had watched about 30 videos on youtube regarding the rebuild, so when I disassembled the carb, I used small ziplock bags for the parts from each area, acc. pump, bowl, metering block, etc.

This made the reassembly very easy, actually, this is a very simple design. I had only rebuilt a one bbl carb previously, maybe 20 years ago on a Nova. Needless to say I was a little intimidated, but it was easier than I expected!