A couple months ago my engine started hesitating. I suspected a vacuum leak at the carburetor as it is a reman. Sure enough, there was leakage on my BBD around the middle gasket, I tightened the six screws and the trouble went away for a few weeks.

Of course, it came back. So I sent the carburetor to Savas Tuning, recommended on this site, to have it properly rebuilt, rebushed, etc. However, when I put the carb back on, same problem.

Here are the specifics. The car starts up fine. I have to give it a little gas, but the choke functions well, it starts closed, then the vacuum pod opens it up as the car warms.

There are just a few stumbles when I first put the car in gear and pull out. They get way worse as the engine warms. This is within 60 seconds of start up. I have major shake/stumble on acceleration. The tachometer jumps like crazy. Usually, but not always, I have to give it a little gas at red lights to keep it from stalling. Going up hills is predicatbly a nightmare. However, if I am cruising downhill, without touching the pedal, everything is smooth sailing.

I pulled the fuel line, bumped the starter and pumped the gas into a clear container. There were 5-6 real tiny specks of rust in about 1/4 cup of fuel.

I sprayed carb cleaner along the length of the manifold/engine gasket with no change in the idle.

The idle is great in park, whether I just let it run or if I pull the throttle. However, if I put it in drive, hold the brake and hit the gas there is major stumble as I start giving it fuel, it evens out and then when I take my foot off the gas it stumbles hard and then dies.

The tailpipe is spitting water with a few slate gray flecks in it.
Thanks for the input.

_________________
God took you away, then brought you back to me.

Does it miss at all from 2000 to 3000 rpm in park? or is it nice and smooth?

How much water cam out with the rust? Do you see any small beads in the bottom of your bucket?

You could have pumped a bunch more water in the carb to where it sputters under load.

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

There was no water in the fuel, but I only pumped out about 1/4 cup.

When I tested the car originally it was smooth between 200-300 rpm. However, when I went back out to check your questions, the engine had cooled for about 30 minutes, and I couldn't get a smooth idle in park. It vibrated, real rough, regular bump in the engine, especially if I gave it any gas???

So are you saying I should pour water down the mouth of the carb? What does that tell me? I'm not familiar with that test.

_________________
God took you away, then brought you back to me.

Your fuel pump may be faulty, or more likely it's not putting out enough pressure, especially if rust specs have gone through it.

how do i test the fuel pump?

_________________
God took you away, then brought you back to me.

To test the pump you would have to install a pressure gauge.

No, don't poor water in the carb.

Since your car was running fine, I am taking a calculated guess. I had this problem three weeks ago. I let the tank get too low before I gassed up and bingo.......sputtering problems. I put in some Heat, (alcohol based gas dryer). It comes in a yellow plastic bottle, don't use the STP brand. Then I cleaned out the float bowl and sprayed it with carb cleaner. It had lots of water balls in it.

I am wondering if you have water in the bottom of your float bowl that might be affecting a smooth flow of gas into the jets

If so, sometimes water balls or droplets will roll around and temporarily plug the jet.

This is the time of year where you can get allot of condensation in the gas tank. So some "gas dryer" should help. Dump out your fuel filter too....

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Shouldn't be water in the carb as I just got it rebuilt and I had this problem with it straight out of the UPS box.

Is it worth the time and money to buy a fuel pump pressure guage and install it, or should I just get another fuel pump and see if that improves things. As I recall its only about 30 bucks and I'd like to get this fixed ASAP.

_________________
God took you away, then brought you back to me.

If the pump is old, like mine was, why not? It wouldn't hurt.

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

There are only two reasons I hesitate. First, the pump is less than 2 years old. But if that little bit of rust has affected the diaphragm that doesn't matter.

Second, and more important, is that when this problem originally occured I was able to get rid of it for a week or so by tightening down my carburetor screws. It could be that there were multiple issues going on at the same time, vacuum leak on the carb, faulty fuel pump, I just want to make the right diagnosis.

_________________
God took you away, then brought you back to me.

Too bad you don't have another carb to swap with.

If you had it professionally rebuilt you would think it would have been bench tested. I would call the rebuilder.

I had a carb that did that, it had a hairline crack, I ended up setting it aside.
No more problems with the new carb.

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

u say its a BBD and u had it rebuilt. did they rebush the butterfly shaft?

D~~~!

Your fuel pump is not at fault here. Definitely sounds like a carburetion problem, and if you could see flecks of rust in your test fuel, you probably have some clogging the carb. Have you tried blast-cleaning the air bleed tubes with spray carb cleaner?

You will also want to check to make sure you haven't got an exhaust leak into the intake manifold by way of a faulty or stuck EGR valve or a crack in the manifold floor.

And if tightening the screws affected the problem, remember there are additional screws only accessible from the bottom of the carburetor (requires carb removal).

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.

I am told the BBD was rebushed.

If the problem were caused by rust, it would not have disappeared when I tightened the carb down a couple months ago, would it? And would an assumedly perfectly rebuilt carburetor be affected instantly, right out of the box by the rust, or would it take time to build up?

How do I check the EGR valve? I read somewhere that its a hockey puck shape located between the valve cover and the manifold but I have nothing matching that description in that location.

I do have carbon deposits on the engine block around rails 3 and 4 of the exhaust manifold along the gasket. That looks like an exhaust leak, right? When you say manifold floor do you mean the area where the carb sits?

I have a fuel tank kit coming from Eastwood, with a cleaning, etching and sealing solution. If the problem is rust, resealing the tank and cleaning out the carb should take care of it, correct?

_________________
God took you away, then brought you back to me.

if ur problem is rust and u clean and seal the tank, u will still need to purge the rest of the system, including ur fuel pump and especially that newly rebuilt carb.
D~~~!

I can pull the fuel line coming off the pump and crank the engine to clear out the lines from the tank through the pump, but how do I properly clear out the carburetor?

_________________
God took you away, then brought you back to me.