Trying to figure out my carb problems and I just did a test that I thought made sense and am now left thinking either my test didn’t make sense or my carb is indeed messed up.
Disconnected the fuel line to the carb and attached a few foot long fuel hose. Tried blowing through the hose to see how much if any resistance there was. Couldn’t for the life of me blow any air through, with the throttle in idle position or if I manually pushed it to the pedal-to-the-floor position, same thing, like trying to blow air through a brick wall. Is that how it should be? Impossible to blow air through the carb via the fuel inlet?
If i understand carbs at all (I don’t) it’s gonna be using engine vacuum to operate under normal conditions. But when trying to start the car for example, there’s no significant vacuum while the starter is cranking, and it manages to draw fuel through enough to start. Right?
So is my test invalid? Or is my carb messed up? Maybe both?
If the float bowl is full then you wont be able to blow into it as long as the needle seals properly. If you were to drain some of the fuel then you should be able to blow into it.
Good thinking, but Mike is right.
Work the throttle and see if the accelerator pump is working properly. (should be a squirt in the primaries when you work the throttle quickly.)
Yep when I push on the throttle I can see a drip of fuel falling into the bowl.
I’m trying to troubleshoot a recently new problem where after my car sputtered and died there was fuel percolating in the carb. Sounded like breathing, and saw bubbling in the bottom of the carb.
I added the fuel pressure regulator I had bought months ago when I first read that the fuel psi of the stock ford 302 pump is more than the maximum spec of the Edelbrock 1406. Trying to address the possibility that the percolation is a result of excessive fuel pressure.
There’s a new problem today, which is that when I go to turn the key to start the car there is nothing. And when I fire it up using my remote start button under the hood it cranks.
I’m thinking that maybe the source of all the trouble is my ignition switch, and that the fuel percolation thing maybe always would have been there but I never noticed it for some reason?
Trying to pin down a couple issues at once I guess. I do think the carb might need addressing, so I might try and get someone to help me with that since I have zero experience pulling a carb off or opening it up and would rather not make more problems than I already have.
Well thanks for the clarification that my test was flawed in its concept. Glad to know that the problem was the test rather than the carb!
If you’re only getting a dribble through the accelerator pump, you probably need to pay close attention to that circuit.
The carb has 4 fuel circuits: idle, cruise, power, and accelerator pump. Get 'em all clean because a bunch of iron oxide in an aluminum body carb is a chemistry problem waiting to happen.
Is there anything wrong with rinsing it down with water after I remove it? I just used an eyedropper to remove the fuel (and rust) that was in there so most of it is gone. But I would think rinsing it off before disassembly might help get rid of more of what’s left. Then let it dry and take it apart and hit it with compressed air. Rinsing ok?
If there’s that much crud in the bowls,…the fuel filter must of plugged solid and then the element blew out. The filter is suppose to keep junk out of the carb,…fail.
All that came from the fuel bowls!? Filter must be crammed nearly full. Hopefully the heavy rust just settled to the bottom,…not clogging the carb passages. Imagine if you had not installed a filter,…you more than likely would have to dig the bowls out with a spoon!
Iron oxide is much harder than iron, so hard it is used to make abrasives. The bad news is that you have been feeding some of that stuff into the engine.
A word of advice. Change out the tank lines and filter before you start the car again. This is exactly why I tell people to change out the tank and lines before they do any thing else, not to mention the shellac that has been painting your valve stems…
Well I did take your advice a while back Bill and got my new tank and lines a couple months ago. Just haven’t installed them yet. And yes, the tank and lines will be replaced and carb cleaned before the car is started again. As well as pulling off the dash to repair or replace the ignition switch and replace the tach. Time to pull out the battery tender that I thought would be in the cabinet until winter naptime. :-/
I answered you post on this topic in the “hello all” thread. I didn’t have a clear vision of what you were seeing till I saw these pictures. That is way to much rust, forget about the filter and change the tank and lines. Bill is correct, iron oxide is what is used to make grinding wheels. So that rust like running little grinding wheels inside your engine. Not good. It’s a bummer to take your Cougar off the road to change the tank but it will be better for it in the long run.
Steven
Just take it one bite at a time.
I would put the top back on the carb, leaving it attached to the engine. That way you don’t have to figure out what goes where when you get your switch, tank, lines, and whatever else finished.
The carb will still be there, and no rats will have crawled into your engine and stuffed it full of bird seed and seat stuffing.
Already put the top back on the carb. And shot a video walk around of the carb, what is connected where, which rods were attached with pins to assemblies on the top, etc. then closed the hood.
Tank, lines, switch, and tach first. Then I’ll pull the carb, clean it all up… Maybe even take the intake manifold off since the carb is already off… And then turn into one of those stories of the guy going to change a hubcap and ending up rebuilding the engine and trans and replacing a bunch of body panels…
Don’t become a statistic! Garages and backyards across the county are full of classics that “need a little carb work”. Do you have an intake leak? Heck it’s just now springtime! I see a good summer full,… full of nice warm evening cruisin’ in your future!! Step by step,…chew each bite 10 times and all that good advice!
I don’t want to be the i told you so guy LOL! Keep in mind that I figured out the fuel tank thing by destroying not one, but two 390s. I got most of my education at MIT (Mistakes I Tried). I know more wrong ways to do things than I can count. Hang tough this is just part of the adventure… one step forward, a year in the body shop.
No “I told ya so” at all Bill! I recognized your wisdom from the day I joined this forum and I ordered the tank and lines as soon as I had the money even with other knowledgeable folks telling me not to bother. I know you are a smart feller and you know more about this stuff than most guys I ever get to talk to. I make a point of doing my best to heed whatever advice I am fortunate enough to get from you. Cheers!
