/6 not wanting to start after capping off vaccum lines.

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74RR

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My 225 never would run right when I bought it so I pulled all the cracked and broken vaccum lines and capped off all the vaccum ports on the carb and some other ports. Now the car won't start at all and shoots a flame through the carb when attempting to start it. I know,I know, I shouldn't have done this. :eek:ops:
What can I look at to get it running?
 
I bet you left a large vaccum port open. I left a line from charcoal canister to base of carb off...OOPS!....hooked it up + it started right up!
 
Go to your favorite auto parts store that carrys vacuum lines and get about 5-6 feet and replace the cracked ones you took off. I hope you didn't throw the old ones out. If you hold the old ones to the length of hose it will be a template for cutting, plus it will be a sample for the shopping trip for hose.
 
Ok,thanks for the replies! I do have the old hoses so I'll pick up some new hose. All the ports are plugged,but I did notice a small gas leak that appears to be coming from the base? Could this be a cause?
 
Not likely, Refusing to start and spitting fireballs out of the carb are generally symptoms of the engine running too lean, or with too much spark advance. It's entirely possible a previous owner took and played with timing and carb to get the car to run despite the vacuum leaks. I'd richen your idle mixture a tad and try again.

Also, did you disconnect and block the line to the vacuum advance? that may be part of your problem too.

I wouldn't start playing with your ignition timing though unless you can't get it to start any other way.
 
Vaccum advance is still hooked up. Not sure if I have a power boost hose? How would I richen it up? I'm not familiar with this single barrel carb. Tha nks for all the help and advise.
 
Sorry...Does it have power brakes?
If it does there is a hose from the intake manifold to the booster that might have a crack in it?
 
If you have the 1920 holley the idle mix screw is on the valve cover side of the carb at the base. Turn the
screw counter clockwise to richen.

Check your timing and valve lash! My car was backfiring....turned out it needed a new timing chain! That's most likely your main problem. Basically the valves aren't closing at the right time and are igniting the fuel in the cylinder then thru the valve and intake/ carb hence backfire. There is a link in the Engine FAQ section for the valve lash process.
 
there is a little canister on the side of the carb called a choke pull off, it needs vacume to it or the choke will be stuck on ...........just sayin :)
 
Just thinking now,when I capped off all the ports I also put a new in line fuel filter. It's one I had laying around.
Could this be the cause if it's not for this application?
 
most likely No
74RR said:
Just thinking now,when I capped off all the ports I also put a new in line fuel filter. It's one I had laying around.
Could this be the cause if it's not for this application?
Click to expand...
 
to test to see if it is lean close the choke partially to see if the engine smoothes out or gets worse
derrangedgadgeteer said:
Not likely, Refusing to start and spitting fireballs out of the carb are generally symptoms of the engine running too lean, or with too much spark advance. It's entirely possible a previous owner took and played with timing and carb to get the car to run despite the vacuum leaks. I'd richen your idle mixture a tad and try again.

Also, did you disconnect and block the line to the vacuum advance? that may be part of your problem too.

I wouldn't start playing with your ignition timing though unless you can't get it to start any other way.
Click to expand...
 
I can't even get her to start now after monkeying around with the vaccum lines and fuel filter.
 
Sounds to me like you have a timing issue. What ever you did messed with the distributor some how. Make sure that the vacuum to the distributor is from the timed port on the carb. I bet if you get this right then loosen the distributor nut and crank the engine while moving the distributor you will get it to fire up.
 
Sounds like you've done something to get the timing out of whack and now it's way too retarded. After you get the vacuum lines back were they belong, kick the timing ahead (maybe a bunch) and try starting it again. If the vacuum advance can won't let you rotate the distributor enough, moving the wires in the cap back against the rotation does the same thing. Just make sure you are advancing the timing and not retarding it. With the distributor cap off, rotate the crank back and forth with a breaker bar. Being able to move it any appreciable distance without the rotor moving is a pretty good indication you have a bad timing chain. If the timing chain has gotten sloppy enough or the outer ring of the vibration damper has slipped on the inner (common problem on high mileage slants verified with a piston stop and a degree wheel) the timing mark won't mean much and you're going to be doing this by "feel" as a timing light only works when you know where top dead center is and the cam timing is not jumping all over from a bad chain.
 
Correction...the valve lash procedure is in the Engine FAQ on slantsix.org........I temporarily forgot what site I was on! Lol whoops! But what said before,I bet TIMING is your main problem. How many miles on the car? If it's low take in account that your odom could be rolled over.
 
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