273 with a miss

-
jimmy1

jimmy1

65 barracuda
Joined
Jun 8, 2010
Messages
53
Reaction score
0
Location
bessemer city nc
Hey Guys,I'm having a problem getting my 65 Barracuda, 273 engine to run smooth.It wants to hesitate and surge going down the road , I think its electrical but I could be wrong. I've changed the points and rotor button, coil ,and ballast resitor , the plugs on the passenger side were all tan colored and appeared fine but the ones on the other side were black with carbon , I cleaned them and put them back in but it didn't help any, also the tach works fine for about 30 seconds then it goes below 0 and doesn't work untl the engine is restarted then the same thing happens again. I've checked the wire from tach to negative side of coil and everything seems ok but its driving me nuts. Thanks in advance for the help
 
What does you're timing look like? I would replace all plugs, Cheap insurance and make sure all of your plug wires are in good contact. Next would be setting the points and making sure all of that is in spec. What is your total advance? What is the initial timing?
Is this a stock intake? Could be running rich. Black flakey or oily on the plugs?
John B.
 
Thanks Fishthatkills , nice looking cuda . I've tried the timing all over but it was running best when I set it to where the idle stopped increasing then adjusted the rpm. the points are gapped at 15 , tomorrow I'll change the cap , wires , and plugs and see what happens. What exactly does the condensor do? The plugs on drivers side of engine are a little oily on the threads but none on the conductors.When you give it gas it it cuts out bad then picks up but runs like crap , the intake is stock with Edelbrock carb. The way the tach acts is like its definatly an electrical problem. Thanks for the advice
 
Check these...

1. Check carb accel. pump for good solid shot.
2. Is vacuum advance can on the dizzy working right?
3. Vacuum leak.

Just my $0.02...
 
You might try testing the coil also. Sometimes when they are on there way out, they can cause this.
 
Compresion tester. Do each cylinder and see if there close to each other. (?)
 
did this just happen suddenly or did you change something then this started happening? it sounds more like a couple things are going on then just one. when was the last time you adjusted the valves? also did you check the float setting when you put the carb. on? see if giving the engine more pump shot lessens the hesitation and also look down the throat and see what it looks like when you give it throttle.
 
I purchased the car about a month ago and drove it home ,150 mile trip, at idle the car was hard to start and wouldn't stay running and the smell of gas was real strong , but on the highwat it ran great. carb screws wouldn't stay in adjustment ,float hanging up so I put a new Edelbrock 650 on it, problem solved but the car was still very hard to start , a couple of times it wouldn't start at all , like it wasn't getting fire ,so I checked the points and they looked worn so I changed them , set on 15 , no luck , still hard to start so I changed the coil, and ballast resistor , car cranks but runs like crap. So I put the old parts back on but the problems still there ,I think something is shorting out, I had a problem with the brake and tail light but that was a wire pulled loose from the brake light switch. as far as the timing goes, it doesn't seem to make a difference if the vaccum hose is plugged or not when I try to set the timing ,theres a marker on the engine with 5 marks on it ,one in center has 10 stamped on it with a mark on each side and the next 2 have 0 stamped on them ,when it runs best the mark on the damper is way below the last point on marker ,( is this retarding or advancing ) , so I really don't know what the number would be without guessing at it .Guy I bought the car from said he adjusted the valves just before I bought it but I doubt it because the bolts don't look like they've been off in a while but the valves are nice and quiet. Could it be a problem in the ignition switch causing the coil not to fire, the reason I say this is because the way the Tach started acting all of a sudden, THANKS for the input
 
how do you test the coil?
I think I found the problem Guys,I unhooked the vaccum advance
andthe engine started running much better,
does antone have any pointers on changing the advance Thanks for all the input it is priceless
 
:thebirdm:
jimmy1 said:
I purchased the car about a month ago and drove it home ,150 mile trip, at idle the car was hard to start and wouldn't stay running and the smell of gas was real strong , but on the highwat it ran great. carb screws wouldn't stay in adjustment ,float hanging up so I put a new Edelbrock 650 on it, problem solved but the car was still very hard to start , a couple of times it wouldn't start at all , like it wasn't getting fire ,so I checked the points and they looked worn so I changed them , set on 15 , no luck , still hard to start so I changed the coil, and ballast resistor , car cranks but runs like crap. So I put the old parts back on but the problems still there ,I think something is shorting out, I had a problem with the brake and tail light but that was a wire pulled loose from the brake light switch. as far as the timing goes, it doesn't seem to make a difference if the vaccum hose is plugged or not when I try to set the timing ,theres a marker on the engine with 5 marks on it ,one in center has 10 stamped on it with a mark on each side and the next 2 have 0 stamped on them ,when it runs best the mark on the damper is way below the last point on marker ,( is this retarding or advancing ) , so I really don't know what the number would be without guessing at it .Guy I bought the car from said he adjusted the valves just before I bought it but I doubt it because the bolts don't look like they've been off in a while but the valves are nice and quiet. Could it be a problem in the ignition switch causing the coil not to fire, the reason I say this is because the way the Tach started acting all of a sudden, THANKS for the input
Click to expand...
 
set opints at 17 th hook up vacumm gage should read 15 inches and be steady if needle bounces adjust valves. set timing useing vac gage set idle at 1000rpm ,adjust to highest vac reading ,back vac off 1 in and tighten down dist . this is done with vac advance hose off and hose plugged. you engine will be at perfect timing. i ran 1964 valaint in 1964-1966 v100 O stock 2bl 3speed and turned 14:10s
 
Great advice Bonehead , I'm satisfied that the engine is tuned to perfection using your specs , but as soon as I plug the vacuum advance hose back to the carb. it starts to stumble badly . Are these adjustable or should it be replaced ? THANKS
 
jimmy1 said:
Great advice Bonehead , I'm satisfied that the engine is tuned to perfection using your specs , but as soon as I plug the vacuum advance hose back to the carb. it starts to stumble badly . Are these adjustable or should it be replaced ? THANKS
Click to expand...
replace it
 
jimmy1 said:
Great advice Bonehead , I'm satisfied that the engine is tuned to perfection using your specs , but as soon as I plug the vacuum advance hose back to the carb. it starts to stumble badly . Are these adjustable or should it be replaced ? THANKS
Click to expand...

Are you plugging the hose into ported vacuum port or full-time vacuum port?
 
I hooked it up to the one on the left side, the port is a little higher on the carb than the one on right.
 
jimmy1 said:
I hooked it up to the one on the left side, the port is a little higher on the carb than the one on right.
Click to expand...

Check both with a vacuum gauge. Use the one with NO vacuum at idle.

If both ports have vac. at idle, you have the primary throttle plates open too far at idle. This causes all sorts of problems.
 
I don't think the one on the left has vacuum at idle , but how do you adjust the primary throttle plates ?
 
Yea i'd replace the vacume advance bout a 22 dollar part Better yet now would be the time to swap over to elct. ing.
 
jimmy1 said:
how do you adjust the primary throttle plates ?
Click to expand...

With the idle speed screw,right next to the accel.pump lever. The primary throttle plates are the ones you drive on all the time. From completely closed, they should be no more than 1-2 turns in, otherwise you expose the ported vacuum port to manifold vacuum, and when you hook up your vac advance hose, it will advance the timing too much at idle.

I don't think the one on the left has vacuum at idle , but
Click to expand...

Then thats the one to use. Confirm with a vacuum gauge to make sure.

Sounds to me like his vacuum advance can is working fine if, when he plugs it in, the timing is advancing too much!


AND, electronic ignition is NOT the answer to all ignition problems! Points work just fine when everything's working correctly, and are much easier to diagnose. Why spend over $100 when just replacing faulty parts will work for much cheaper.
 
OK Guys I verified there's no vacuum ,on the left port of carb.at idle, with vacuum guage , but it still stalls badly at the crack of throttle . When I changed the points I must have messed something up with the vacuum advance. Do I need to remove the distributor to change the vacuum advance?
 
It will be a whole lot less headache to replace the vac advance pot if you remove the dizzy from the car. TRUST me on this one. It will also give you a chance to clean and inspect the dizzy and re calibrate the points if needed. It beats bending over the fender and if you drop a screw on the bench it's a whole lot easier to find!


John B.
 
I forgot, I had the exact same problem that you have with the advance pot. Changing it out solved all of my issues with timing. That and a used electronic dizzy setup that I got for a song from a FABO member. Best thing I ever did. Runs like someone put a new engine in my car. But points work too and they are simple and easy to fix on the road. Just keep an emory board in the glove box.

John B.
 
What does the Tach do when you disconnect the advance pot and plug the port on the carb? Does the tach act correctly? Could be the tach itself or the wiring for the tach. I use the old fashioned Sun Super Tach II. Never a problem.

John B.
 
You must log in or register to reply here.
-

Back
Top