Ok, my 268 just didn't start one day. Turns over. I went and changed the coil, points & condenser thinking that. Still no start. Checked fuel flow from pump and it was dry. Rebuilt the pump and now it's getting gas. Still no start. Checked for spark and didn't get any. Just for fun I put back the old points and condenser. Now I have spark. Still no start. Now here's what I find strange. It turns over with the usually sound. When I pump the throttle and get a little gas in her, it turns over with a different beat. Kinda like a cold northern winter when you don't plug in over night. It then goes back to the usually turning over sound. It's almost like when the amount of fuel I've pumped into the carb gets used? I even poured about a 1/4 cup of fuel down it's throat with same effect. I'm absolutely stumped! I also rebuilt the carb a couple months ago and it ran great before this. I will add this....when I rebuilt the fuel pump, I noticed a little piece of broken rubber from one of the check valves. Could a failing pump put some crud back into my niece clean carb? I really don't want to tear it back out without a little more convincing haha, thanks and I really need some advice cuz I ain't got nobody else to ask.
I had a fuel pump push rod seize on an 8ba once. You might want to crank the motor with the fuel pump removed to make sure the rod is going up and down.
Before you even get this thing running again definitely do this. Drain your oil. It'll have a ton of fuel in it and will burn your valves. Basics. Fuel? Maybe not. Air? Maybe. Maybe not. Spark? Yes you indicated you now have spark. Compression? Ran well before. Sounds like you need to concentrate on your fuel and air. Be absolutely sure your getting good fuel pressure at 4 lbs. time to buy a pressure gauge set. if so..... Next pull your carb and clean it. Take it apart and clean all orifices. Good practice. You could also have blown a power valve in the course of trying to fire it up.
Fuel pump is dual diaphragm run by a cam. I will drain the oil as you suggested to prevent any further damage. You would think a new pump rebuild would supply the required 4lb pressure. I'll pull the carb and double check all passages. Thanks for the suggestions and welcome any others!
I assume you car is a 6v system? If it is, try a 12v battery to see if it helps, just for trouble shooting reasons. I ran a '32 pickup with flathead on a 12v battery and never had any problems with the starter. All the bulbs were 12v, be carefull there.
Since you can pour gas into the carb and it will not fire and you have spark, I'm thinking that the cam sprocket has deteriorated to the point that it's not allowing the cam to turn or only catching on a few teeth.
It's a 6 volt system. New battery was a little low so it's being trickled as we speak. Cam sprocket? Yeesh...hope not.
How old is the battery? Have you done a load test on it? Buy an Optima; if you plan on driving this car at some time in the future, it's the best investment you can make. (Oh, make sure you buy it from someone that will honor the warranty; they are out there.)
Seriously try this now... I think you have a big vacuum leak. Make sure the intake is bolted down with the correct torque and gasket is good as well as the gasket at base of carburetor and tighten. Shoot a spray of Berriman B12 into carb and let me know what happens.
I think most of your answers have been referring to Flathead FORD V8. I read it that way, and was about to ask if you had checked the fuel pump pushrod length..... until I looked at your avatar then profile and older posts, .......your 268Pontiac Straight 8 is a different beast... http://www.secondchancegarage.com/c...ntiac-268-127hp-inline-eight-engine-specs.cfm As you started with a pump which was not pumping at all I think you need to check the flow rate of the pump at cranking speed~! How much fuel it will move in 1 minute, into a quart measure (get one from the kitchen ) . Look for 8-12 ounces per minute at cranking speed. next check or dirt /debris in the needle and seat in the carb, a small piece of junk there will have the carb flooding , wet plugs won't fire, especially 6volt and a bit flat. A WCD Carter should have a small filter under a brass plug, in the top of the carb over the needle and seat which you can check without removing the carb or the top of the carb. . While it i out you could try blowing some air gently down through the seat from the top if you think it may be dirty, otherwise to remove the needle and seat the top has to come off the carb. Next , check the plugs, clean them in some acetone , try not to scratch the porcelain, but clean up the electrodes and reset the gap. Plug AND points gap is more critical with 6volt system. Compression test engine while they are out. Remove the distributor cap and check that the rotor is turning continuously( you could have a broken roll pin in the drive gear which will catch sometimes and slip sometimes, this will give you spark but not at the right time. (Damaged timing gears will give the same problem, but will also affect the pump delivery and compression Then while the plugs are out , put your finger in the plug hole on number one, turn the motor over slowly by hand until you feel compression coming up , then continue to turn until the timing marks line up...make sure the rotor is pointing where the number one plug lead would be on the cap??? if not timing is damaged. You said you had replaced the points and condensor then lost spark completely? Did you set/reset the gap on the old points when you put them back in the car ? You lost spark altogether with the new ones , that could have been caused by the points NOT closing, They have to close and only open to 16 thousandths of an inch ....if they don't fully close there will be no spark just as if they do not open. You can check to make sure the rotor has not shorted to earth by holding the HT lead from the coil over the rotor and cranking the engine while the cap is off, if it sparks to the rotor the rotor has earthed and is faulty, get a new one.
I'll check what I can. All I had done was drive around the block a few times and parked it. Never started again. I personally think the new points/condenser were bad as the old ones made it spark again. Gap is good. Coil tests good. The old fuel pump wasn't shooting fuel so it got rebuilt. New one pumps out gas when turning over but I will give it that minute to check the amount. Carb had been rebuilt with new gaskets and cleaned a few weeks prior as the accelerator pump had dried out. My battery is new but it took a good shit kicking and is still charging from overnight. Manifold gaskets had been recently changed. She ran and sounded great before this. Something stupid I'm sure. Let ya know if I find it!
All I could report today is fuel pump seems to be pumping the required amount of fuel while turning over. Checked the screen under the brass plug on the WCD carb and also blew through the line towards it. All seems good at that point. Plugs are clean and dry. Points are gapped at .016" or .40mm on my gauges. Should they be wet from trying to start? I will attempt a few more tests tomorrow. Sorry about the confusion on the 268 flat 8. I assumed they were exclusive to Pontiac. I'll be more specific in the future.
Pulled the plugs and stuck my finger in hole # 1 and turned the crank. Felt a fart of air so I assume the cylinder was in compression stroke. Kept turning until I hit the timing mark then pulled the cap to check the position of the rotor. #1 plug lead is about 11 o'clock and that's where the rotor was pointing. Thanks for that tip! I'm surprised on how sloppy the rotor sits on the shaft. I should order one and a cap while I'm at it anyway. I'm going to buy a compression tester this weekend. I'd like to know those numbers anyway. After that I guess it's time to check over the carb again.
It's your engine that you will have to live with. I'd be changing the oil right after I get it started and idling.
Have you checked compression in each cylinder ? I know nothing about straight eight's ,but here's what happened to me with a 35 Ford coupe and flathead v/8 . I go look at a true garage find that had been in storage since 1964 and not run.This was in about 1990 .The owner says i can make an attempt to start it,so i come prepared.Clean the points,fully charged battery,remote fuel tank and within 1/2 hour of getting there the coupe is running and i'm driving it around the neighborhood . A deal is struck, i drive it onto my trailer and bring it home. It fires right up and i drive it off the trailer and around my neighborhood,severel times ! Put it in the shop for the night ,fat,dumb and happy about my good running Ford. Next day i try to start it and no go. I do all the same things as you.Points plugs condenser fuel pump recheck the timing a hundred times and still no go! turns out a bunch of valves had stuck open overnight due to either some rust on the stems,gunk in the guides,faze of the moon or curvature of the earth. Whatever it was i overlooked that possibility because it had run so well less than 24 hours prior.A few years after the same thing happened with a willys super hurricane 6,although that on had sat for a few weeks. This time i knew what the problem was and had it back running in a jiff. True story,for what it's worth
Do you have Spark at the points? Next check each wire at the Spark Plug end. For the umpteenth time I found a Rotor burnt through from the rivet that holds the metal Tang to the inside mount relief. That lets the Coil spark short direct to the Dist shaft and no spark gets to the plugs. Car owner thought it was Fuel related also,,,,, WRONG. The Wizzard
An oil change it is. Wow, stuck valves what a story. Still need to buy a compression tester. I only tested one plug for spark. I will check them all when I get them back in. Thanks for all your suggestions and stories!
Here's my dry compression test today: #1 - 110 lbs #2 - 110 lbs #3 - 105 lbs #4 - 100 lbs #5 - 110 lbs #6 - 95 lbs #7 - 100 lbs #8 - 110 lbs Not overly concerned about wet and besides I don't have an oil squirt can available. I will be picking one up. Not surprised at the those readings. #6 plug was the blackest. Is it safe to say no valves are stuck until I test wet? I rechecked the timing with the "finger in the #1 hole" test and the rotor is pointing at the correct position after lining up the timing mark so I hope that indicates it's timed. I'm going to order a new cap and rotor for next week and recheck spark on all plugs before I tear at the carb. I also removed the fuel line when compression testing to keep out any further fuel in the crank. Thanks again for those tips gang!
I wouldn't worry about doing a Wet test. You have plenty compression for the motor to run just fine. You don't have any valves standing open. Also prior to changing the Cap and Rotor I'd test for spark at each plug end of wire. Then you'll know if you even need to change them. The Wizzard
I did a wet test before your message but still respect your opinion. Basically like you were saying all it did was raise the psi around 15-20 psi. Worn rings here and leaky valves there maybe but no bells going off. Time to spark it up!
Still no start so I decided to rip the carb apart again. Oh no! My nice clean carb! Sediment everywhere! Cleaned it up, blew air through the passages and sprayed some Seafoam around. I had drained the gas tank way back to change an inline filter at the tank. I only drained it as far as the gas line level because I was scared to take the drain plug out in case it stripped or something and replaced with fresh fuel. Screw that. I drained the entire tank through the drain plug and couldn't believe how dark and black with dirt it was! Disgusting! I then used a gas can as my tank and ran the rest of the bad gas through the line. Hooked everything back up and she fired again after many turnovers then replaced the oil. It now runs on it's own again. Here's what I think happened. I've only been moving the car in the driveway. It was after a couple runs around the block the car never started again after that. I must have churned up the shit in the tank enough to pollute the carb. I had wondered why the PO had 2 inline fuel filters, one at the tank and another at the carb. I had removed one thinking it was an overkill. Looks like a new tank and fuel line is in order. I now have another issue which seems to have happened after all of this, which I find hard to be related. Being not forum savvy, Do I continue with my new problem/question here or start a new post? Still happy it's back to life and learned a few new things on the way.
Ya I thought so. I believe it's not related. Guess the problem with this post was really bad/contaminated gas resulting in a plugged up carb. I think the gas tank was original although it looks like it was removed at one time by the looks of the straps. How old the gas was is beyond me.
So what did you do to get it running again? I have the Pontiac Straight 8 and seems that one cylinder has ZERO compression - must be stuck valve... Any help appreciated. Took to a guy who knows but he wants to do a valve job or an engine rebuild. BIG $$$
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