No Spark on #2

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The 68 I just purchased was running really bad so I replaced the plugs, wires, cap, rotor. I still have no spark on #2. Any ideas? I have a new point set but haven't installed it yet but I didn't think points would be cylinder specific. I narrowed it down to #2 by pulling the plug wires one at a time while the engine was idling and there was no change when the #2 wire was removed. Any pointers would be appreciated.
 
What did the orignal plugs look like? Was #2 differnt? How about #2 on the cap? Do you have a dwell meter? I have never heard of it but maybe the lobe for #2 is worn? I would think you would see that on a dwell meter as a jump in the needle. Also could be shot bushings on the shaft and it just happens to bounce away on #2 for some reason. Again I would think that would show on a meter. You may have to pull the dizzy to tell for sure about the shaft/bushing wear. Dwell should be steady maybe +/- 2 at the most.

You should confirm lack of spark with a timing light or spark checker it could be low compression is why you dont notice a dif when you pull #2
 
I swapped plugs from 1 to 2 and trouble stays on 2. I've pulled the wire and can hear the spark arcing from the wire to the plug. 2 is dead. Starting to think it's a valve problem.
 
Funny you should say that. Just finished and #2 has a bad leak on the exhaust valve. I have ~180 lbs on the other 5 and barely get the needle to move on 2. You can distinctly hear a pulse from the exhaust with the gauge in 2 whereas there's no pulse from the other 5. Checked compression on semi warm engine with all plugs removed. About to pull the valve cover and see whats up. I guess the next step is to pull the head.
 
David,

You may want to see about upgrading heads to a leter model assuming you don't already have one. See the sticky at the top of the forum. After all if you are going to go through the trouble of pulling the head you might as well upgrade!
 
Good news! Found the problem as soon as I pulled the valve cover.





The push rod is also bent. Could be why it came out.
 
with mine i had a problem that a pushrod had bent with the previous owner. After he replaced the rod, he didnt check the lifter which had broken and could have possibly spewed pieces all in the piston and could have destroyed alot of the insides. Lucky for me though after checking all the insides though after taking apart the engine i found that everything was ok apart from the gunk and the lifter.

Did you have any problem like that with yours?
 
I picked up a new pushrod at AZ. When I started it back up there was some clicking then the miss started again. I quit working on it after that. I'll get back on it tomorrow after work. Any other ideas? It was running fine a few days ago.
 
addo":29m7ci9q said:
Possibly a bent or stuck valve is causing the pushrod hassles.
sounds likely! pushrods dont usually fail if the rest of the valve train is in good health, but they are designed to be the weakest link when something goes wrong, kinda like a fuse.
sounds like pulling the head is in order. as you have it off, you might as well check out all the valves, seats, the whole works
good luck--josh
 
A few years back I bought a 67 Mustang that had sat for a number of months. It would run but barely. After I towed it home and pull the valve cover discovered that it had water/antifreeze in the oil and that it had a number of bent push rods. Pull the head and discovered that it was cracked and that the hydraulic lifters were seized on the cylinders with the bent push rods. The lifters were seized so badly that you could not compress them at all.

Not sure what causes lifters to seize, maybe overtime the oil leaks out of them and in my case the moisture in the oil caused them to rust internally. I bought a new head and replace all the lifters and push rods and was good to go.
 
The 250 in my car did the same thing. It had been sitting for about 12 years when I bought it. Had seized exaust valves on cylinders 1, 3 and 6. I pulled the head and installed all new lifters. I took all the valves out of the head, cleaned them up, re lapped them in and installed new valve seals. I then put all new push rods in. That was a year and a half ago. This engine is driven daily and haven't had a problem out of it in the over 14,000 miles since then.
 
Now it's really weird. The valves aren't binding at all and now I have good compression in #2. Now I'm trying to find my magnet to see if something was dropped down the carb and found its way into the cylinder. The way the carb looks it's entirely possible.
 
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