It may be time to have a friend with mechanical knowledge look at it with a fresh set of eyes.
Cylinder has spark but not firing..
- Thread starter duey_roc
- Start date
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..........check to see if 1 of the unused bolt holes is sucking air at the carb base.........kim...
Dartnut
Don't hate me because i'm beautiful
Do you have a factory service manual?
That would be your next thing to buy.
Seeing that you have ''experimented'' a lot with this engine, it's no wonder that you are having problems with it.
The running a hydraulic lifter on a solid cam experiment and pulling the intake off twice because of vacuum leaks speaks volumes to me that you don't know what you're doing.
I bet that your problem is a mechanical one, and it is probably the cam, lifters, push rods, or rockers are mis matched, installed incorrectly, or worn out.
You must have stock in a gasket company or something........lol
Hyper_pak
Old School Chrysler Fan
I had a 67 440 with the same problem. Turned out to have 1 valve longer that the others. On a compression check all was ok, but when lifters pumped up it would push the valve off the seat and leak off all the compression. Put a straight edge on your valves and see what the installed height is across all the stems.
first off you need to buy a Ohm meter like Rusty said above.You can get a volt/Ohm meter at any parts store for 10 or 15 bucks. now check the Ohm readings........What are they???? I had a bad set of wire that required me to keep changing out due to growing High Resistence. i didn't make me loose a cyl......not at idle but under load it would cause a popping noise. check the wires, replace the bad one and off i when again. After a year of this silly game. I bought a high Q wire set. no more problem.
PLEASE DO WHAT RUSTY AND I HAVE SUGGEST BEFORE YOU GO ON! One step at a time will get you there.
Now it is possible that the valve job was not done properly,(as Hyper pak sugested) causing this problem. it also could be that with the heads being shaved that the push rod is on the raged edge of being to long now and on cyl #1 and 8 they are two long.
The block that i had square decked (cut the deck to be square with the crank) was lowest at #1 and at the rear #8 before it was decked.
duey_roc
Well-Known Member
Ok let me make something clear here. No, i dont know more than probably any of you guys on here about motors but i know enough about them to get them running and running well. I've never had this problem before which is exactly why I'm coming to you guys about this. I am mechanically inclined enough to solve this issue. :banghead:
I have good compression in all 8. #2 and #8 cylinders are giving me problems. I do have spark. I just did the heads on this motor. I know it's not a few valves being larger because I had another set of heads on the motor and the same 2 cylinders were doing the same exact thing.
I HAVE had two people look at the motor that were more mechanically inclined than me and they both said intake problem. Here's why I'm agreeing with them...
First off an intake manifold crack would cause a vacuum leak. The crack is not on the outside. I know this because i sprayed carb cleaner around the intake while the motor was running and i had no sudden climb in rpm. The crack must be underneath the intake, possibly around the runners. This would explain why my air mixture screw on my Holley is not tuning. You can screw that mixture needle in alllllll the way and the motor has no changes. This would ALSO explain why my exhaust burns your eyes when you stick your face around the tail pipes.
I searched Google on symptoms of a bad intake manifold. This one website explained that a cracked or warped intake manifold would not affect compression, it would act like a vacuum leak, and it may in some cases give you a misfire. In this situation, a misfire in 2 of my cylinders. I can understand why my intake would have a crack because it's an LD4B intake manifold. These intakes were made back in the 60's and 70's for the 273 and 318 motors if im not mistaken. In other words, Its OLD. I can understand it being warped or cracked.
Now.... does anyone else have any recommendations or ideas? :happy1::coffee2:
I have good compression in all 8. #2 and #8 cylinders are giving me problems. I do have spark. I just did the heads on this motor. I know it's not a few valves being larger because I had another set of heads on the motor and the same 2 cylinders were doing the same exact thing.
I HAVE had two people look at the motor that were more mechanically inclined than me and they both said intake problem. Here's why I'm agreeing with them...
First off an intake manifold crack would cause a vacuum leak. The crack is not on the outside. I know this because i sprayed carb cleaner around the intake while the motor was running and i had no sudden climb in rpm. The crack must be underneath the intake, possibly around the runners. This would explain why my air mixture screw on my Holley is not tuning. You can screw that mixture needle in alllllll the way and the motor has no changes. This would ALSO explain why my exhaust burns your eyes when you stick your face around the tail pipes.
I searched Google on symptoms of a bad intake manifold. This one website explained that a cracked or warped intake manifold would not affect compression, it would act like a vacuum leak, and it may in some cases give you a misfire. In this situation, a misfire in 2 of my cylinders. I can understand why my intake would have a crack because it's an LD4B intake manifold. These intakes were made back in the 60's and 70's for the 273 and 318 motors if im not mistaken. In other words, Its OLD. I can understand it being warped or cracked.
Now.... does anyone else have any recommendations or ideas? :happy1::coffee2:
fishy68
Tyr Fryr's Inc.
Since you seem to have your mind made up that it's a cracked intake why are you still asking for recommendations? Take it off and examine it.
kman521
Well-Known Member
What is the resistance of the #2 and #8 plug wires?
Check the simple stuff first.
It is possible to have a plug wire that won't fire a spark plug under compression if it has too much resistance but you can still get a shock off it.
Check the simple stuff first.
It is possible to have a plug wire that won't fire a spark plug under compression if it has too much resistance but you can still get a shock off it.
only trying to help, not offend :dontknow:
duey_roc
Well-Known Member
Ive switched up everything. New cap, rotor, plugs, wires... and ive switched everything up to different cylinders as well. Still getting the same issue. And i know youre trying to help man and im super appreciative!
rayer: but some ppl just come off as goddy and it gets old. Im not mechanically inclined? cool ill sell my car and go play video games. Thats better.
Oklacarcollecto
Life is an experiment
Ive switched up everything. New cap, rotor, plugs, wires... and ive switched everything up to different cylinders as well. Still getting the same issue. And i know youre trying to help man and im super appreciative!
Keep in mind that most of the time you keep getting the same comments, they are coming by drive by posters that didn't read the thread. It is just a fact of life on the internet so you just have to ignore them and move on.
It would pay to pay attention to people that have been following and reading the whole thread. If a new poster has a new idea that hasn't been explored then that is a different situation.
67Dart273
Well-Known Member
The reason some of us are on your *** is because you have not indicated that you've taken any real steps, other than "throwing ideas" at the problem.
Your theory that "just because it's old" it's probably cracked does not hold water, no pun intended, neither does your thinking that this is a hidden crack. It might be, but very doubtful
LOOK at this photo of an LD4b:
The cylinders that are paired by the hidden, underlying port runners are 1 - 4 - 6 - 7
On the other side, the UPPER runners are 2 - 3 - 5 - 8 which are on TOP of the lower, hidden runners. How is there going to be a "hidden" crack?
And........if there's a crack in that side, why is only 2 and 8 giving you trouble which are separated at far ends of the engine?
Why wouldn't it be 5 and 8 which are on the same runner?
Or why not 2 and 3, which are on the same runner?
Now anything is possible. But a "warped intake" leaking from the oil gallery would normally show "burning oil" as it's sucking crankcase gases from the valley
Your theory that "just because it's old" it's probably cracked does not hold water, no pun intended, neither does your thinking that this is a hidden crack. It might be, but very doubtful
LOOK at this photo of an LD4b:
The cylinders that are paired by the hidden, underlying port runners are 1 - 4 - 6 - 7
On the other side, the UPPER runners are 2 - 3 - 5 - 8 which are on TOP of the lower, hidden runners. How is there going to be a "hidden" crack?
And........if there's a crack in that side, why is only 2 and 8 giving you trouble which are separated at far ends of the engine?
Why wouldn't it be 5 and 8 which are on the same runner?
Or why not 2 and 3, which are on the same runner?
Now anything is possible. But a "warped intake" leaking from the oil gallery would normally show "burning oil" as it's sucking crankcase gases from the valley
duey_roc
Well-Known Member
Flip that intake manifold over. On the ends of the intake manifold is what im thinking. Where the runners are. That would be in a place where it could be sucking crank case pressure which would be a vacuum leak as well. Im not dogging that just because its "old" it doesnt work. This intake had a crack in the water jacket when i first got and had to get it welded back. Whose to say there isnt another crack?The reason some of us are on your *** is because you have not indicated that you've taken any real steps, other than "throwing ideas" at the problem.
Your theory that "just because it's old" it's probably cracked does not hold water, no pun intended, neither does your thinking that this is a hidden crack. It might be, but very doubtful
LOOK at this photo of an LD4b:
The cylinders that are paired by the hidden, underlying port runners are 1 - 4 - 6 - 7
On the other side, the UPPER runners are 2 - 3 - 5 - 8 which are on TOP of the lower, hidden runners. How is there going to be a "hidden" crack?
And........if there's a crack in that side, why is only 2 and 8 giving you trouble which are separated at far ends of the engine?
Why wouldn't it be 5 and 8 which are on the same runner?
Or why not 2 and 3, which are on the same runner?
Now anything is possible. But a "warped intake" leaking from the oil gallery would normally show "burning oil" as it's sucking crankcase gases from the valley
67Dart273
Well-Known Member
OK so now you've changed your story. Wish ya luck. Bye.
duey_roc
Well-Known Member
This doesnt change anything man. All i said was this intake had a crack when i first got it and then i got it fixed. I had this intake on my old dart sport and it was working. And now I believe this intake is done. Its been off and on 6 or 7 times. Ill let everyone knows what happens when i take the intake off and change it out.
Inertia
Well-Known Member
I was going to add this about 25 posts ago..
Are the intake manifold locator pins still in the block, .. they're in the middle, both front and back, to centre the manifold..
Does the manifold have the holes for the pins to go in...??
Seen a few manifolds with little dimples in the bottom.,, where people didn't remove the pins,,
They hold the manifold up, so it doesnt seal., sucks vacuum from the valley on the sides, and also leaks oil out the back like crazy..
Are the intake manifold locator pins still in the block, .. they're in the middle, both front and back, to centre the manifold..
Does the manifold have the holes for the pins to go in...??
Seen a few manifolds with little dimples in the bottom.,, where people didn't remove the pins,,
They hold the manifold up, so it doesnt seal., sucks vacuum from the valley on the sides, and also leaks oil out the back like crazy..
duey_roc
Well-Known Member
Ya those are gone. :blob:
/6 Matt
30 Degrees Crooked
After reading through this whole thread, I find myself reminded of a member by the name of "Cowboy."
Diagnostic skills never come to some...
Diagnostic skills never come to some...
kman521
Well-Known Member
Ive switched up everything. New cap, rotor, plugs, wires... and ive switched everything up to different cylinders as well. Still getting the same issue. And i know youre trying to help man and im super appreciative!
If I came off the wrong way I apologize for that.
I have been following this thread from the beginning so I'm not a drive by poster.
I have just finished reading through this thread again and no where can I find a post where the wires have been swapped or replaced earlier in this thread. If I have missed it again shame on me but It wasn't mentioned before.
You mentioned that you were going to remove the valve covers and check to make sure the valves were moving, has that been done?
Yes I know the compression tests good but have you done this?
Good luck,
Woods74
Broke Senior
3 pages? Really? C'mon dude. Give me fuel, give me fire, give me that which I desire. Stop pissing everyone off acting like a kid, follow the procedure, double check your work, make it run.
Done deal.
Done deal.
duey_roc
Well-Known Member
Yes. I've made sure they're moving. Everything is working as it should be. That was also a test I did on Saturday. I removed the wires and tried new ones.
BWAHAHAH! Really dude? If this thread, is "pissing" you or anyone else off, you need to find a different thread to post in. Dude is asking for help, if you don't want to offer help, then move along. Stop treating this guy like hes a child, with your own childish behavior. And to "67Dart273" it was cute you said bye!
hollywood hig
King of the assklowns
i've been reading this post for a few days.....if u think it is a manifold problem i would think that a vacuum test w/a gauge would be in order.
should be a wealth of information with that gauge, and they are not expensive.
like rob said earlier, one step at a time.......sometimes on a thread like this u will get alot of info, good stuff, but sometimes too much.
good luck dude, i'm sure you'll figure it out.
higgs
should be a wealth of information with that gauge, and they are not expensive.
like rob said earlier, one step at a time.......sometimes on a thread like this u will get alot of info, good stuff, but sometimes too much.
good luck dude, i'm sure you'll figure it out.
higgs
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