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Missing on one cylinder - 351C
So, I don't know the source of your problem, but I would pull the valve covers and verify that you don't have a bent pushrod or a lobe on the cam that is wiped out.

I pulled the intake of a BBC looking for "a screw that fell down the carb" per the PO and when we started looking it was a big old hunk of plastic wedged up in the intake port.

If you can't find an electrical demon, then it is time to pull the valve covers and possibly the intake.

[Image: 1_01_07_15_8_53_18.png]

"I love my Hookers!" and "Get some Strange" probably have a different connotation to non automotive enthusiasts!
[+] 1 user Likes Jeff73Mach1's post
Just trying to come up with a way where you can show compression on a compression test, but not have valve seal on a running engine. It would require a combination of problems. I can think of two scenarios, both that involve a collapsed or bled down lifter when the valves were adjusted. In one, the rocker was screwed down too far to compensate for the lifter, and in the other, the valve has recessed. Then, when the engine is started the lifter pumps up enough to keep the valve from closing all the way.

It appears that the spark plug is not the problem, and it would take a really big leak on the intake manifold to lean that cylinder out enough for that cylinder to not fire, or suck enough oil to foul the plug.

Be interesting to find out what the problem is, file it away for future reference.

“If you can't explain it simply, you don't understand it well enough.”
--Albert Einstein
[+] 1 user Likes Don C's post
As a "Hail Mary" if it has double springs, check to see if the outer spring is broken. I had it happen once. The inner saved the engine. It was missing because the valve was bouncing off the seat. As I said a very long shot. I hope you get it sorted out with minimal drama. Chuck
[+] 1 user Likes c9zx's post
Pulled off the intake. The one thing that jumps out at me is that one port around the problematic cylinder. There isn't a bunch of gasket stuck to that port in the intake, so I have to assume it's blown out. Ran out of light to do anymore today

In nothing else, looking forward to cleaning this up and replacing those nasty valve covers. 

[Image: cnmkXNPigsSCmyvO8Bbxo_t-LPr0k_zkMFpw2_TH...50-h937-no]

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Hey Dude,
That is sounding like a best case scenario
What of the broken bolt? were you able to remove it with the manifold off ?
Kind of sounds like the previous owner did away with the valley pan (turkey pan)
Could you please tell us what intake manifold you have, aluminum or cast iron and manufacturer.
I prefer to use Felpro sfl1228 with no valley pan if the intake does NOT have the heat crossover.
Typically, I will NOT use the end seals, I instead like to use permatex grey.
Unless you know if your engine block has been decked and or if your cylinder heads have been shaved, this can be a safer route to prevent oil leaks.
Please bear in mind that the intake manifold, could have been machined to fit a machined block and or cylinder heads.
The standard rule for clevelands seems to be no more than 0.030'' taken off of the block and or heads as a total will still seal with thick aftermarket gaskets such as the Felpro I listed ( 0.060'')
Now that you have the intake off you can easily do a much better inspection of the valve train.
with a cheap dial caliper you can measure your camshafts lobe lift on that #1 cylinder and compare it to the lift of the other cylinders.
That will tell you if the cam is good or not and give some kind of idea as to how much VALVE LIFT your cam is supposed ho have.
To measure camshaft lobe lift you simply need  to measure the height of the lifter at it's lowest point and again at it's highest point while rotating the engine by hand and do a little math.
How about some pictures of your lifters of that #1 cylinder at their lowest and highest lift with some measurements ?
Some here will also be able to tell you a lot about the state of your valve lash with some good pictures of the lifters at the valve fully closed and fully open positions.
Dude, it is my opinion here, that you not move too fast or haste fully, look, measure, report and get opinions here and proceeded slowly.
Sorry I am so anal, but I only want you to get this problem repaired properly and have great results.
If I were in your area, I would gladly lend a hand free of charge.
P.S. there are a few members here that think you may have a collapsed lifter on that # 1 cylinder , I myself would not rule that out just yet, but let's make sure that your cam is not wiped out before we get into valve lash adjustment.
[+] 1 user Likes boilermaster's post
Dude, I literally just went through all of this if you’re going through with my Cleveland. Come to find out I had a wiper lobe and a solid roller lifter had disintegrated and messed up a piston skirt. I needed to go through my engine anyway so I’m in the current process for a rebuild.
I would strongly encourage leak down test. I am surprised that no one has recommended this yet. You can get a testing device off Amazon for less than 100 bucks. This will really help you narrow it down.
You can also use it to test the health of all other seven cylinders.
It will isolate your issue hopefully.
It can, but not always.

I had 150 pounds Compression on my bad cylinder. Anyway, I hope you don’t have the same issue that I did. My prayers are with you. Keep us updated


Sent from my iPhone using Tapatalk
[+] 1 user Likes mikeyhunts's post
Boilermaster, great info as usual. 

You can probably see the end of the bolt in the pic below. The end of the bolt is sticking out past the end of the thread so I'm hoping I might be able to grab the bottom of it to work it out. Either way, it looks like I can go try to work it either direction which should make life a little easier. Haven't been back out to it since last night. 

You are correct, there is no pan in there. Manifold is an Edelbrock Torker 2. Thanks for the tips in gaskets and sealing. 

I'll have to look at what it would take to measure the cam like that. I certainly would like to have that info, but not sure how to go about doing that. I'll get some more pics once I get going on this. Very time limited lately so this will be a bit here and a bit there. Now that I've parked it, I'm going to take my time and go through this and do my best to do it right and learn as much as I can while I'm here. 

And Mike, you really had to go there?  Wink If this engine needs a rebuild, so will my marriage. Here's to hoping I don't follow along your path. 

[Image: Wtigg_95qBCYehIdMlSv3_H2G8f1PEyFGg2WowXJ...08-h889-no]
Sorry to mention it.
I can relate with the wife!

Sent from my iPhone using Tapatalk
[+] 1 user Likes mikeyhunts's post
That's definitely a big enough leak to cause enough oil to quickly foul the plug, as well a making it too lean to fire before it starts sucking in oil.

With that much of the gasket missing I would want to make sure it isn't stuck in one of the valves.

I think Chuck (c9zx) also had this kind of failure.

“If you can't explain it simply, you don't understand it well enough.”
--Albert Einstein
Just realized that those last pics I posted probably weren't showing up. Should be working now.
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