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Some of the lifters do seem to be pushed farther into the lifter bores than they should be. I have not tried to pull any out, though.
They will be different depths in the bore depending on the cam lobe position. If the cam is wiped normally the bottom of the lifter get's mushroomed and they are really hard to get out. A bit tight pulling out isn't abnormal though.
 

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Discussion Starter #242
And the rocker arms are completely removed?


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Yes, sir. Even pulled the pushrods completely out and placed them on a shelf in the order they came out. All of them are perfectly straight.
 

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Discussion Starter #243
Here are links to video of #4 and #6 cylinders with compressed air connected to them and no rockers or pushrods installed.



#6 is much more pronounced than #4 but I'm thinking maybe because #4 is farther down in the bore. Doesn't really make sense, as there should be NO leakage around the valves, much less enough to move paper.

I was in my garage with all doors closed and no air movement whatsoever.

All of the air sound is coming out of the intake ports, there is no leakage from the hose or compressor.
 

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It seems like for the air to be rushing out of intake and/or exhaust ports during a leak down test (with rocker arms removed from the valves) would point to stuck... or bent valves. It appears that something went downhill with the engine pretty quickly after your initial compression test.

What is strange is you were not messing with... or adjusting the valve train. I recall that early on in this discussion you mentioned that you were having a hard time seeing the timing mark at idle. And then later on, you mentioned hearing a "metal to metal" contact noise while cranking.
This is only a guess, but I'm starting to think something is not right with your timing chain and... or crank/cam gears. Another possibility that might explain the strange sequence of engine events might be a sheared keyway in the crank snout. Both of these situations could cause a misalignment in the valve train and possibly lead to a piston-valve contact.

Tearing down the engine is probably the wisest step at this point. When you remove the heads, inspect all of the pistons for any signs of valve contact... and be sure to pay close attention to all of the components behind the timing case cover.
 
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Discussion Starter #245 (Edited)
It seems like for the air to be rushing out of intake and/or exhaust ports during a leak down test (with rocker arms removed from the valves) would point to stuck... or bent valves. It appears that something went downhill with the engine pretty quickly after your initial compression test.

What is strange is you were not messing with... or adjusting the valve train. I recall that early on in this discussion you mentioned that you were having a hard time seeing the timing mark at idle. And then later on, you mentioned hearing a "metal to metal" contact noise while cranking.
This is only a guess, but I'm starting to think something is not right with your timing chain and... or crank/cam gears. Another possibility that might explain the strange sequence of engine events might be a sheared keyway in the crank snout. Both of these situations could cause a misalignment in the valve train and possibly lead to a piston-valve contact.

Tearing down the engine is probably the wisest step at this point. When you remove the heads, inspect all of the pistons for any signs of valve contact... and be sure to pay close attention to all of the components behind the timing case cover.
Well, this will throw another wrench in the works.

I pulled the passenger side head off, since the number two cylinder is kind of what started all this and, guess what, nothing seems out of line except a spot on the #2 head gasket that was probably the cause of the lower compression on that cylinder. It almost looks like there was something in between the head and the block when it was put together. There is a corresponding mark on the head.

When I was checking for TDC on cylinder #1, I lined the mark on the dampener up with the 0 mark on the tab and stuck a screwdriver in the plug hole and I could definitely feel the piston.

When I pulled the passenger side head, #6 is at the top of the bore, which would confirm that the timing mark is good.

The next puzzler is that the valves, pistons and cylinder walls all appear to be in good shape, other than a good coating if carbon from it running so rich.

There is a light scratch on the dome of the #6 piston, but it looks fresh so I am pretty sure that it came from the head when it broke loose and moved some.

Here are some pics. Maybe some of you with more expert eyes can pick up something that I don't see.
 

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Discussion Starter #246
Also, a shiny cam is not a ”wiped“ cam. When a cam goes bad it is usually enough to easily feel with your fingernai.
The cam lobes feel smooth to the touch, at least the part that is showing in the valley.
 

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Yes, sir. Even pulled the pushrods completely out and placed them on a shelf in the order they came out. All of them are perfectly straight.
The cam is probably fine. The good news is you needed to pull the head, that gasket looks like it was damaged on installation. Now it’s time to pull the valves out of the head and see what the seats look like. How deep are the marks in the head and block? That may cause a sealing problem. You may end up pulling the cam just for identification.

Is that corrosion in the the #8 cylinder wall? Hard to see in the picture.
 

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Discussion Starter #248
The cam is probably fine. The good news is you needed to pull the head, that gasket looks like it was damaged on installation. Now it’s time to pull the valves out of the head and see what the seats look like. How deep are the marks in the head and block? That may cause a sealing problem. You may end up pulling the cam just for identification.

Is that corrosion in the the #8 cylinder wall? Hard to see in the picture.
Fortunately, the only damage I see or feel is limited to the head gasket. The actual mating surfaces of both the head and block wiped clean and are almost perfectly smooth. I say "almost" because when I run my fingernail across it, I feel a very slight imperfection but it feels more like it is raised than it does a gouge in the metal. I am pretty sure it is just carbon that built up in the area where the gasket was bunched up. I was able to scrape some of it off with my fingernail.

I checked #8 and did not see any corrosion at all, just the carbon coating.
 

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Ok good. I am not sure what you were doing on the leak down test. You could see If the chamber will hold mineral spirits to get a quick idea of valve sealing.
 
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Have you checked the float levels on the carb bowls? Sometimes we neglect the obvious. If you have a leaking needle/seat this will show it.

Another option is borrow a carb from someone. From reading all the posts it is not clear to me if you have a carb issue, ignition issue or cam problem. Eliminating issues one at a time makes life less complicated.

Good luck
 

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Discussion Starter #251
Have you checked the float levels on the carb bowls? Sometimes we neglect the obvious. If you have a leaking needle/seat this will show it.

Another option is borrow a carb from someone. From reading all the posts it is not clear to me if you have a carb issue, ignition issue or cam problem. Eliminating issues one at a time makes life less complicated.

Good luck
Carb is a brand new 850DP and the fuel level is set at the bottom of the glass sight plugs.

Ran the same with the new carb as it did with the old.

Engine is torn down with the intake and passenger side head off now which revealed a bad head gasket on #2. That cylinder did have low compression compared to the others. It was at 135# while the others were around 180.
 

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Discussion Starter #252
Ok good. I am not sure what you were doing on the leak down test. You could see If the chamber will hold mineral spirits to get a quick idea of valve sealing.
I am baffled by the air blowing out of the intake ports, as well. At this point, it was more of just a pressure holding test than a leak down test. Unless we are missing something obvious, I can't explain it.

With the valves both closed, the cylinder should hold pressure pretty well. There is nothing I can think of, except possibly the valve seats not allowing a good seal, that would allow air to blow out through the intake ports. Even a bad valve seat should not allow the volume of air to escape that you see in the videos.

Are you saying to turn the head upside down and pour mineral spirits in the chamber with the valves and see if it leaks out around them?
 

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Discussion Starter #253
Just out of curiosity, does anyone care to venture a guess at the compression ratio this was making? I am pretty sure the heads have 119cc chambers and the domes on the pistons look pretty big. Had to be pretty high compression.
 

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Just out of curiosity, does anyone care to venture a guess at the compression ratio this was making? I am pretty sure the heads have 119cc chambers and the domes on the pistons look pretty big. Had to be pretty high compression.
Any numbers on the piston top to indicate what they are? Dome cc's
 

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I am baffled by the air blowing out of the intake ports, as well. At this point, it was more of just a pressure holding test than a leak down test. Unless we are missing something obvious, I can't explain it.

With the valves both closed, the cylinder should hold pressure pretty well. There is nothing I can think of, except possibly the valve seats not allowing a good seal, that would allow air to blow out through the intake ports. Even a bad valve seat should not allow the volume of air to escape that you see in the videos.

Are you saying to turn the head upside down and pour mineral spirits in the chamber with the valves and see if it leaks out around them?
Yes. Or just pull a few valves and take a look then go from there.
 

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Yes. Or just pull a few valves and take a look then go from there.
You could make some plates with gaskets to fit each port with a connection for compressed air and pressurize each runner behind the valve and spray something, wd40 carb cleaner even water on the valves so you can visualize what is released. Or take them to a machine shop and take your lumps. I agree the video showed much more than I would expect from the visuals of the heads. Interested in what you do and find.
 

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Your local parts store probably has a valve compressor you can borrow. Pop a few valves out and show us.
 

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Discussion Starter #259
Your local parts store probably has a valve compressor you can borrow. Pop a few valves out and show us.
If I pull all the valves out and none of them are bent and the seats check out to be in good shape, what would the next step be?

The cylinder walls look like they are in good shape, along with the pistons. I did find what looks to be a nick in the top of the #2 piston but it definitely is not new. I did not even notice it until I wiped all of the carbon off of to look for numbers. It is shaped like the edge of a valve might have hit it at some point.

If everything looks like it's in good shape, should I clean everything up and put it back together with new gaskets and see what happens?

Or should I go ahead and pull the other head off and check that side out, as well?
 

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If they look ok I would replace the head gasket and reinstall. If you really want to know what the cam is, and I would, now is the time to pull it out and see what you have or what you want. You may want to wait to install the head as your spring requirement may change if you want t o change cams. You can do the other head on the car.
 
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