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Old 04-03-2020, 01:17 PM   #51
Grumpy old man
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Re: Is it timing, carburetor or something else?

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Originally Posted by maverickmk View Post
Jesus Christ, WTF is wrong with some of you and your thin skin? I simply said I'm not sure why. Good lord, some of you need to step away from the computer and get some perspective. You're the second guy to get their panties in a wad because I was trying to gather some info or be helpful.
Nobodies trying to be that guy, there are just a lot of easy cheap "old school" tricks to diagnose/eliminate problems before tearing the head off . These old 6 cylinders will run forever with basic maintenance .
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Last edited by LockDoc; 04-03-2020 at 02:59 PM.
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Old 04-03-2020, 05:53 PM   #52
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Re: Is it timing, carburetor or something else?

Having reviewed the videos you posted I am even more convinced you are experiencing some valve sort of train problem (You may have more than 1 problem.) See linked video below.


https://www.google.com/url?sa=t&sour...CMxCVO2Pn_nkr4
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If it breaks I didn't want it in the first place
The WMB repair thread http://67-72chevytrucks.com/vboard/s...d.php?t=698377
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Old 04-07-2020, 05:43 PM   #53
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Re: Is it timing, carburetor or something else?

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Originally Posted by Steeveedee View Post
That's a good observation. I noticed a lot of slag(?) on plug #6's seat. Maybe it has the wrong plugs.

OP- Add a pic of the head where the plugs screw in, we can verify what plug type is proper.
Pic of the plug hole:
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Old 04-07-2020, 06:13 PM   #54
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Re: Is it timing, carburetor or something else?

That looks like a tapered seat to me, but it can't possibly be sealing with the plug from the looks of it. In fact, that would be why that plug looks so bad- it isn't making clean enough contact to seal or fire reliably. So, just one piece if the puzzle. Like HO455 says, the valve train needs addressing as well.
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Old 04-10-2020, 12:28 PM   #55
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Re: Is it timing, carburetor or something else?

I had hoped by now, someone else would have commented.

That spark plug hole in the picture is so dirty, I can't say I have any idea what I am looking at. I had thought about pulling a plug out of my 292 and taking a better lite picture to compare, but questioned if I really wanted to spend the effort for this thread.

With two craftsman spark plug sockets in hand, the 5/8" socket fits the installed R44TS plug as it should. The 13/16" spark plug socket will not come close to fitting the machined pocket for the spark plug.

The machined pocket in my head for the tapered plug measures 1". My 13/16" plug socket has an OD of 1 1/16".
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Old 04-10-2020, 01:27 PM   #56
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Re: Is it timing, carburetor or something else?

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Originally Posted by RichardJ View Post
I had hoped by now, someone else would have commented.

That spark plug hole in the picture is so dirty, I can't say I have any idea what I am looking at. I had thought about pulling a plug out of my 292 and taking a better lite picture to compare, but questioned if I really wanted to spend the effort for this thread.

With two craftsman spark plug sockets in hand, the 5/8" socket fits the installed R44TS plug as it should. The 13/16" spark plug socket will not come close to fitting the machined pocket for the spark plug.

The machined pocket in my head for the tapered plug measures 1". My 13/16" plug socket has an OD of 1 1/16".
I bought tapered plugs with the 5/8" size.
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Old 04-10-2020, 03:52 PM   #57
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Re: Is it timing, carburetor or something else?

Then you have the correct type of plug. Guess I could have added that to my previous comment. Try cleaning the seats and plugs and reinstall the plugs. The seats should be clean metal. See if that improves how it runs.
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Old 04-10-2020, 06:58 PM   #58
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Re: Is it timing, carburetor or something else?

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Originally Posted by Steeveedee View Post
Then you have the correct type of plug. Guess I could have added that to my previous comment. Try cleaning the seats and plugs and reinstall the plugs. The seats should be clean metal. See if that improves how it runs.
Will do. Thanks.
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