Barn find engine knock (1 Viewer)

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JDS

Joined
Jul 18, 2019
Threads
9
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59
Location
Saint Louis
Hey all! Need help diagnosing an engine knock.
I bought this fj 40 with 2f engine from behind a Montana barn.
Was sitting outside unused for 10 years. 114k miles. 1981 fj40. All original.
So I did all the usual when starting after storage. Rebuilt carb. Fuel Tank , filters and lines cleaned. Marvel oil in each cylinder. Ran till warm with an added quart of Marvel Oil in the crankcase. Heard a consistent loud ‘knock,knock,knock’. Seemed louder than just valve ‘chatter’ .
Then checked Oil pressure. It was consistent and strong 50+ lbs.
Then changed oil and filter. Old oil was like new. No water. No gunk . No metal.
All went well. Filled with 20-50. Ran again. Same knock.
Have not run engine for more that 5 minutes total.
Asked old owner , he maintained well and Said nothing abnormal with engine when parked.
I listened with a mechanic scope to the lower engine block on both sides and that seemed normal. It sounded a bit louder when scoped at the valve cover. But really only heard normal valve ‘clicking’ with scope.
I’ve included a few pics of my rig and a video clip with the knock.
Any ideas of the noise before I crack the lid open?
Sound familiar? Stuck lifter?
Does anybody hear anything major?
My first fj40. Cannot wait to drive it, but don’t want to hurt the engine. Being cautious.
Thanks in advance for responding.
PS I cannot post the video?? Any tips on how to post a small ‘.mov’ video to the forum?
JDS

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Pull the valve cover, have a lookaround, and do a valve adjustment.

Welcome to the world of solid lifters.
 
Elder Statesmen,
Thanks for the reply!
That is what a friend told me also.
I am going to pull the cover.
I am working on how to post a video with the sound from my i-phone. Better at oil changes than phones!!
JDS
 
PS I cannot post the video?? Any tips on how to post a small ‘.mov’ video to the forum?

The forum will only accept video from certain sources, not just anywhere. Post your video on YouTube, then when you create (or edit) a post here on Mud, click on the icon in the middle of the row of icons that shows up above the post window, it looks like three dots in a row with a little down arrow next to them. This will pop up an "insert" menu where you can choose "media" at the top of the menu, then it will accept the link from YouTube and then the video will show up when you complete and save your post.
 
Funny how every vehicle "ran well before parked" 🤣

Either way great looking 40. Put a video up and we can listen. I agree, pull the valve cover and have a look since you will want to do the valves anyway.
 
The forum will only accept video from certain sources, not just anywhere. Post your video on YouTube, then when you create (or edit) a post here on Mud, click on the icon in the middle of the row of icons that shows up above the post window, it looks like three dots in a row with a little down arrow next to them. This will pop up an "insert" menu where you can choose "media" at the top of the menu, then it will accept the link from YouTube and then the video will show up when you complete and save your post.
Thank you Chubicabra!
I am a newbie so your help is very much appreciated. Trying utube for the first time too!
JD
 
@JDS

Elder Statesmen,
Thank you Chubacabra!
Some help about the forum tricks/treats since you are.new..
The users name is the line above what you referred to them as, the line you selected is a fill in space about the user... The Elder Statesman is @65swb45 AKA Mark of Mark's Off Road. The Chubacabra is @1911 who is another respected member of the forum. If you type the @ symbol and begin to type their user name a pop up window will appear with matches of user names. When you select the correct one it will alert them that you referred to them. Their name will appear with the @ symbol in front of the users name in red in your post like it does in mine. That way they will know that you referred to them or their post and may reply faster than randomly seeing your thread reappear on page one.
HTH,
Will
 
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@JDS



Some help about the forum tricks/treats since you are.new..
The users name is the line above what you referred to them as, the line you selected is a fill in space about the user... The Elder Statesman is @65swb45 AKA Mark of Mark's Off Road. The Chubicabra is @1911 who is another respected member of the forum. If you type the @ symbol and begin to type their user name a pop up window will appear with matches of user names. When you select the correct one it will alert them that you referred to them. Their name will appear in red in your post like it does in mine. That way they will know that you referred to them or their post and may reply faster than randomly seeing your thread reappear on page one.
HTH,
Will
Will,
Thanks for your informative reply.
I hope I don't make this many mistakes fixing my rig!
JD
 
These are the inexpensive mistakes to make... much better to make those than the expensive ones. That's a nice ride you found by the way, and being a post 79 model we can't give you a hard time about the headlight bezel being upside down since they are rectangular unlike the earlier models.
 
If it’s a loud knock like on a hollow door that gets louder as rpm increases... you likely have a spun connecting rod bearing. Hopefully that’s not what it is. You’d need to have the crank turned, rods machined, and install oversized bearings. And if you’re in that far might as well do the rings and the head.

Or, the route I’d go, pick up a newer good running 2F for $300 and be back on the road in a few days.
 
Don’t discount exhaust leaks either - i had a “knock” in my 283 SBC that ended up being a blown donut at where the manifold met the exhaust. I could have sworn it was a lifter tap by listening to it. A mechanic's stethescope really helps pinpoint where the noise is coming from.
 
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Try removing each spark plug wire in succession while it's running and see one of them makes the noise go away. If so, then pull the oil pan and check the bearings for that cylinder.

Good job on not running it long, and running thick oil. The less time you run it until you figure out what's wrong, the less damage will take place. Be patient, and don't drive it yet (even though the temptation is strong).
 

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