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Fucking Zen as Shit
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16,161 Posts
Discussion Starter · #1 ·
:teehee::teehee::teehee::teehee::teehee:

So back in september my YJ's 360 developed a rod knock. (or piston slap)
To counter i replaced the standard 10w30 oil with 4 quarts of straight 50weight oil and 1 quart of Lucas.
Was a little noisy (rod knock) when first fired it up, but after 2 minutes was silent again, and bonus 60psi oil pressure at idle :rock:


So my question, if dumping the thicker oil in made the rod knock go away is it most likely bad bearings? to where i may be lucky and just drop the pan and replace the rod bearings?

I know eventually the motor will go bye-bye, but this motor is really only a temp anyway until i build the 401 sitting on the floor
 

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I only wheel a boat.
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17,274 Posts
The Lucas fixed the problem. Keep driving it.:teehee:
 

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Fucking Zen as Shit
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16,161 Posts
Discussion Starter · #4 ·
You should be able to pull the pan and throw some new bearings in. I would plasti gage all the clearance's just for shits and giggles but it will most likly be scary. I have seen it done before. Just be ready for a motor swap when it does deciede to go.


yeah, not even going to waste the time with the plasti-gage, i'm sure it is scary. i have a set of rod bearings sitting here too. now it just needs to be warm enough out to do it.

or i need to get off my ass and build the 401 lol
 

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In Da Faaaaaace!!!
1988 YJ
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5,939 Posts
I just wouldn't plan on taking it out wheeling.


all of my connecting rod bearings were like this:


plus my mains were just as bad

mad my engine knock reallly bad.
 

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I am the law.
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29,823 Posts
20w50 and Lucas is what has been keeping the Suburban alive for almost a year. Knocks for about 10 seconds or less at startup if its been sitting for a couple days and that's it. In warm weather, I usually don't hear much of anything at startup.

The amount of oil it eats and burns is a different problem. :teehee:
 

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4,465 Posts
Maybe I should swap oil in mine too. When it is warm and sitting at an idle, wow. Bad noise. Does it while cranking now too. But then goes away until warmed.
 
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