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rebuilt 318 knock noise around 2500

Alright everyone, Its been a little while but i said i would come back and report my findings. We wound up removing engine to investigate all the way. I had everything to rebuild it anyway. This is the 3rd rebuild on this motor. That just seems to be my luck but thats ok. I always make it a point to learn from my mistakes or just learn new things in general. So don't roast me too bad but here we go... When the motor was first done by the machine shop naturally the crank was turned 10/10. When we had the engine on the stand flipped upside down every single rod was loose. Turns out even tho my reciept for the rod bearings said .10 they were standard size bearings! Number 4 and Number 7 were spun so that had to have been my noise or just all of them were probably making noise. No noise at idle tho. Main bearings were .10 and the crank turned very nicely. It really is something that for 8 years my motor lived this way and as hard as i have been on it. I knew that 20 psi Oil pressure was not right. I Mic'd the crank journals and recorded every measurement. Thankfully the crank was not out of round and i gave it a lil hand polish per the "How to hot rod a MOpar" book and it worked out. New main bearings, New rod bearings, New cam bearings, Cleaned the pistons and rings, Thoroughly cleaned the entire block and the oil holes in the crank and thru out the motor. New rear cam plug, and new lifter galley from plugs. All new gaskets, Epoxy primered the whole block, then Chrysler Orange with some 2K clear on top, New Lunati Voodoo flat tappet 494/513 268/279 cam and lifters, Reassembled primed oil and gas, fired the bitch up broke it in for 20 minutes. The motor sounds healthy and makes 80 psi cold start and 40 hot idle. I appreciate all you that commented and gave me some tips and pointers and things to look for. The motor is virtually leak free other than what seems to been a rear main, or possibly the cam plug... unfortunately but that is small stuff that can addressed and handled. I have the felpro rubber seal not the rope seal , which ive read if the crank had the grooves or slits where the rear main seal goes it might be best to use the Rope style seal. Other than that, this motor is happy, it definitely responds to the extra lift of the cam. 40 psi at idle is a lot more comforting , for me anyway. Anyways Thank you all ! I appreciate you! I will come back with some photos and videos of the build soon!
 
It's awesome you found the issue... and guys not checking bearings happens.... even the all time greatest mopar builder did it (uncle Tony) and it made it to a dyno like that.. Great outcome though for you :)
 
Turns out even tho my reciept for the rod bearings said .10 they were standard size bearings! Number 4 and Number 7 were spun so that had to have been my noise or just all of them were probably making noise.
Wow that's some bullchit work right there. Any builder worth his salt will give you a list of all your clearances because they should actually be measuring them....I guess you know not to use that shop again!
Oh well, glad you found the problem and thanks for following up:thumbsup:
 
Plastigage to the rescue! ( bit late tho)
 


Here are a couple shorts one of cam break in and the other after it was broke in. this motor definitely Like the Lunati voodoo cam 494/513 lift. Its so weird to not hear that knocking noise anymore! Cheers everyone and thank you for your help!
 
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