hhuuhh?? lower knocking
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hhuuhh?? lower knocking
My 78 has a lower knock at idel it just started. It is not riythmic though -it comes and goes. it instantly quits when RPM's go up and oil pres is cold idel 55psi, hot idel 30-35psi it sounds like it's on the lower end of the motor but no completely sure
Help
Dustin
Help
Dustin
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yeah man mine does the same but dont know whats wrong. it runs fine and is still very strong. how many miles on your engine? ive got an 80. and just put bearings and an oil pump in mine .(13 mounths ago). its got a real quiet knock in it and sounds like the bottom end to me. the piston walls were like perfect so i didnt rering it. and the wrist pins didnt feel like they too much play in them.
please help im stumped
thanks, thecowboy
please help im stumped
thanks, thecowboy
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From: SURREY,BC,CANADA
Dustin I Think You'll Find That Your Main Bearings Are Toast. When The Oil Is Cold It's Thicker And Makes Up For The Wear And The Same For When Off Idle But In That Case It's Because Of The Increased Oil Pressure. In Cowboys Case I'm Thinking The Crank Is Worn And When You Put In The New Bearings You Went With "standard" Size Instead Of Having The Crank Reground And Using An "oversize" Bearing These (if Memory Serves) Start At .010 And Go Up In .010 Increments. Before You Put In The Bearings Did You Remove The Crank And Have It Polished And/or Ground And Mic'd? If Not Maybe You Should Of. Dustin If You Find That I'm Right When You Check Your Bearings That They Are Worn Out Make Sure You Have Your Crank Checked As Well Even If The Crank Turns Out To Be Ok At Least You'll Know For Sure.
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OK ...... it does it cold or hot does n't matter, ME and dad rebilt it about 4,000 miles ago with .010 over bore -remove ridge new rings, cam bearings main bearings cam and rod bearings. oil pump rebiult head, rear seal, gaskets, wrist pins looked good. We did alot I might have left out some stuff.I just put mains bearing in thier "Cleavites" I think 4K ago how can they be toast????
The noise is loudest on the middle of the oil pan under motor mount witha 5/8" hose
I'm kinda sad I 've put so much time and money onto her
thecowboy : Where do you here the noise loudest with a hose up to your ear???
Oh and it CAN"T be heard on the drivers side only the passanger side
The noise is loudest on the middle of the oil pan under motor mount witha 5/8" hose
I'm kinda sad I 've put so much time and money onto her
thecowboy : Where do you here the noise loudest with a hose up to your ear???
Oh and it CAN"T be heard on the drivers side only the passanger side
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alright, aparently my engines been rebuilt before i did it because it did have oversized bearings in it and i replaced them with what i took out. (forgot what size i think .010 over) i did the bearings because it was knoking real bad at acceleration and pulling a load. (defenetly a main bearing ) when i put it all back the knocking was gone. so it cant be a main bearing. i havent checked it with a hose yet but i will tell you when i do. (no i didnt mic the crank, now i wish i did)
thecowboy
thecowboy
