God, when will the knocking quit?
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Freshman User
Joined: Apr 2005
Posts: 39
Likes: 0
From: NW Indiana
God, when will the knocking quit?
I know one of the senior users and/or one of the mechanics must have the answer to this question. The knocking is literally driving me mad! Checked all of the obvious. Deeper sounding than a lifter, but slower. Barely audible when idling, but gets louder and increases in frequency as the RPM's go up. Really loud under normal driving load (acceleration). Seems to be coming from the 3 or 4th cyclinder, behind distributor and the pushrod cover....About where the lifter would rest o the cam. I have so much money into this truck and now I don't know whether to abandon it or to continue on.....new carb, intake and exhaust manf, cap, rotor, water and fuel pump, head with new valves, springs and retainers, rockers, pushrods, lifters, oil pump, radiator, alt, battery, all new gaskets, trans, hubs and list list goes way on....I just don't understand it. Compression and oil pressure are good. Runs great. Just the damn knocking......PLEASE HELP.
Senior User
Joined: Dec 2006
Posts: 145
Likes: 0
IF the bearings are gone, it already went bad, stop now before you destroy the crank. If the pistons(s) are broken, be nice and hop you don't slug one in the hole... my former truck(GM) did this with a 327... not pretty, smoke, knocking, oil everywhere, more smoke. Pull the pan and see.
Elder User
Joined: Apr 2004
Posts: 970
Likes: 3
Wrist piston pins are audable at idle as a double knock similar in sound to a valve lifter. Loose rod bearings are heard on decelleration of the engine and can be made to make the sound by running the engine up and slightly backing down the it down rather quickly. By shorting out the plugs the offending cylinder will stop knocking. Lastly main bearings knock when the engine is straining under load and stop when the load levels out. Sometimes loose torque converter bolts can be mistaken for bearing noise. Hope this helps.
kotzy
kotzy
New User
Joined: Dec 2006
Posts: 23
Likes: 0
i had a similar problem with a 84 f150. ran fine but knocked and got louder with more rpms. i stopped driving the truck and was told that my flywheel might be cracked to check. never did and got a new truck. then igave the truck to my brother and law. it switched hands a few more times among a few friends. was never really driven, about a year later it finally blew up . believe it or not the camshaft broke and took a few chunks out of the block. not bad though the truck had 350,000 miles on it.
just my 2 cents
just my 2 cents
