390 tapping BACK!!!!
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From: Tillamook
390 tapping BACK!!!!
Okay, I posted a thread here about 3 weeks ago about a top end tapping that I couldn't track down. Well after 1 month, new waterpump, switch to an electric fuel pump, new lifters and a new cam, the top end tapping is STILL THERE!!! #8 lobe on the cam was flat and the lifter was pretty beat up so I thought that was the prob but.....NO! Can't hear the tapping under accelleration but very eveident as the motor idles down through 3000 to about 2000 RPM. It's a slack noise, just with maintenance throttle and deceleration. One of the push rods was bent pretty good. When we had the left head off, we took a good look at the pistons and they looked great. We bore scoped the right bank and all looked good. Oil pressure is a constant 60. Spun the oil pump with a drill and no noise and good pressure, constant. I'm really pulling what hair I have left, out on this one. Anyone have a clue or a similiar experience on this one? HELP!!!!
Thanks, Bob in Tillamook, Oregon
Thanks, Bob in Tillamook, Oregon
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From: Sun River St. George
390 tapping BACK!!!!
I am glad you got the camshaft and lifter business sorted out. That could have caused serious engine damage. Fe's are famous for tapping wrist pins. Try this, hook a timing light to any plug wire, run the engine and listen, if the light flashes in time with the noise it is valve train related if it knocks twice for every flash it is engine related (wrist pin). Next trick is find which cylinder is knocking and disable the spark to it. If the noise stops or changes significantly it is wrist pin or rod bearing. Wrist pin noise while annoying can be deferred until next overhaul.
William in Atlanta
William in Atlanta
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From: Tillamook
390 tapping BACK!!!!
Hey William- I'm sure you know how hard it is to "pin-point" a noise location but we have a pretty good consensus that the noise seems to be coming from #4 or 5. We pulled both and did'nt find any slop but that's not saying that we could have somewhere else. We are going to try your suggestion, sounds very reasonable. At the very least maybe we can narrow down the search. One guy on the forum said that he had a similiar tapping in his FE for 80k+ and nothing ever came of it! I don't know about you but I couldn't deal with that, I want the truck fixed. I know quite a few of the guys here are going to cringe when I say this but I drive my truck pretty infrequently and short miles at that, mostly to and from work. So there is most likely gonna be some condesation build-up in the block between use. I think that's the culprit which led to the demise of the cam. Also another tidbit, the noise started about a month before I tore into it, very soft, quiet but it got progressively worse quickly. I only drove it 4-5 times since the onset of the noise and then only 5-20 mile trips. Sorry bout the long post but the more info, the better chance I can get some remedy.
Thanks, Bob in Tillamook, Oregon
Thanks, Bob in Tillamook, Oregon
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From: Balfour
390 tapping BACK!!!!
I have a 360 2v thats been ticking for 10 000plus miles,
16.2seconds @91mph, best way to deal with these
noises is get a good stereo, or some loud exhust
unless it affects performance...
16.2seconds @91mph, best way to deal with these
noises is get a good stereo, or some loud exhust
unless it affects performance...
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