noisy valves
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Joined: Dec 2000
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noisy valves
My valves (rocker arms) are noisy. I just bought a 1980 Ranger, I-6 that shows 107K/207K? on the odometer. It runs well except for the clacking noise when I accelerate (even easy) but only after the engine is warm. There is absolutely no tapping sound at idle. Oil pressure is good, according to the dashboard gage. I flushed with Gunk engine flush. I have replaced lifters and springs. The rocker nuts would not quite turn one full turn,in most cases, after the push rod was seated on the lifter before the nut would bottom out on the stud. Also set timing at 6 BTC @500RPM with vacuum disconnected and plugged and the throttle solenoid disconnected and collapsed. Timing seems to be advancing fine. Changed spark plugs. Vacuum gage reads over 20 and steady. I've tried higher octane gas. The noise actually doesn't occur until I shift into 3rd and especially 4th. I cant go over 60 mph without the clacking noise. Who can answer this one? Again I must emphasize that when the engine is cold there is no noise. Thank you for listening.
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Joined: Mar 2000
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noisy valves
the word clacking kind of reminds me of knocking and the you said it did it during acceleration, it sounds like a rod to me, i dont know, id have to hear it. my six made a strange diesel engine noise at idle, as i increase rpms it turned into a tick.
im replacing my rockers, because thats what it has to be on mine ive replaced everything else in the valvetrain, try replacing your rockers and see what happens, if its not that, youve got a bottom end problem.
John Floyd
South Mills,NC
'86 F150 2wd 300 6
Crane Cam 260/272
stock manifolds, w/ staight pipe
im replacing my rockers, because thats what it has to be on mine ive replaced everything else in the valvetrain, try replacing your rockers and see what happens, if its not that, youve got a bottom end problem.
John Floyd
South Mills,NC
'86 F150 2wd 300 6
Crane Cam 260/272
stock manifolds, w/ staight pipe
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noisy valves
It makes sense John to replace rockers next. Before I spent the money though I wanted to do some more checking. Just for kicks I retarded the timing ( a lot) and drove it. All was quiet and it seemed to run well execpt it wouldn't shut off, just kept dieseling. I had to open the throtle plate to keep it running. I wanted to leave it that way but didn't like the dieseling (at 700 RPM idle) when I shut it off. The vacuum showed a steady 12 or 13 indicating the late timing. I guess I just wanted to see if I could get the noise to go away. With that in mind can we be a little more sure there is excessive clearance in the valve train now and maybe rockers will take it up? Why though, did the noise go away at the retarded timing setting? Is it because the valve train is under less load becuase the spark comes after TDC? Thanks
1980
300-6
F150 Ranger
1980
300-6
F150 Ranger
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