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.

 

 

>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.

almost sounds to me like your cam lobes are worn down. Cams aren't too tough to replace. Don't think you would have to remove the engine, probably just the radiator to make room to slip in a new cam. I talked to a mechanic once about it, and he said he hardly ever replaced cam bearings, they just don't seem to wear out.

BTW.. I didn't know that Rangers had an I6, thought they either had a I4 or a V6. Or maybe I am missunderstanding your message.
How many cubic inches or liters is it ?



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.


LeRoy Wolff, original owner of
1984 Ford F150
300 six 3 speed with overdrive
optional dual rusted out fenders
truck's nick name "Old Red"

 

Leroy,
It is an early Ranger, full size F-150 with the 300cu. in. in-line 6. From what I read in the book it's quite an effort to replace those camshaft bearings so it would be nice if I could just replace the camshaft and be done with it. I can't figure out why the engine needs to be fully warm before I hear the rocker chatter? Whatever, a new cam and rocker arms might do the trick. I stated in another posting that when I retard the timing (a lot) the valve noise goes away, but the truck won't shut off because it diesels. Thats because the carb throttle plate has to be opened up at the retarded timing setting so the engine will idle. But why does the noise go away at the retarded timing setting. Thanks

Stuart
1980 F-150 Ranger 300/6