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[font size="1" color="#FF0000"]LAST EDITED ON 12-Nov-00 AT 07:06 PM (EST)[/font][p]well, at least I think it is the valves. I was wondering if anyone out there has experienced similar noises (very loud tapping and just a lot of racket fom the top end of the engine)(not a low clunk like a bearing)under load, particularly in the lower end of the rpm range. I think I remember someone telling me that it was "normal strait six wear". I assume the noise can be attributed to wearing parts (lifters, valves, rocker arms, etc.). Perhaps the tollerances are increasing with wear, but I am not sure. Are the valves on this engine adjustable to take up the excess tollerance? Any help is appreciated
Captain Tim Bland
'86 F150 LWB 2WD
300 I6 1bbl
3.08 Geared 9"
three speed w/od
My 240 made the same noise, I removed the valve cover and adjusted the lifters. No more noise. If you take it off, the lofters are right there. Start the engine and if you rab the lifters one by one, you can find the one that is making noise. Take a socket and tighten it till it stops making noise. Then turn it a 3/4 turn. If you want to adjust all the lifters by loosening them till they rattle ans then repeat what I just told you. Good Luck.
[font size="1" color="#FF0000"]LAST EDITED ON 16-Nov-00 AT 00:10 AM (EST)[/font][p]Here are some Tecniques that might help. Listen to the Valve end of the rocker arems with a hard rubber hose. Old Garden hose.
When you adjust the valves, use a vacuam guage.
With the Guage in place, if you get any bouncing, you have a very tight or very loose valve. Burned possibly. Try to locate that one before you get started on the rest of them.
You can tighten a valve, 1/4 turn at a time, watching the guage. When the Guage starts to bounce you have it too tight.
Back it off 1/4 to 1/2 a turn.
I hope your noise is not from bad oil circulation such as a worn cam bearing. Always do a Compression check, on a Warm engine, to see if you have any suspect cylinders.
Speed aint all that important, there were Snails on board the Ark, along with the Cheetas!
Is this noise when you you accelerate or all the time? It may just be pinging. Try a higher octane gas. How many miles on this truck? The replies on adjusting the valves seem to be right on so if nothin else works try that. NOTE... excessive pinging may and will cause piston damage.
It's not pinging, I am pretty sure of that...I had a pinging problem last year, but I swiched to 89 octane and fixed some vacuum leaks that were causing the engine to run lean. the noises are only under heavy load, low in the rpm range (between 1000 and 1500) Not sitting at idle (like piston slap) or a low bearing clunk. It also dones NOT do it under any load above about 1500 rpm. Other than valve adjustment, is it possible that timing could be suspect? in addition, the accelerator pump on the carburator has been functioning intermitentaly since last summer (I have ordered a replacement carb)...could this be partly to blame? i know that a poorly tuned carb can cause engine noise. I don't think it is a bad cam bearing, but just to be safe i will do a compression test tomorrow.
thanks,
Captain Tim Bland
1986 F150 2WD LWB
300 I6 1bbl
3.08 geared 9"
three speed w/od
I wouldnt think the carb would have anything to do with valve rattle or such... Does it tap at an idle? How about when you accelerate it in N? If no to these, I'd be lookin at a possible wrist pin problem OR check very closely for an exhaust leak at the exhaust manifold/head area. Had an exhaust leak there once that sounded like a piston was about to come out any second! Good luck and keep us posted!
My valves (rocker arms) are noisy as well. I just bought a 1980 Ranger, I-6 that shows 107K on the odometer. It runs well except for the clacking noise when I accelerate (even easy) but only after the engine is warm. Ther 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 throtle solenoid disconnected and colapsed. 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 espeacially 4th. I cant go over 60 mph without the clacking noise. Who can answer this one? Again I must empasize that when the engine is cold there is no noise. Thank you for listening.
I have the same problem with my 1993. I only hear it when under loads (such as accelerating in O.D. before it kicks down, or climbing hills). The engine only has 25K on it since being replaced with a Factory longlock, and I never had the noise with my old engine (tho the 3 main bearings it spun made one heck of a clunk!!!).