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Discussion Starter #1
Okay guys... i turn her on (nothing funny!! :D) and unfortunately i can hear a knock coming from the passenger side engine bay... upon further inspection it sounds like it is coming from valve #4. Can i do any tests to find out exactly what is wrong?? This is a 351W and i heard the knock a few months ago and it just went away!! but it is really quite loud right now??
There is smoke coming from under the valve cover on that side but it doesn't smell like exhaust fumes i think it is burning/evaporating oil.... i had another look at her with the valve covers off and she spat all over the engine bay.... how much oil should there be covering the valves and the top of the heads??? I told you i was a beginner mechanic!! :D Anyway thanks for the tips yesterday but how wierd is this i checked everything you told me and still nothing i looked under the distributer cap and and gave it a clean.... and re-adjusted the gap between my ignitor and hey presto!! Starts like a champ!! :D
Anyway back to this problem!! What is it??? valve job?? or what help!! Also i have done the shake test on the rockers... and the one rocker over number 4 i can shake like 2mm to the side and back i can't with the others... i tried to tighten it but boy are they on tight!! Is that one just worn?? Another thing could it be timing?? Maybe my timing chain is worn and it keeps losing it?? hmmmmm.. :1zhelp: :D Do i sound desperate!! Your right!! I am !! Anyway thanks for the help as always!! This Cat would be in pieces if it wasn't for you guys!!

Thanks again

Stu - :D
 

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Pull the plug wire for that cylinder and see if it goes away. If it does, it might be a rod knock(not good!) If it stays the same, it may just be a stuck lifter....

Bruce
 

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Discussion Starter #4
Tested!!

Okay i pulled #4 and it was the same!! so i replaced #4 and pulled #3 and the knock was gone... well there may have been a very slight knock but i'm not sure!! Shall we say it is 98% better with #3 pulled!! So what does this mean?? Thanks once again!!
Really appreciate it!!

Stu - :D
 

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Kitty... is it a knock or just loud ticking? co # 3 and #4 wires touch each other? also are the plugs in tight?

Redcat as ticking on the right side and it was a loose plug....


Don
 

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Discussion Starter #6
Thanks!!

I'm at work right now so i'll have to check it out when i get home!! but i'm sure that it's a Knock rather than a tick.... but let me double check!!
Thanks for the advice

Stu - :D
 

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Discussion Starter #7
Still Smokin' and Knockin'

Okay she is still doing it.... as i said previous it is a definate knock that goes away when I pull plug #3. What does this mean??? Could bad plugs do this?? (Stu crosses his fingers!! :p: ) or does it mean a valve job??? If so what are your suggestions..... what to do , where to go and such?? How much will it cost?? Also what plugs should a 351W have at the moment they are Autolite 25 is this right??? :1zhelp: Anyway thanks for all the past info!!
Many Thanks

Stu - :D
 

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It sounds like your #3 rod bearring is toast. Which means, you get to rebuild your engine... BUT, before you panic remember, this is only a long distance guess. Try to find a mech you trust( yeh i know, no such thing) or perhaps you could impose on someone from this forum near you for advice. Don't trash the motor without someone knowledgeable looking at it first... Let us know how you make out...
Good luck and I hope I'm wrong...

Bruce
 

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Discussion Starter #9
Can anyone help me out??

Hi!! :D Well can anyone give me some more hints, tips about finding out exactly what is going on with my engine?? Ray, senior motorheads, anyone, if not then i need some help from someone who knows there 351W engines down here in Southern Cali so they can come and have a look at her. (I live in North County San Diego) I am quite [email protected] right now!! WHY ME!!! :p: Ha Ha!! Anyway ideas or suggestions are greatly appreciated! If it was the #3 rod bearing then would that just mean a valve job (if so how much.. guestimate) or a complete engine overhaul??
HELP!!!

Stu - :D
 

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Have you double and triple checked that the plug wires are on the right plugs?
 

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Discussion Starter #11
The final Countdown!!

Here are the final results..... There is a knock or a tapping noise that i have at idle and all the way throught the rpm range. It gets louder and faster as the engine rpm's gets higher. I have replaced the plugs (slight carbon fouling)... and the plug wires as they were showing their age. All plugs are in tight and the wires are properly insulated and not touching each other. They are arranged in the 351W firing order anti clockwise from #1 on the dist cap. If i pull plug #3 the noise stops and the engine sounds fine. I asked a local machine shop about the problem (he didn't hear the engine himself just from my desciptions) and he said i need a engine rebuild. He said it would cost $1400. Firstly with all the symptoms does this warrant a full engine rebuild or just a valve job?? Secondly is this a good price for the work or not?? Any comments or suggestions are welcome.... I really appreciate all the help this forum has given me concerning this problem and others.
Many Thanks

Stu - :D
 

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well, a valve job will not fix the knock. If its the bearing, it means #3 connectiong rod is loose in its bore and knocking when there's spark on it. It will still make noise but not much when there's no compression (spark) to it. So when the wire is back on, it is under load. So, rebuild is nececelery.

Rick
 

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Discussion Starter #13
Update!!

Hi everyone..... well to say i am confused is an understatement!!
The smoking is oil leaking onto the headers from a bad valve cover gasket. So thats no problem..... but...... the knocking has gone??? Yes gone... not a sound.... it's almost as if the mechanic fairy came in the middle of the night and rebuilt my engine!! :p: So what do you make of that?? What could it have been?? I am worried..... :rolleyes: i can't have a problem one day then all of a sudden gone!! I haven't touched the engine what so ever i have been driving her a little but with #3 spark plug disconnected! I just put it back on to hear her on all 8 again and gone.....
All ideas, suggestions are much appreciated!!
Many Thanks
 

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been my experience cars dont heal themselves. you probably fouled #3 plug by driving with it disconected.which means it is still not firing. pull it out clean and install and the knock i bet comes back.
 

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Discussion Starter #15
More help needed.

Hi everyone!! :wave:
Okay i pulled the plug and (it wasn't fouled??) cleaned it a little and checked the gap with a feeler but it was fine!! Anyway put it back in and fired her up... still the same, no noise!! I put in a brand new plug to make sure and still nothing... please help!!! Not that i want to hear that noise again but like cougarguy said cars don't heal themselves!! I am really puzzled like always!!:p: I checked the distributer, plug wires, i even switched that plug wire with a spare one and still the same!! HELP!! :1zhelp:

Also i have another question i can hear strange noises coming from the fuel tank when the car is running?? Almost like something is jumping up inside the tank and hitting the bottom over and over again... it only stops when i kill the engine!! It is definately coming from the gas tank.. I can even feel the vibrations if i put my hand on the bottom of the tank!!
Any ideas?? Thanks for all the help!!
I need a beer!! :beer: Cheers!!
 

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you sure they dont heal themselves? when i first got my 69 and took it on the freeway for the first time, i got home and i heard alot of valve clacking. scared me pretty bad. after that time i never ever heard it again. and that was like 3 1/2 years ago. sometimes they do weird stuff. my moms car even.. 96 Stang... heater blower didnt work for like 2 weeks. then it worked again. been fine ever since. that was about 3 years ago too... i think they do fix themselves sometimes lol.
 

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kitty,
Try putting an oil pressure gauge on the car. You may have some weird oil pressure problem or an oil pump trying to die on you...
 

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Could have soom kind of "carbon" knock and now it's cleaned up enough to be quiet...got me, sorry..........The gas tank sounds it's not venting properly, your profile says "cal" so you have a closed system and I'm afraid I'm not that up on those. But someone here should be....Good luck..

Bruce
 

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I had a 78 Bronco with a 351 W in it.Every once and a while I would get a ticking noise on the Pass side.I think if I remember it was a sticky lifter.It did it mostly on a cold start.But went away
 
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