Guess the knocking noise

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BWDart

BWDart

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I will be pulling the 318 this weekend, any guesses on what is knocking?
[ame="http://www.youtube.com/watch?v=qjIHMbgTMuU"]YouTube- Motor Noise[/ame]
 
What knocking?Has it got "any" oil in it? Wow ,that sounds ugly.I suppose it could be a lot of things.8)
 
Wrist Pin?? Maybe bent pushrod. Doesn't sound like a rod knock it's not that deep muffled sound. How is the oil pressure??
 
Mileage on it ??? and whats the oil pressure like? Timing chain slapping the case?? One more thought, a bad roller lifter..
 
The 360 is ready and waiting to go in along with an a-500 OD trans and 8 3/4 rear.
The oil press is good just thought I'd test some ears before it comes out.
 
61 miles from home cruising down the 405 in the left lane at a lazy 3500 rpm in traffic I heard some big clanging in the motor. I pulled off immediately. After some tests at home… 99% sure the number 6 rod bearing is toast.

I did a ring and bearing job on this never bored, OE 1968 piston, numbers matching 340 motor in 1994 just after I got the car. The odometer said 45K miles on it then. I’ll assume that was 145K miles. Well, it’s 210,000 miles now. It’s been a long journey with this motor. It’s served its duty above and beyond what can be expected… So long my friend.

The You Tube videos of the engine idling when we spark tested all the cylinders....Sure enough #6 made a HUGE sound difference. Textbook rod knock stuff. Has a deeper tone to it like a bearing. Put a good oil pressure guage on it and it has no fluctuation.

You can hear and see it here:

[ame="http://www.youtube.com/watch?v=gdAm4_RvueI"]YouTube- PICT2702.MOV[/ame]

[ame="http://www.youtube.com/watch?v=DbT2wgT4puA"]YouTube- 340 rod bearing[/ame]

I allready have a 340 STD bore I bought at Spring Fling preparing for this. It's stroker time!! :toothy10:
 
Is it a factory roller engine?? I tore down a magnum roller engine awhile back and it had like 6 trashed cam lobes... I say cam and or lifters....
 
Sure sounds like a piston smacking a valve. Don't think it's wrist pin or rod/crank bearings, to rhythmatic for a piston coming apart.
 
It's a pre magnum, factory roller, all the rockers are tight when turning it over with the starter, it all started after a block long tire smoking, started missing then smoothed out and started making the noise.
 

Make a video for us!!!! Take a brick and put it on the gas pedal and we will take bets on how long it will last! :cheers::snakeman:
 
funny...after I did a long *** burn out, my 318 made some sort of...grinding noise...lol...now look i have i fully torn apart! lol
 
demon seed said:
Sure sounds like a piston smacking a valve. Don't think it's wrist pin or rod/crank bearings, to rhythmatic for a piston coming apart.
Click to expand...

If a piston is slapping a valve it seems like either the piston would bust or the valve would drop into the cylinder, wouldn't it ??? Sounds like a constant rythem of more parts then one....
 
If the oil pressure is good at a hot idle and there isn't any slack in the rockers/pushrods, I'd put my money on wrist pins. If that video was taken at idle, there's more than one.
 
BWDart said:
It's a roller motor all lifters are working and no bent push rods.
Click to expand...
How do you know? Did you run the motor without the valve covers? If the engine is running fine then it could be a roller rocker hitting the baffle on the underside of the valve cover. Especially if the rocker assembly was installed without shims. Maybe one of them loosened up and shifted left or right.
 
The valve cover is smashed in, thats the rocker arm hitting the cover!!!!!!!!!!!!!!!!
 
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