The video/audio quality is not the greatest, but that sounds like rod knock to me. Hopefully i'm wrong.
351w-guess that noise
So last night I took the Mustang out. At about 6,000 rpm suddenly the engine stutters and there is a loud ticking noise. I get off of it, pull over, and shut it down. I start it back up and go under the hood to see if I can determine where its coming from. Can't really tell so I tow it home and now I'm trying to determine my plan of action.
I've drained the oil to look for any heavy metal deposits..I didn't see any.
I think my next step is to get a scope and start examining the rockers to see if one has came loose or look for any other signs of damage.
Its a 351w, trickflow twisted wedge heads, howards cam with their hydraulic roller, link bar lifters.
Here is the video shortly after shutting it down.
https://youtu.be/YVIgIwhRepg
What's your guys' opinions?
I've drained the oil to look for any heavy metal deposits..I didn't see any.
I think my next step is to get a scope and start examining the rockers to see if one has came loose or look for any other signs of damage.
Its a 351w, trickflow twisted wedge heads, howards cam with their hydraulic roller, link bar lifters.
Here is the video shortly after shutting it down.
https://youtu.be/YVIgIwhRepg
What's your guys' opinions?
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I also hope you are wrong lol. Whats the easiest way to determine rod knock? Remove the oil pan and look for discoloration or a loose rod?The video/audio quality is not the greatest, but that sounds like rod knock to me. Hopefully i'm wrong.
Yeah with the oil pan off you will probably be able to find one of the rods is a loose on the crank. But I would start with the simple stuff on the top side by looking at the valve train first. That would be a lot easier to fix. Hoping for a simple and inexpensive outcome!
Remove the valve covers first. Look for loose rockers, bent pushrods or other such tragedies. If you don't find anything after a thorough inspection up top, then move to the bottom of the engine.
Agree on looking at the valve train first and see if any rockers are loose or pushod slop.
You could also cut the oil filter open look in each pleat and see if there is anything in there that should not be. Depending upon what it is (metal type), that may give a general idea.
As a general practice, when I do an oil change I always cut the filter to inspect.
You could also cut the oil filter open look in each pleat and see if there is anything in there that should not be. Depending upon what it is (metal type), that may give a general idea.
As a general practice, when I do an oil change I always cut the filter to inspect.
Thanks for the input everyone! I'll start with the valve train and work my way down since it might all have to come apart anyways.
If it's not suddenly running rough you can probably skip the valve-train check. Sound quality isn't great in videos but I'd check the fuel pump first. If you raise the engine speed slightly and then suddenly close the throttle and the noise momentarily goes away, then I'd pull the pan and check the rod bearings and, if they are okay, look for a bad wrist pin or broken piston skirt.
Could you explain why I would check the fuel pump? Very curious what on the fuel pump would cause this.If it's not suddenly running rough you can probably skip the valve-train check. Sound quality isn't great in videos but I'd check the fuel pump first. If you raise the engine speed slightly and then suddenly close the throttle and the noise momentarily goes away, then I'd pull the pan and check the rod bearings and, if they are okay, look for a bad wrist pin or broken piston skirt.
exhaust leak?
The actuating lever on the fuel pump is spring loaded so that after it is moved by the eccentric on the front of the cam sprocket it returns to an "at rest" position. If the spring loses tension, breaks or there is some other issue preventing the lever from returning it will smack against the eccentric and make a tapping noise like a collapsed lifter.Could you explain why I would check the fuel pump? Very curious what on the fuel pump would cause this.
Definitely not an exhaust leak. After I shut it down, there was very random, loud knocking/ticking noises coming from the engine. It will also not stay idling any longer which makes me think it is more valve train related. I could be wrong though.exhaust leak?
If it's making noise AFTER the engine stops rotating then it's most likely HEAT related...Definitely not an exhaust leak. After I shut it down, there was very random, loud knocking/ticking noises coming from the engine. It will also not stay idling any longer which makes me think it is more valve train related. I could be wrong though.
When I say shut it down, I meant after the 6,000 rpm run. I turned off the engine, came to a stop, and restarted the engine. With the engine idling is where it started making the random knocking/ticking. Sorry for the confusion.If it's making noise AFTER the engine stops rotating then it's most likely HEAT related...
Here is a video related to the #12 comment:
Valvetrain, exhaust leak, or mechanical fuel pump is more of a ticking noise. That doesn't sound like ticking to me.
Sounds like the exhaust header leak to me or that is one source of noise. There is something in the engine too like maybe valve lash needs to be adjusted or you have a rocker stud got pulled or something but its hard to separate that out with the header.
I’m going to guess a hydraulic roller came apart and that’s the noise you’re hearing. Whatever it is, kudos on getting it towed home. I can never understand how people limp home with some sort of noise to save the price of a tow but cost themselves an engine.
I do hear more than one noise in the video. It sounds more like a rod knock than it does valve train to me, but I'd definitely be suspecting the mechanical fuel pump and check it first since its easy to do.
Did oil pressure drop while driving? What does the oil look like, anything metallic looking on the stick?
If there is noise after shutting down and not running then I'd agree on it being heat related? Did the temp gauge spike before this happened?
Did oil pressure drop while driving? What does the oil look like, anything metallic looking on the stick?
If there is noise after shutting down and not running then I'd agree on it being heat related? Did the temp gauge spike before this happened?
1 - 20 of 58 Posts
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