So I took my car out on a long road trip. i was hot roding and racing on the way back. A couple of stretches above 100 mph, maybe 4000 rpm. When I got off the freeway, I could hear the knocking. I went the mile home anyway. This is what it sounds like now. How F'ed am I?
FPRR crate 306 a couple of years in the car. I struggled with the Ford ECU tuning and went with the Holly HP computer about 6 months ago. This is the first time out on a serious drive with the Holly.
Well, does not sound good. Is the FPRR a roller engine? Yes, it is a roller cam 5.0
How does the oil look? On the dip stick it looks new.
Is the sound localized? It is hard to tell.
Next step would be to drain the oil, pull the filter and check for shavings. Cut the filter in half. Then I would pull the pan and have a look. I will have to wait until I am sober. Well, actually, I am sober now, but that is about to change. >
Hopefully some of the gurus will also chime in here.
I blew a head gasket once (supercharged motor) and it sounded just like that. The metal ring along the edge of the cylinder on the gasket had blown into the cylinder (still attached to the gasket though) and the piston was slapping it every time it came to the top.
The chip in the computer was all messed up and was pulling way too much timing...so when I got on the gas too hard, the head gaskets (and other stuff) gave up. In my case, I had other problems with the motor too (cracked a couple of pistons near the rings) and bearing wear, so it was a total rebuild.
Don't fret I'm drunk now too. Sounds deep, lower end. Hard to start sounds bottom end. Hook a separate oil pressure Gauge to it. Run short time only but you sound like bearing. I've had three 5.0 Fox body's pretty bullet proof. You might have trashed your oil pump, and spun a rod/ main. Your definitely gonna have to pull pan. Don't run it any more.
Check the easy stuff first. May be just a loose rocker. Video sounds like it's on the top side of the engine... to me anyway... but what do I know. Well... I got homemade white lightnin' and I got beer. Here's to ya!
A little hard to say due to the sound quality. To me it sounded similar to an exhaust leak on a header tube or something. Besides the noise, how does it run? Any vibration or knocking that can be felt? I just went through something similar on my 66. I recently finished putting in a GT40P. The motor sounded like it wanted to dump the lower end all over the road from inside the car driving down the road. I just found 1 of the Crane roller rockers hitting a baffle. I temporarily added a second set of gaskets to both covers. Still noisy but no where near as bad, sounds like a mechanical cam. I do need to take it out on the road and see. M
A longer clip would be helpful too and give a few different angle of where the noise is coming from.
+1. I've broken the factory stamped pedestal rockers before. You get the nasty rattle along with a skip. If so, pull the pushrod and roll it across a flat surface to make sure it isn't bent, toss a new rocker on and drive it!
OK, this happened to me....
I got into a little spirited acceleration, during which, I missed shift. Almost immediately, I had a solid ticking sound, which was not there previously. Fearing I damaged a lifter, I pulled the intake and inspected the the lifters and valve train components (all roller components). I found nothing unusual, however, after reassembly the ticking was still there. Many of youse guys suggested it could be an exhaust leak.......and it was.
Hopefully, the same for you......
I would guess a rocker arm at this time, maybe from a bent pushrod.
It's hard to tell tho. I had a similar sound before on my old 93 5.0. That turned out to be a check valve from the air pump to the exhaust had broken. Super easy fix on that one.
Like racing yourself with zero traffic, or racing a kid in a Civic. 100 mph with even one car around is asking for trouble, might as well crack open a bottle. 100 mph with zero cars in view may not be wise, but many here have done it.
Like racing yourself with zero traffic, or racing a kid in a Civic. 100 mph with even one car around is asking for trouble, might as well crack open a bottle. 100 mph with zero cars in view may not be wise, but many here have done it.
There are two ways to isolate noise, the first is a long screwdriver placed on the bone of your ear and touch the tip around the motor. You can separate valve tappet noise from lower end noise and localize which is or are the offending tappets. Works for timing chains and waterpump and alternator bearings well.
Second is to use a short garden or heater hose, again one end in your ear and the other probing around the motor. This is very good for exhaust leaks and the old school method for syncing multiple carbs.
Another good tool is a timing light which sets the cadence for the valve train. If the noise is twice as fast its in the lower end.
I just posted this on another engine rattle post. WIth the screwdriver method, I can usually find which journal is the offending one if its in the lower end, can find a dead lifter also. GOod luck
So it sounds like that is no definitive answer, which I expected. It will take more investigation and inspection.
I guess I will start with a compression test while I still have oil in it. That might give me a cylinder and a side to start with. Then I can draining the oil and check the filter. Then move to pulling the valve covers and inspecting the rockers. Then either the intake or oil pan depending.
At least it does not look as bleak as it did last night.
if your oil level was full and you kept clean/fresh oil in the engine it is unlikely a rod bearing in my opinion. Get a stethoscope and start listening. If you neglected the oil changes then it is a good chance of a rod bearing being the issue.
If it was me, I'd start taking it apart from the top. If you don't find the culprit at the top, pull the engine and continue with the disassemble until it shows it's ugly head.
It sure does sound like you spun a rod bearing. Anyway, here is how I would proceed if it was my car:
- First, don't run it all. You can easily destroy the entire engine if you do in fact have a spun rod bearing. If the rod end cap comes off, even at idle, you'll have a connecting rod protruding from the side of the block.
- Remove the headers and inspect the gaskets. It should be obvious if a header gasket blew out. If the gaskets look good...
- Remove the valve covers and inspect the rockers and pushrods. If something is amiss, it should be pretty obvious. If the valve train appears OK...
- Remove the oil pan and inspect the rotating assembly. Again, any problems should be obvious like bearings sitting in the bottom of the pan and a rocker that's loose on the crankshaft.
FYI, in my experience, a spun crank journal doesn't make noise at idle like your engine does. It will sound fine until you rev it up a little. Then the crank starts flexing and it makes a lot of noise. Unfortunately, a spun rod bearing sounds EXACTLY like your engine in your video.
The video is too short but it sounds like a leaking header gasket to me.
I feel sorry for you city folk. Where I live I can sometimes drive for miles without seeing a car on the back roads. Roads are mostly flat and straight too. Still I hardly drive faster than 5 or 10 mph over the speed limit due to all the cops on the road. Sometimes though I open her up for carbon removal.
I'm sure he was running on 99, which is the new, 3rd loop around Houston. Traffic is light and ive run over 100 on it as well. Very low population area and very few ramps. It's out in the boonies
Wow, things must be different on the east coast than here in the Bay Area. I'm 61 and still like to open up a car or bike to way over 100. I've got a friend that's 58, and he races his 67 El Camino every Friday night against not only kids, but guys our age. I don't drive as fast or as often like I used to, but opening up your car makes you feel like your alive, not waiting to be 6 feet under!
Here's how I see it.... on some parts of the Autobahn there is no speed limit whatsoever, and the fatality rate on those sections is less than it is here in the US where the speed limits are 70 and below. Obviously our speed limits are too LOW!
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