Technical 305 making knocking noise

Sounds like a rocker arm off.

 

Ya ,pop the valve covers.You went for the throttle and i closed my eyes.

 

pull valve covers youll find problem.

 

If you put your right foot all the way to "full wood"
the noise will eventually stop and you can diagnose the failed part easier.
JUST KIDDING

 

LOL My granddaughter hit the key on my 307 the first time we started it and when it made noise she giggled. Two noises within about 10 seconds. That was a good day.

 

Maybe a cracked rocker arm, bet the bottom is pulled out of it.

 

I have run it without the fan belt and noise is still there. I took off valve covers to check for wear (no marks inside valve covers) and didn't notice anything that jumped out at me I will attempt to make vid of this with truck running and oil splashing. Will try to this after work today or by Friday. This is not a sound I can diagnosis too late and still be friends with my neighbors.

 

I don't know maybe I'm too OCD but if it were mine I wouldn't be running it at all for fear of the culprit causing even more damage. I'd drain the oil looking for metal pieces or flakes, pull the pan and inspect rods, bearings, etc. If all is well, pull valve covers and rotate crank over by hand checking rocker movement. Personally, I couldn't run it for a moment until I was 100% sure I found the issue.

 

still say rockers. Listened to video several times and now I'm convinced its some type of morse code.

 

The noise is not happening at a continuous beat. It varies even though the engine is running at steady rpms. Fan water pump is first thing to check as suggested

 

As mentioned earlier..........pull the valve covers and you will find the problem.

 

Unhook the battery ,remove the plugs and spin the crank by hand and listen.also check the windage tray in the oil pan,sounds like tin gettin smacked around .

 

Possibly spring on fuel pump arm broken? Lippy

 

35 lbs at idle is too much.
This isn't the cause of the noise, but a symptom of a larger problem.

 

Another thing to check is the motor mounts. Had a friend that bought a nice chevell cheap becaus of a rod knock. used a pry batr to lift the engine a little and the sound went away.

 

I think "woodhawg" is on to something, the sound is not constant, it changes. In the video it looks like you went for the throttle, I could not tell if you speeded it up or not but what happens if you do?

 

Just so you know, I'm not tring to get you to damage the motor. go easy, just see if the noise changes. Just sounds like something loose or cracked.

 

I sped up the motor to about 2000 rpms.

 

and what happened? in the video it sounded like the noise went away, could not tell

 

Wow. after listening to this a couple more times it brings back memories of a loose convertor nut & bolt

 

Try listening to it with a piece of dowel or old broom stick, just a 2' piece is all you need. Put one end up to your ear and the other where the sound is and narrow it down.

 

It did go away for a couple seconds them come back.

 

I will try to take a vid under the car as well.

 

I have had that noise on a sbc turn out to be a pushrod stuck THROUGH the rocker arm.Not even that unusual.Easy to check for too.

 

That's the first thing I thought of. If you have a bolt that backed out it could be smacking something around. I'd take a quick gander under there and see if there is anything loose.

I know a few people have mentioned a loose rocker arm or stud, and I'd second that as well. I had a SBC that had a loose exhaust rocker and it sounded like the engine was going to come apart. Just taking a quick look inside isn't good enough. You need to check the lash. I readjusted mine and put better locking nuts on and it was a non-issue after that.

 

Just a thought here. I had a similar noise in my roadster when it had a 350 turbo in it. It turned out to be the flywheel cover hitting the flywheel. Just a little tweak and it was gone.

 

The 305 in my 49 Ford was making the same sort of noise.

Pulled the valve covers and one rocker had slipped off a pushrod.

The pushrod was bent, replaced, adjusted valves, all is good.

 

I don't know but I bet it is something like flex plate. keep looking in that area. if it was rod or lifter, I would think it would not be so uneven...

 

Are you saying that you recently uninstalled the mechanical fuel pump? If so, what did you do with the fuel pump push-rod before you bolted on the block off plate? Did you leave it in or remove it?

 

Your problem is a pushrod, rocker, or rocker stud. Get to compression tdc on #1 check intake 1,2,5,7. Exhaust 1,3,4,8. Rotate crank 360 deg. Check intake 3,4,6,8. Exhaust 2,5,6,7. You will find the loose stuff.