Pre-go kart checks and a tapping sound

[FDLWproject]

I'm getting ready for my first go-kart and have a few items remaining before its got the green light.

I have the following setup
- 351 W (427) from Forte
- Pro Flow 4 EFI
- Aeromotive 13129 fuel regulator
- Holley 12-345+ in tank pump
- Gas N side pipes

The engine has been run 4 or 5 times now for short periods of time, but I haven't let it come up to temp as I hadn't burped the coolant system. As I was burping it today, I noticed..
- The fan came on @ 175F
- Fuel pressure on the regulator seems fine (~50PSI)
- The O2 sensor on the Edelbrock ECU got to green, showing it's optimizing the fuel mixture, I'm assuming

But I noticed that as the engine came up to temp, a tapping sound started in the engine bay. My plan is to let the engine cool off this afternoon and then check all fluids / places where maybe the tapping could just be a rattle from something loose / rubbing in the engine bay. But also wanted to see if anyone recognizes the tapping from the video below. I'm an engine novice and Dr. Google had me scared about it being oil levels, oil pressure, exhaust leaks, bad fuel injectors. You name it.

I've added a video below.
https://www.youtube.com/shorts/exlZkxlLOaU

On a somewhat related note, putting the car in gear and driving it for the first time feels like a big milestone and one I'm nervous about. Ya know, cause there's this spinning chunk of metal directly next to my right leg in the tunnel. What are the last things all of you checked before you moved the car on its own power? Driveshaft angle has been checked and the bolts have been loctited.

[JMD]

There's not a dent in oil pan is there? I had an engine that I swapped years ago that had a shallow dent in the oil pan incurred while in transit. Upon starting, the engine had a very similar knock and it turned out the crank was barely contacting it or the windage tray on each revolution. I had to take it off and hammer it back into shape. That's probably not what's going on here, but that's what that noise reminded me of.

Good luck!

[gbranham]

I have a 427 with ProFlo4 and love it. Bump up your fuel pressure to 58PSI. Also, check the fuel pressure sender at the front of the passenger fuel rail. Mine developed a leak after several heat cycles. It just needed to be snugged up. Can't tell what the noise is, but I assume you set your base timing to 12 degrees while the Proflo4 app was running and set to "unlocked" in the timing menu? Sure you don't have a rocker that's a bit loose?

[tnt_motorsports]

a stethoscope can help to narrow down the location and possible source. A long screw driver to the ear can work in a pinch as well.

It is inconsistent meaning it comes and goes. Is something loose? Is a header or side pipe against something metal?

If you vary the RPM does the sound change?

[FDLWproject]

I have a 427 with ProFlo4 and love it. Bump up your fuel pressure to 58PSI. Also, check the fuel pressure sender at the front of the passenger fuel rail. Mine developed a leak after several heat cycles. It just needed to be snugged up. Can't tell what the noise is, but I assume you set your base timing to 12 degrees while the Proflo4 app was running and set to "unlocked" in the timing menu? Sure you don't have a rocker that's a bit loose?

Ah it’s hard to find PF4 folks here. This is super helpful. I’ve not adjusted my fuel pressure after Forte ran it on the dyno. I’ll adjust it upwards. Think I’m just starving the engine?

Funny you mention the fuel pressure sensor on the rail. After playing whack-a-mole with some fuel line leaks, that was the most recent one I fixed this week. Was it the sensor going into the aluminum fitting that was leaking for you too? I cleaned off whatever sealant was there before and used some Loctite that is rated for fuel and it seemed to fix that issue.

On your last comment, I haven’t done any changes to the base timing or any changes using the app. Like I said, novice engine competency so I’ve not checked rockers and would probably farm that out to someone so I don’t screw it up!

[FDLWproject]

There's not a dent in oil pan is there? I had an engine that I swapped years ago that had a shallow dent in the oil pan incurred while in transit. Upon starting, the engine had a very similar knock and it turned out the crank was barely contacting it or the windage tray on each revolution. I had to take it off and hammer it back into shape. That's probably not what's going on here, but that's what that noise reminded me of.

Good luck!
I don’t see any dents but need to jack it up to confirm. Thanks!

[FDLWproject]

a stethoscope can help to narrow down the location and possible source. A long screw driver to the ear can work in a pinch as well.

It is inconsistent meaning it comes and goes. Is something loose? Is a header or side pipe against something metal?

If you vary the RPM does the sound change?
The variable timing is what I noticed too. Which is what made me think it’s something tapping that’s not engine related. Once I run it again I’ll check. Nothing obvious stands out from a look around.

[gbranham]

Ah it’s hard to find PF4 folks here. This is super helpful. I’ve not adjusted my fuel pressure after Forte ran it on the dyno. I’ll adjust it upwards. Think I’m just starving the engine?

Funny you mention the fuel pressure sensor on the rail. After playing whack-a-mole with some fuel line leaks, that was the most recent one I fixed this week. Was it the sensor going into the aluminum fitting that was leaking for you too? I cleaned off whatever sealant was there before and used some Loctite that is rated for fuel and it seemed to fix that issue.

On your last comment, I haven’t done any changes to the base timing or any changes using the app. Like I said, novice engine competency so I’ve not checked rockers and would probably farm that out to someone so I don’t screw it up!

Yep, mine was leaking where you describe it. Did Forte install your ProFlo4 for you before he dynoed it, or did you install it? If he did, I'm sure he set it up correctly; he knows what he's doing, for sure. If you installed it, you definitely need to set your base timing and let the ProFlo4 app know you've done that. But, you might check with him on the sound you're hearing, since he provided the engine. There's more ProFlo4 peeps here than you might realize. Feel free to give me a call if you have any questions. I'll PM you my cell number.

Greg

[John.Gallegos415]

I may be crazy but the tapping sound seems to correlate with the movement of the black pulley with white dot and 4 white arc stripes on the front of the engine.

[Railroad]

For possibilities, consider an exhaust leak. It is easy to check and will take one item off the list.
Get a section of hose, heater hose, garden hose, vacuum hose, etc, one end to your ear the other making a slow sweep of the header flange on the engine.
good luck,

[gbranham]

Railroad has a good suggestion, and a quick, easy check. Snug your header bolts; they can certainly loosen up a bit after a few heat cycles.

Once thing I thought of last night...my stainless steel braided fuel line that was routed from my fuel pressure regulator on the firewall to the front of the passenger side fuel rail on the Pro-Flo4...it was sitting in the valley between the passenger side valve cover and the intake manifold. It was vibrating against the valve cover at idle, and making a somewhat similar knocking sound. I put a small length of split rubber hose on the fuel line where it came in contact with the valve cover, and that stopped that rattle.

Greg

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[Avalanche325]

I agree that it could be an exhaust leak. They can sound like a lifter. Very common after a couple starts.