First start!!!!!...5.0 swap...disturbing noises..need advice from engine guys

[skrit]

Amateur rebuilt Explorer 5.0 with rebuilt 4R70W done by me. Finally got my wiring all sorted out. The big night for first start.

Everything factory including exhaust manifolds, original good shape pistons cleaned with new rings, rebuilt valve train. Original cam and crank (polished and new bearings). Honed cylinders. New harmonic balancer. Tolerances in spec when I rebuilt it.

Primed the oil pump 2 weeks ago. I'm using Royal Purple break in oil. Took 3 cranking cycles to I get the fuel and oil flowing right. Fired right up!

But....very noticeable thudding knock sounds at idle at the block. Rev up to around 2000 can't hear it but it's loud so it might be masking it. This is a rolling chassis. Not a valve tick. Note: my exhaust is mocked up with crappy clamps and not complete. I can feel vibration on the engine block.

Would a video with sound help? I know I might have to pull the motor. Could be a spun bearing?

I have a Blue Driver Bluetooth scanner in the ODB2. No faults other than evap stuff I need to work out.

 

[lars]

Video with sound might help. So many possibilities. Loud exhaust doesn't help. Torque converter nuts tight to flexplate? Piston slap (unlikely but possible). Oil pickup tube not fastened to main bearing bolt and rattling around (yes, I've seen that)?

 

[skrit]

@lars You may be right. It sounds like it's coming from the rear of the block but sounds are deceiving. BTW, thanks for the reply! Ya'll let me know if the video is no good.

Here is also a link which I hope works: 939993-283b138428ddc0ca3dd522af2b83ac86.mp4

 

[noslo5o]

Sounds more like a rattle than a knock. I would give all the fasteners a once over and check to see if your missing any tools. A long screwdriver placed to your ear can act like a stethoscope to help you pinpoint the location.

 

[skrit]

Sounds more like a rattle than a knock. I would give all the fasteners a once over and check to see if your missing any tools. A long screwdriver placed to your ear can act like a stethoscope to help you pinpoint the location.

Well said sir. I know about the screwdriver trick. Could be a missing 10mm socket

I'll pull it apart next weekend but wanted to get a feel of what I should be looking for. Just afraid to run it for more than a minute listening for the exact location.

 

[skrit]

I just started it up again and it's definitely coming from the lower....

A while back when I was rebuilding... it was very hard to turn the crank with a torque wrench (i posted about this).... this has to be a reason

 

[badandy73]

Could drop the pan and inspect/ investigate, especially if you think it's coming from the bottom end.

Hopefully it's something simple and you get it figured out... clean looking chassis BTW!

 

[EPB72]

I just started it up again and it's definitely coming from the lower....

A while back when I was rebuilding... it was very hard to turn the crank with a torque wrench (i posted about this).... this has to be a reason

when turning crank was it just the crank or were the rods?pistons connected as well,,, just the crank you should be able to turn by hand,, and the pistons/rods were reinstalled in original locations ? just asking,,, btw the sound clip didnt work for me.

 

[skrit]

when turning crank was it just the crank or were the rods?pistons connected as well,,, just the crank you should be able to turn by hand,, and the pistons/rods were reinstalled in original locations ? just asking,,, btw the sound clip didnt work for me.

It turned easily by hand but once the pistons were in and the heads were on it became very tight.

 

[spap]

I have had a flex plate gear ring semi separate from the flex plate, if it is a rattle . Yours sounds different though but never hurt to check
at least you don’t have the body on… even the new stufff is old stuff

 

[tasker]

SOUNDS like a lower end knock to me...and loud

 

[Speedrdr]

Almost sounds like a loose wrist pin to me …

Randy

 

[DirtDonk]

Is the drive belt installed for the front accessories? If so, remove it temporarily just to eliminate separate items, as well as tension on the crank in one direction.

Are you checking for oil pressure? Do you have gauges connected?

Is there a driveshaft or at least the transfer case attached to the transmission?
Fluid in the transmission?

 

[DirtDonk]

What is your fuel pressure and ignition timing?

 

[DirtDonk]

Ok, I see by pics your other thread that you have the drivetrain installed. So presumably the transmission is in park or neutral, or it might’ve been trying to drive through the wall!

 

[skrit]

I'm going to drop the oil pan and inspect. I'll update with my findings ASAP.

NOTE: I have yet to completely fill the tranny with fluid. Forgot to do that - focusing on the engine. Does the torque converter turn if it's not in gear? I'll fill it up this evening.

 

[DirtDonk]

The torque converter is always turning with the engine.
Remember, the body of the torque converter is rigidly bolted to the flex plate. Which in turn is rigidly bolted to the crankshaft.
So yes, the external components, meaning the main body, is always turning.

What else turns, and does not turn, once it turns the input shaft of the transmission, I do not know.