Stains on crank

[SludgeWizard]

Hey y’all. Opened up my oil pan today to make sure nothing is wobbly on the bottom end and to knock some dents out of the pan, found these stains on the crank shaft and one of the piston caps. Something to be concerned about? The piston stains have texture and catch the nail, the crank do not. Also found a windage tray, were they standard on 73 440s or does that indicate some performance upgrades? It has a “purple” cam in it so I wouldn’t be surprised but this engine is a mystery to me. Some positives though, the tension on the timing chain is perfect and overall the bottom end is entirely solid and clean, no sketchy movement. I think this engine has been worked and overhauled, but what do I know!

 

[halifaxhops]

Looks like it was stored upright for a while and the oil coating dripped off?

 

[SludgeWizard]

Looks like it was stored upright for a while and the oil coating dripped off?

That tracks, the PO replaced it with a stroked 383 and then it sat for a year in his garage

 

[1970FuryConv]

That tracks, the PO replaced it with a stroked 383 and then it sat for a year in his garage

You have a cast crank, so doubt it's a factory HP motor.
Windage tray and purple cam indicate that someone tried to upgrade the engine.
1973 non-HP engines had low compression, ballpark 8.0:1. That engine is not going to have any torque until you raise compression to at least 9.0:1. Advise replacing the pistons.
How do the crankshaft journals look?
Were you able to free the engine after being stuck?

 

[SludgeWizard]

You have a cast crank, so doubt it's a factory HP motor.
Windage tray and purple cam indicate that someone tried to upgrade the engine.
1973 non-HP engines had low compression, ballpark 8.0:1. That engine is not going to have any torque until you raise compression to at least 9.0:1. Advise replacing the pistons.
How do the crankshaft journals look?
Were you able to free the engine after being stuck?

I didn’t pull the main caps to take a look at the journals as I was pushed for time today, that’ll come tomorrow perhaps. I saw writing on the back of the pistons in sharpie, could indicate that the pistons have already been replaced? And this engine is replacing the stuck one currently in my Fury, it’s spun freely since I got it!

 

[1970FuryConv]

I didn’t pull the main caps to take a look at the journals as I was pushed for time today, that’ll come tomorrow perhaps. I saw writing on the back of the pistons in sharpie, could indicate that the pistons have already been replaced? And this engine is replacing the stuck one currently in my Fury, it’s spun freely since I got it!

Anything is possible.
Are there any stamped numbers on top of the pistons?
Are there ring ridges at the top of the cylinders?
You can measure amount piston below deck with a deck bridge like this.
Summit or Wallace Racing have a compression calculator.

 

[SludgeWizard]

Anything is possible.
Are there any stamped numbers on top of the pistons?
Are there ring ridges at the top of the cylinders?
You can measure amount piston below deck with a deck bridge like this.
Summit or Wallace Racing have a compression calculator.
View attachment 751794

I didn’t intend on pulling the heads, but I have borescoped the combustion chambers out and there didn’t appear to be ridges. The walls of the chambers were actually surprisingly clean, visible crosshatch and all. I can check tomorrow for stampings on the face of the cylinders w/ the borescope

 

[73Coupe]

I saw writing on the back of the pistons in sharpie, could indicate that the pistons have already been replaced?

Probably so...vendor's marks or builder's scribbles. Look for writing on the crank too, to see if it's been ground. Usually on a front counterweight.

 

[SludgeWizard]

Probably so...vendor's marks or builder's scribbles. Look for writing on the crank too, to see if it's been ground. Usually on a front counterweight.

Might have actually made a sound financial decision for once lol, I’ll check for any other scribblings tomorrow after work and update the thread

 

[CBODY67]

If it spins over and the heads are on it, you can use a dial indicator or digital caliper to see what the max valve lift is. Then check the Mopar Perf catalog for those numbers. Add a degree wheel and you can find the cam specs pretty easily, after #1 TCD is determined.

Stains on the counterweights will probably wipe off with carb cleaner? Might the sharpie markings be numbers as to piston weights for balancing or bore size for honing?

"somebody" has been there and left evidence.

Enjoy!
CBODY67

 

[SludgeWizard]

If it spins over and the heads are on it, you can use a dial indicator or digital caliper to see what the max valve lift is. Then check the Mopar Perf catalog for those numbers. Add a degree wheel and you can find the cam specs pretty easily, after #1 TCD is determined.

Stains on the counterweights will probably wipe off with carb cleaner? Might the sharpie markings be numbers as to piston weights for balancing or bore size for honing?

"somebody" has been there and left evidence.

Enjoy!
CBODY67

Would you mind expanding on using a digital caliper to find the max valve lift? I’m extremely curious about the cam in this thing, and I’m completely clueless when it comes to finding lift and duration on cams

 

[CBODY67]

What I did was on a 440 short block with no cam or heads. I got a degree wheel (Mr. Gasket) and used a magnetic base dial indicator to set the bent-wire indicator to "0" degrees at full #1 TDC. Then I put a cam in the motor, added a valve lifter and a pushrod so I could check lobe lift and open/close/max lift events. Using the magnetic base dial indicator. Past that, it was just rolling over the motor and writing down numbers. Of course, "lobe lift" x 1.5 = valve lift".

With the heads on the motor, same basic thing. You can remove the #1 spark plug and use a "tool" to find TDC. Then install the degree wheel on the crank nose, set the indicator for TDC, and same thing. Except you'll measure the open/close/max lift events directly from the valve spring retainer. Might need to use a solid lifter rather than a hydraulic? Due to the addition of valve spring pressure?

There is a SAE spec for when to start measuring lifter movement from zero. Like .006" on intake and .008" on exhaust?

With all fo the open/close degree numbers written down, then you can basically build a "cam card" for the cam. You can also calculate the lobe centerlines and such, too.

Getting "lost in the math" can take longer than getting the numbers in the first place. An interesting way to spend a few hours in the shop, too! Actually accomplishing something rather than not, if that matters.

Some digital calipers have a strong piece of wire which can be used to measure depth, as the head measures width. Multi-functional. With the mag-base dial indicator, you'll need to zero the gauge before rolling the engine over to measure valve lift.

Enjoy!
CBODY67