identify cast or forged

-
mopar373

mopar373

FABO Gold Member
FABO Gold Member
Joined
Jul 10, 2011
Messages
762
Reaction score
64
Location
punta gorda fl
I am wondering if anyone knows a way to identify a cast or forged crank while still in the motor????? Thanks AL
 
I know how to tell the difference out of the motor. Is there way to tell when still in the car????
 
1521.jpg


..in case of a 340
 
If the engine is factory original - probably by identifying the balancer used. If it's been rebuilt - no.
 
I have an engine of unknown origin with an extreme vibration 340 I'm thinking that it may have a cast crank and internally balanced parts hung on it.
 
could be a number of issues. wrong torque convertor, wrong balance on drive shaft, wrong balancer, wrong crank, wrong flex plate.
I once bought a valiant with a 360motor and 318 trans. took my a while o figure out what was out of whack, but in the long run it was a cheap fix by buying a balance weight kit and welding the torque convertor.
take a picture of the balancer and post it to start, then remove trans inspection cover and inspect for balance weights on the torque convertor. also look on the side of the block for a casting date.
This is some place to start for now report back what you find and post pix if you can.
 
Take the crank out and drop it on your foot. If it hurts real bad, it's forged, if it doesn't hurt as much as the forged, then it's cast....
 
krazykuda said:
Take the crank out and drop it on your foot. If it hurts real bad, it's forged, if it doesn't hurt as much as the forged, then it's cast....
Click to expand...


If it goes "Clang" it's cast. If it goes "Ring" it's forged...
 
moper said:
If it goes "Clang" it's cast. If it goes "Ring" it's forged...
Click to expand...

nope nodular ford cranks ring and are cast. as do many other cast cranks ring.

if you can drop the pan enough to see the casting line on one of the crank counter weights is best. cast will be a small casting line about 1 mm thick or hairline casting mark.. forged will have a wide 1/2" marking on its casting line. thats the easy way to tell. may be able to use scope to look through the drain plug hole im guessing?
 
turbofreek said:
nope nodular ford cranks ring and are cast. as do many other cast cranks ring.

if you can drop the pan enough to see the casting line on one of the crank counter weights is best. cast will be a small casting line about 1 mm thick or hairline casting mark.. forged will have a wide 1/2" marking on its casting line. thats the easy way to tell. may be able to use scope to look through the drain plug hole im guessing?
Click to expand...

You're obviously not dropping it from high enough :)
 
It may have a 360 balancer and or converter on it. I was thinking the 318 and 340 cast crank engines balance internally as do the forged. If that is so the converter shouldn't have any large weights on it either. (340 balancer may have designation of "cast crank")
The early 360 balancer looks the same from the front but will have material removed from the back side on one half of it.
 
ha! Ibought and drug" almost" home a 68 GTX, buddy bought it off me on way home. ran great when I drove it 55. he took it out to the Interstate one night to "open" it up, had pretty good vibration, he tore it down to find 7 oem 440 rods and 1 six pack ( heavy) rod!! ha
 
mguner said:
It may have a 360 balancer and or converter on it. I was thinking the 318 and 340 cast crank engines balance internally as do the forged. If that is so the converter shouldn't have any large weights on it either. (340 balancer may have designation of "cast crank")
Click to expand...

The 318 cast crank is physically different than the 340 cast crank. The 318 will still be internally balanced the 72-73 340 are external and have a special dampers as you noted that says to "use with cast 340 crank only"

The only way to know what it is, is pull the pan, even then who knows A Balance job would seal the deal.
 
mguner said:
It may have a 360 balancer and or converter on it. I was thinking the 318 and 340 cast crank engines balance internally as do the forged. If that is so the converter shouldn't have any large weights on it either. (340 balancer may have designation of "cast crank")
The early 360 balancer looks the same from the front but will have material removed from the back side on one half of it.
Click to expand...
Though the 340 sometimes even has the same PN crank as the 318 it is externally balanced in a 340 while internally balanced on a 318. Had plenty of cast 318s, have a '71 dated (obviously a '72 motor) cast crank 340 now.
 
You must log in or register to reply here.
-

Back
Top