Factory 327 engine - The 1947 - Present Chevrolet & GMC Truck Message Board Network

**Classic v6 GMC's** · 12-11-2016, 11:25 PM

Pulled our 63 327 apart today and found some interesting grind marks on the crank. Has anyone else seen marks like this?
The pan looked like it had never been removed. A bad casting at factory?
When we rebuilt our power-glide a few months ago it had some grind marks under the valve body and had been welded on the case by the band servo.

**Classic v6 GMC's** · 12-11-2016, 11:30 PM

Pics

**Captainfab** · 12-12-2016, 12:55 AM

That is definitely a messed up looking crank. Maybe that was done to get the crank in balance specs? I don't think a '63 327 would have come with a double roller timing chain.

luvbowties · 12-12-2016, 07:20 AM

I 2nd ^^^^, plus I surely think it was done after it left the factory.
S

**crossy** · 12-12-2016, 10:50 AM

pull the bearings on at least one rod & main. they will have a have a manufacture on them and a date. that will tell you if anyone has ben in there before. I just pulled apart a 63 SHP 327(it's on ebay now ) with no serial numbers on the front pad, and even though I know it was been where it was for the past 40+ years, I was told it was never apart yet I found the bearings were dated 75. Crossy

**jayoldschool** · 12-12-2016, 12:17 PM

It's been apart previously. Your last photo shows a stamping on one of the counterweights.

andyh1956 · 12-12-2016, 06:45 PM

Just so you know that's a forged crank. You can tell by the wide parting line on the rod throw.

**Classic v6 GMC's** · 12-12-2016, 08:30 PM

Quote:

Originally Posted by Captainfab

That is definitely a messed up looking crank. Maybe that was done to get the crank in balance specs? I don't think a '63 327 would have come with a double roller timing chain.

I was thinking the same thing.
Possibly or maybe for clearance.
I did not think it would have a roller chain either but the 63 data book shows that it would.

Quote:

Originally Posted by luvbowties

I 2nd ^^^^, plus I surely think it was done after it left the factory.
S

I would have thought so to but this engine still had most of the original paint intact.

Quote:

Originally Posted by crossy

pull the bearings on at least one rod & main. they will have a have a manufacture on them and a date. that will tell you if anyone has ben in there before. I just pulled apart a 63 SHP 327(it's on ebay now ) with no serial numbers on the front pad, and even though I know it was been where it was for the past 40+ years, I was told it was never apart yet I found the bearings were dated 75. Crossy

I will next weekend. This engine is out of a original truck and it still had most of the original green paint so I don't think it has been apart.

Quote:

Originally Posted by jayoldschool

It's been apart previously. Your last photo shows a stamping on one of the counterweights.

The factory would not have stamped it? I will get the stamping and post them.

**Classic v6 GMC's** · 12-12-2016, 08:33 PM

Quote:

Originally Posted by andyh1956

Just so you know that's a forged crank. You can tell by the wide parting line on the rod throw.

Yes already looked that up.

jtrichard · 12-12-2016, 09:07 PM

Quote:

Originally Posted by andyh1956

Just so you know that's a forged crank. You can tell by the wide parting line on the rod throw .

Please explain "wide parting line"

**Classic v6 GMC's** · 12-12-2016, 09:44 PM

Here are some more pics.

**Classic v6 GMC's** · 12-12-2016, 09:45 PM

And a few more

**Classic v6 GMC's** · 12-12-2016, 09:48 PM

One counter weight is stamped (2) 3 times
One is stamped 5
One is stamped 8
One is stamped G

Also one of the counter weights has a chalk check mark on it.

LT1 Burb · 12-12-2016, 09:56 PM

My powerglide case a weld on it too, about 1" long.

**Classic v6 GMC's** · 12-12-2016, 10:16 PM

Quote:

Originally Posted by LT1 Burb

My powerglide case a weld on it too, about 1" long.

Yes ours was about an 1" long as well. Might have been a common problem but seemed interesting.

urmyboyblue · 12-12-2016, 10:52 PM

If you don't see what it was grinding against in the oil pan or block, chances are it was a crude attempt to remove metal for balancing. Pretty crude. Probably still usable but i would have the engine balanced if you rebuild it- and checked for cracks. Something got medieval on that crank!

**Classic v6 GMC's** · 12-12-2016, 11:25 PM

Quote:

Originally Posted by urmyboyblue

If you don't see what it was grinding against in the oil pan or block, chances are it was a crude attempt to remove metal for balancing. Pretty crude. Probably still usable but i would have the engine balanced if you rebuild it- and checked for cracks. Something got medieval on that crank!

No grinding on the other parts just the crank so you are probably right. I will defiantly have it checked out.

andyh1956 · 12-13-2016, 12:33 AM

Quote:

Originally Posted by jtrichard

Please explain "wide parting line"

Lookit the second pic in post #11. The wide line on the rod throw that runs 12 oclock to 6 oclock that has the horizontal grind marks on it is the "Parting" line where the forge dies stamped the crank from it's billet. It looks to be 1/2" wide or so. Cast cranks have a very narrow & sharp parting line where the form is broke away from the crank. Cast & forged cranks will have a distinctly different tone when struck with a metallic object.

jtrichard · 12-13-2016, 01:18 AM

"forged cranks will have a distinctly different tone when struck with a metallic object."
I knew that but all the hitting on my screen did NOT result in the tone that I am familiar with LOL
Did not know about the parting though

ryanv70c10 · 12-13-2016, 01:21 AM

Quote:

Originally Posted by andyh1956

Just so you know that's a forged crank. You can tell by the wide parting line on the rod throw.

All small journal 327 cranks were forged IIRC

ryanv70c10 · 12-13-2016, 01:28 AM

Factory small journal rods had 5/16" rod bolts. Those appear to be 3/8" from the pics. What size socket fits on the nut?

**crossy** · 12-13-2016, 01:43 AM

Quote:

Originally Posted by jtrichard

Please explain "wide parting line"

On the roughest part of the throws you will see the parting line as either 3/8" wide(forged) on very thin like 1/16"(cast)

Brad54 · 12-13-2016, 02:23 AM

Some of those pictures almost look like the crank counterweights were "knife-edged," which is an old racer's trick to reduce windage as the crank goes through oil.
It's a lot more crude in places than I've ever seen before, but it definitely looks like it.
That first series of pics also looks like material was missing from the side of the counterweight, like it was a void in the casting, or metal flaked off.

If it balances (which seems hard to believe), and isn't cracked, there's no reason not to run it.
-Brad

gabbin · 12-13-2016, 09:12 AM

I think it would be a good idea to have a machine shop check the balance and for cracks. If it is ok run it, well, as long as it can be turned and cleaned up.

andyh1956 · 12-13-2016, 02:01 PM

Quote:

Originally Posted by jtrichard

"forged cranks will have a distinctly different tone when struck with a metallic object."
I knew that but all the hitting on my screen did NOT result in the tone that I am familiar with LOL
Did not know about the parting though

HAHAHA! Hope you didn't hit it too hard & it's not your WIFE'S computer!

12-11-2016, 11:30 PM	#2
Classic v6 GMC's Senior Member Join Date: Mar 2015 Location: Arizona from Overland Park Kansas Posts: 3,968	Re: Factory 327 engine Pics Attached Images __________________ Current projects: 1966 Chevy Custom PS PB A/C BBW 283 v8 3 speed OD 1966 GMC Long Step 1966 GMC 3/4 ton Custom PS PB Sport trim 351 v6 1966 GMC 3/4 ton 4x4 Custom PB 305 v6 np435 1960 GMC Custom 1968 GMC 3/4 ton 4x4 Short Bed 1962 K20 Tow truck 1961 GMC Extended Suburban Panel and a few more

12-12-2016, 12:55 AM	#3
Captainfab 60-66 Nut Join Date: Mar 2007 Location: Coeur d'Alene, Idaho Posts: 23,252	Re: Factory 327 engine That is definitely a messed up looking crank. Maybe that was done to get the crank in balance specs? I don't think a '63 327 would have come with a double roller timing chain. __________________ Power Steering Box Adapter Plates For Sale HERE Power Brake Booster Adapter Brackets For Sale '63-'66 HERE and '67-'72 HERE and '60-'62 HERE and "60-'62 with clutch HERE Rear Disc Brake Brackets For Sale. Impala SS calipers HERE Camaro Calipers HERE D52 Calipers HERE 6 Lug HERE Hydroboost Mounting Plates HERE

12-12-2016, 07:20 AM	#4
luvbowties Registered User Join Date: Feb 2009 Location: southeasternfoothillsofusa Posts: 1,557	Re: Factory 327 engine I 2nd ^^^^, plus I surely think it was done after it left the factory. S

12-12-2016, 10:50 AM	#5
crossy Oh,you can't buy that new Join Date: Apr 2000 Location: Pennsville,N.J. 08070, USA Posts: 2,039	Re: Factory 327 engine pull the bearings on at least one rod & main. they will have a have a manufacture on them and a date. that will tell you if anyone has ben in there before. I just pulled apart a 63 SHP 327(it's on ebay now ) with no serial numbers on the front pad, and even though I know it was been where it was for the past 40+ years, I was told it was never apart yet I found the bearings were dated 75. Crossy __________________ "been there, done that, ruined the T-shirt". 2007 LBZ GMC Sierra, ECSB 2006 LM7 RCSB Silverado 98 Vortec project. 94,3500,6.5L 4L80 81 SWB GMC POS finally gone 73 Pinto, stock, w/CragarSS's-eww LOTS of Cummins trucks.

12-12-2016, 12:17 PM	#6
jayoldschool Moderator Join Date: Dec 2012 Location: ON, Canada Posts: 2,176	Re: Factory 327 engine It's been apart previously. Your last photo shows a stamping on one of the counterweights.

12-11-2016, 11:25 PM	#1
Classic v6 GMC's Senior Member Join Date: Mar 2015 Location: Arizona from Overland Park Kansas Posts: 3,968	Factory 327 engine Pulled our 63 327 apart today and found some interesting grind marks on the crank. Has anyone else seen marks like this? The pan looked like it had never been removed. A bad casting at factory? When we rebuilt our power-glide a few months ago it had some grind marks under the valve body and had been welded on the case by the band servo. Attached Images __________________ Current projects: 1966 Chevy Custom PS PB A/C BBW 283 v8 3 speed OD 1966 GMC Long Step 1966 GMC 3/4 ton Custom PS PB Sport trim 351 v6 1966 GMC 3/4 ton 4x4 Custom PB 305 v6 np435 1960 GMC Custom 1968 GMC 3/4 ton 4x4 Short Bed 1962 K20 Tow truck 1961 GMC Extended Suburban Panel and a few more

12-12-2016, 06:45 PM	#7
andyh1956 Registered User Join Date: Mar 2010 Location: thomastown mississippi Posts: 1,261	Re: Factory 327 engine Just so you know that's a forged crank. You can tell by the wide parting line on the rod throw.

12-12-2016, 09:44 PM	#11
Classic v6 GMC's Senior Member Join Date: Mar 2015 Location: Arizona from Overland Park Kansas Posts: 3,968	Re: Factory 327 engine Here are some more pics. Attached Images __________________ Current projects: 1966 Chevy Custom PS PB A/C BBW 283 v8 3 speed OD 1966 GMC Long Step 1966 GMC 3/4 ton Custom PS PB Sport trim 351 v6 1966 GMC 3/4 ton 4x4 Custom PB 305 v6 np435 1960 GMC Custom 1968 GMC 3/4 ton 4x4 Short Bed 1962 K20 Tow truck 1961 GMC Extended Suburban Panel and a few more

12-12-2016, 09:45 PM	#12
Classic v6 GMC's Senior Member Join Date: Mar 2015 Location: Arizona from Overland Park Kansas Posts: 3,968	Re: Factory 327 engine And a few more Attached Images __________________ Current projects: 1966 Chevy Custom PS PB A/C BBW 283 v8 3 speed OD 1966 GMC Long Step 1966 GMC 3/4 ton Custom PS PB Sport trim 351 v6 1966 GMC 3/4 ton 4x4 Custom PB 305 v6 np435 1960 GMC Custom 1968 GMC 3/4 ton 4x4 Short Bed 1962 K20 Tow truck 1961 GMC Extended Suburban Panel and a few more

12-12-2016, 09:48 PM	#13
Classic v6 GMC's Senior Member Join Date: Mar 2015 Location: Arizona from Overland Park Kansas Posts: 3,968	Re: Factory 327 engine One counter weight is stamped (2) 3 times One is stamped 5 One is stamped 8 One is stamped G Also one of the counter weights has a chalk check mark on it. __________________ Current projects: 1966 Chevy Custom PS PB A/C BBW 283 v8 3 speed OD 1966 GMC Long Step 1966 GMC 3/4 ton Custom PS PB Sport trim 351 v6 1966 GMC 3/4 ton 4x4 Custom PB 305 v6 np435 1960 GMC Custom 1968 GMC 3/4 ton 4x4 Short Bed 1962 K20 Tow truck 1961 GMC Extended Suburban Panel and a few more Last edited by Classic v6 GMC's; 12-12-2016 at 09:55 PM.

12-12-2016, 09:56 PM	#14
LT1 Burb Registered User Join Date: Sep 2010 Location: Winchester Oregon, formerly Vancouver BC Posts: 2,949	Re: Factory 327 engine My powerglide case a weld on it too, about 1" long.

12-12-2016, 10:52 PM	#16
urmyboyblue Registered User Join Date: Feb 2015 Location: Montevallo, AL Posts: 272	Re: Factory 327 engine If you don't see what it was grinding against in the oil pan or block, chances are it was a crude attempt to remove metal for balancing. Pretty crude. Probably still usable but i would have the engine balanced if you rebuild it- and checked for cracks. Something got medieval on that crank!

12-13-2016, 01:18 AM	#19
jtrichard Registered User Join Date: Jun 2013 Location: joshua tree ca. Posts: 1,484	Re: Factory 327 engine "forged cranks will have a distinctly different tone when struck with a metallic object." I knew that but all the hitting on my screen did NOT result in the tone that I am familiar with LOL Did not know about the parting though

12-13-2016, 01:28 AM	#21
ryanv70c10 Registered User Join Date: Feb 2016 Location: San Mateo Posts: 199	Re: Factory 327 engine Factory small journal rods had 5/16" rod bolts. Those appear to be 3/8" from the pics. What size socket fits on the nut?

12-13-2016, 02:23 AM	#23
Brad54 Registered User Join Date: Aug 2006 Location: Athens, Georgia Posts: 1,458	Re: Factory 327 engine Some of those pictures almost look like the crank counterweights were "knife-edged," which is an old racer's trick to reduce windage as the crank goes through oil. It's a lot more crude in places than I've ever seen before, but it definitely looks like it. That first series of pics also looks like material was missing from the side of the counterweight, like it was a void in the casting, or metal flaked off. If it balances (which seems hard to believe), and isn't cracked, there's no reason not to run it. -Brad __________________ '61 Suburban daily driver: off the road due to 180-pound 8-pt buck! '62 K-10 long-step project '61 C30 Camper, aka "Valdez" There's no cool like Old School



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12-13-2016, 09:12 AM	#24
gabbin Registered User Join Date: Feb 2009 Location: harrah,oklahoma Posts: 89	Re: Factory 327 engine I think it would be a good idea to have a machine shop check the balance and for cracks. If it is ok run it, well, as long as it can be turned and cleaned up.

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