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FRENCHBLUE72 · 03-23-2004, 11:55 PM

I am rebuilding the lower end in a 350 and when I put the rod bearing's in and torque them to 35 pound's the motor will not rotate the only thing I can think of is the bearing's that came in the kit are wrong... What are these bearing's??? they are the old one's outta the motor..
D.A.B. 51
7555 CAP
7-30 L1
8-30 DA-49

Are they 30 over???

And yes they are 3/8 rod bolt's..

FRENCHBLUE72 · 03-24-2004, 12:27 AM

The head's are still on it and the spark plug's are removed... Main bearing's have not been touched..

68plus4sub · 03-24-2004, 12:57 AM

Did you use plastic-guage to check the clearances? Also, this may be a dumb question, but did you use assembly lube? I can't tell you what the part numbers are, but I always check all bearing clearances even if I know the bearings are suppose to be the right ones. I usually don't have the money to replace new parts that I might mess up, so I always take the extra time.

bigjimzlll · 03-24-2004, 01:25 AM

OK....do you have the right rod on the right side of the journal? If you look at the rod, one side has a radius on it..the other side does not..the radius side goes towards the out side..the 2 flat sides go together..if they are facing the wron way...you wont be able to turn the crank

**GSFMECH** · 03-24-2004, 01:50 AM

FRENCHBLUE72, If the old ones were .030 over and your new ones were standard ( and if the crank is standard) it would be way loose. It sounds like your new ones must be oversize. They usually have the size on the back of the shell. As bigjimzlll said if you get em wrong way around it could cause it to lock up. Be sure the tangs are on the same side when you put it together. It will pay to mic the crank and go back and to the parts store and be sure you get the right bearings. Most good machine shops will stamp the crank if they turn it so you may want to give it a close inspection, that may turn up some info. Plasti-gauge it when you put it together to be sure you have the right clearance, it's a super cheap way to be sure. Plasti-gauge cost less than 2 bucks. Hope this helps,
Mike

angelsairman · 03-24-2004, 02:19 AM

had this problem on the first 350 I built too, i had changed the rod bolts myself and didnt have them realigned or something like that, so they were slightly torqued to one side or another causing binding. Just my 2 cents

Cat Fuzz · 03-24-2004, 02:28 AM

If you got the caps mixed up, that can cause binding. The rod caps must go back on the rods they came off of. Same with the main caps.

FRENCHBLUE72 · 03-24-2004, 09:28 AM

I am gonna barrow a mic from work and see what's up... the new bearing's are 30 over and I never had the rod's outa the block and only removed one cap at a time... When I loosened the rod bolt's the crank freed up so I am guessing maybe I had the cap's cocked... I have never had this problem before thak's guy's I keeep ya posted..

**GSFMECH** · 03-24-2004, 10:50 AM

FRENCHBLUE72, I'm betting your crank is standard and with those .030" over bearings it will lock up the crank for sure. Let us know how it comes out.

Mike

03-23-2004, 11:55 PM	#1
FRENCHBLUE72 PROJECT 7DEUCE Join Date: Dec 2002 Location: GRANTS PASS OR Posts: 21,606	? For The Motor Guru's.. I am rebuilding the lower end in a 350 and when I put the rod bearing's in and torque them to 35 pound's the motor will not rotate the only thing I can think of is the bearing's that came in the kit are wrong... What are these bearing's??? they are the old one's outta the motor.. D.A.B. 51 7555 CAP 7-30 L1 8-30 DA-49 Are they 30 over??? And yes they are 3/8 rod bolt's.. __________________ GO BIG GREEN GO DUCKS MEMBER #6377 72 k-5 daily driver 6'' lift 35'' 350-350-205 slowly getting rust free. Project "7DEUCE" check out my build http://67-72chevytrucks.com/vboard/s...d.php?t=267665 Tim Powell..R.I.P EastSideLowlife..... R.I.P..

03-24-2004, 12:27 AM	#2
FRENCHBLUE72 PROJECT 7DEUCE Join Date: Dec 2002 Location: GRANTS PASS OR Posts: 21,606	The head's are still on it and the spark plug's are removed... Main bearing's have not been touched.. __________________ GO BIG GREEN GO DUCKS MEMBER #6377 72 k-5 daily driver 6'' lift 35'' 350-350-205 slowly getting rust free. Project "7DEUCE" check out my build http://67-72chevytrucks.com/vboard/s...d.php?t=267665 Tim Powell..R.I.P EastSideLowlife..... R.I.P..

03-24-2004, 12:57 AM	#3
68plus4sub Registered User Join Date: Jan 2004 Location: Portland, Oregon Posts: 210	Did you use plastic-guage to check the clearances? Also, this may be a dumb question, but did you use assembly lube? I can't tell you what the part numbers are, but I always check all bearing clearances even if I know the bearings are suppose to be the right ones. I usually don't have the money to replace new parts that I might mess up, so I always take the extra time. __________________ 1972 Chevrolet Suburban ('68 front clip), 2wd, 350/350, factory tilt 2008 Kawasaki Concours 14 1997 Harley-Davidson Soft Tail Custom 1948 Chevrolet Coupe (project) 1972 Porsche 914

03-24-2004, 01:25 AM	#4
bigjimzlll Senior Member Join Date: Dec 2001 Location: Redding,CA...USA Posts: 4,736	OK....do you have the right rod on the right side of the journal? If you look at the rod, one side has a radius on it..the other side does not..the radius side goes towards the out side..the 2 flat sides go together..if they are facing the wron way...you wont be able to turn the crank __________________ It's called "drag racing" if they called it "tic..tic..WHAM!..BANG! F*&K!!!", they'd have to keep the magazines under the counter with the other men's publications click the clicky to join the site.... http://67-72chevytrucks.com/vboard/payments.php 67 lwb..first hotrod in 25 years..540 best ET is 9.45 @ 141.44 Anderson,CA

03-24-2004, 02:19 AM	#6
angelsairman Future Owner Join Date: Jul 2003 Location: Grand Forks AFB, ND Posts: 151	had this problem on the first 350 I built too, i had changed the rod bolts myself and didnt have them realigned or something like that, so they were slightly torqued to one side or another causing binding. Just my 2 cents __________________ Its not the end result that counts most...its the journey along the way that's most rewarding My truck doesn't leak, it just marks it's territory

03-24-2004, 01:50 AM	#5
GSFMECH On the road Join Date: Jan 2004 Location: NATCHITOCHES LOUISIANA Posts: 818	FRENCHBLUE72, If the old ones were .030 over and your new ones were standard ( and if the crank is standard) it would be way loose. It sounds like your new ones must be oversize. They usually have the size on the back of the shell. As bigjimzlll said if you get em wrong way around it could cause it to lock up. Be sure the tangs are on the same side when you put it together. It will pay to mic the crank and go back and to the parts store and be sure you get the right bearings. Most good machine shops will stamp the crank if they turn it so you may want to give it a close inspection, that may turn up some info. Plasti-gauge it when you put it together to be sure you have the right clearance, it's a super cheap way to be sure. Plasti-gauge cost less than 2 bucks. Hope this helps, Mike

03-24-2004, 02:28 AM	#7
Cat Fuzz My son, my joy. Join Date: Sep 2003 Location: Spokane WA Posts: 463	If you got the caps mixed up, that can cause binding. The rod caps must go back on the rods they came off of. Same with the main caps.

03-24-2004, 09:28 AM	#8
FRENCHBLUE72 PROJECT 7DEUCE Join Date: Dec 2002 Location: GRANTS PASS OR Posts: 21,606	I am gonna barrow a mic from work and see what's up... the new bearing's are 30 over and I never had the rod's outa the block and only removed one cap at a time... When I loosened the rod bolt's the crank freed up so I am guessing maybe I had the cap's cocked... I have never had this problem before thak's guy's I keeep ya posted.. __________________ GO BIG GREEN GO DUCKS MEMBER #6377 72 k-5 daily driver 6'' lift 35'' 350-350-205 slowly getting rust free. Project "7DEUCE" check out my build http://67-72chevytrucks.com/vboard/s...d.php?t=267665 Tim Powell..R.I.P EastSideLowlife..... R.I.P..

03-24-2004, 10:50 AM	#9
GSFMECH On the road Join Date: Jan 2004 Location: NATCHITOCHES LOUISIANA Posts: 818	FRENCHBLUE72, I'm betting your crank is standard and with those .030" over bearings it will lock up the crank for sure. Let us know how it comes out. Mike



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