30 over SBC 400 Not Balanced ? Help! - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 05-15-2012, 01:04 PM
Registered User
 
Join Date: Apr 2012
Location: Mass
Posts: 9
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
30 over SBC 400 Not Balanced ? Help!

Got my 30 over chevy 400 Long Block delivered today from a busy shop in Maine. It is very close to being a stock rebuilt except for a used Eagle crank and used Vortec Heads. Off the Pallet its the wrong color, metal filings in the water jackets, ok: no big deal.. But it didnt have an External balancer or the flex plate installed as we agreed on. Called the shop and asked whats the deal and they said the just recieved them and will send out to me today. ???? I mentioned that we discussed that the assembly would be balanced as a whole. He says that he has been building motors for 40 years and knows the weights. The 400 external balancer and the flexplate off the shelf is all I need! THis goes against everything I have read here, it should have been balanced as an assembly, right? When I mentioned heavy metels and mallory to be added or removed he didn't get it. We started to argue but I don't have the knowelege, so I cut it short. If he "knows the weights" will I be good installing the off the shelf plate and balancer?? Should I send this giant paperweigh back????? THis blows I need to get this in! What should I do?

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 05-15-2012, 01:41 PM
Registered User
 
Last photo:
Join Date: Jul 2004
Location: At Speed
Age: 51
Posts: 1,396
Wiki Edits: 0

Thanks: 2
Thanked 41 Times in 39 Posts
GM did it that way, but they were pretty rigorous on specs. The aftermarket parts can be all over the place on weight specs. It may be close enough for a stocker.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 05-15-2012, 02:31 PM
Registered User
 
Last photo:
Join Date: May 2009
Location: S/E Michigan
Posts: 650
Wiki Edits: 0

Thanks: 0
Thanked 9 Times in 9 Posts
It might be ok, or it might not. Did you get a balance tag with the motor?(if not, ask the guy why?)
If you run it and its not right, can you send it back?
Will the builder refund your money?

Filings in the water jackets indicate the motor wasnt cleaned after machining.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 05-15-2012, 06:25 PM
BOBCRMAN@aol.com's Avatar
Member
 
Last photo:
Join Date: May 2002
Location: Holly, michigan
Posts: 8,238
Wiki Edits: 0

Thanks: 30
Thanked 297 Times in 277 Posts
If it were all stock GM parts except the pistons. You could get away with it on a mild street motor.. Now, who's to say what that used Eagle crank was originally balanced to.. Your builder is a hack!!
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 05-15-2012, 08:28 PM
Registered User
 
Join Date: Apr 2012
Location: Mass
Posts: 9
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
No sheet on balance, no part detail (I knew this though going in). He wants me to pay the shipping charges both ways now...............High volume 350 rebuilder, does them for 850 shipped. I'd split the shipping charge even though he didnt do as agreed upon, but both ways isnt happening. He's telling me I just don't want it, meanwhile my ride sits with this motor I have no cofindence in 10" away.

Last edited by dpgoat; 05-15-2012 at 08:37 PM.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 05-15-2012, 08:48 PM
junior stocker's Avatar
Registered User
 
Join Date: Feb 2004
Location: Everett, Washington
Age: 63
Posts: 821
Wiki Edits: 0

Thanks: 0
Thanked 10 Times in 9 Posts
You don't give your location, but the rebuilder is in Maine, and there are shipping charges involved. Like others have said, it "may" be close to a factory balance, but the aftermarket crank is'nt "factory", and new comes with a "target" balance weight. Who knows how close things are. I believe you have been "crank-SHAFTED". Sorry, junior stocker.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 05-15-2012, 10:17 PM
Registered User
 
Join Date: Apr 2012
Location: Mass
Posts: 9
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Exactly, It can't be a factory balance with an Eagle crank in it.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 05-15-2012, 10:45 PM
bracketeer's Avatar
489 Lemans
 

Last journal entry: Street Legal
Last photo:
Join Date: Dec 2004
Location: Courtenay, BC, CehNehDeh
Age: 55
Posts: 2,139
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Does your machinist even have a balancing machine?

A decent balancing machine costs appx $40,000.00. I doubt he even has one. I was trained how to use and operate the CWT 5000 by the inventor of the machine. http://cwtindustries.com/crankshaft%20balancer.htm

Crankshaft counterweights inserts, and rod large ends (rotating assembly) are 99% of the time heavier than the bobweight of your rod small end, piston, rings, and pin (reciprocating assembly). The bobweight is determined by the heaviest rod, piston, and pin. All the rods, pistons, and pins should be shaved down to the lightest rod, piston, and pin.

Your general hack will stop here and consider the motor balanced. So in actuality he has put your motor further out of balance.

To fix this, the crank has bobweights attached to it, to simulate the reciprocating assembly and spun on a balancing machine. This tells you were metal has to be added or subtracted from the rotating assembly to put it in balance with the reciprocating assembly.

On an externally balanced engine the balancer and ring gear (flywheel) are part of the rotating assembly and are necessary to be attached and on the machine for a proper balancing job.
__________________
[URL]http://members.shaw.ca/g.body.building[/URL]

Last edited by bracketeer; 05-15-2012 at 11:12 PM.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 05-15-2012, 11:14 PM
bracketeer's Avatar
489 Lemans
 

Last journal entry: Street Legal
Last photo:
Join Date: Dec 2004
Location: Courtenay, BC, CehNehDeh
Age: 55
Posts: 2,139
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
balance sheet

most shops will not give you a bobweight card. that way you have to come back to them for repairs. that's natural in the business
__________________
[URL]http://members.shaw.ca/g.body.building[/URL]
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 05-16-2012, 06:28 AM
CNC BLOCKS NE's Avatar
CNC Blocks Northeast
 
Last photo:
Join Date: Sep 2006
Location: NORTHEAST
Age: 54
Posts: 1,491
Wiki Edits: 0

Thanks: 1
Thanked 21 Times in 21 Posts
Sounds like the shop does not even balance!!!!
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 05-16-2012, 06:58 AM
bracketeer's Avatar
489 Lemans
 

Last journal entry: Street Legal
Last photo:
Join Date: Dec 2004
Location: Courtenay, BC, CehNehDeh
Age: 55
Posts: 2,139
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
eagle cranks suck

I hate seeing jobs come in with eagle cranks. They do use a target weight for their assemblies. But if you change any one part the crank needs to be rebalanced and the machinist has to work around predrilled holes. On top of that you usually have to add mallory to fix it. Now your crank is getting expensive. Scat does not use target weights. Their cranks have no pre-drilled holes. You can mix and match any parts. Eagle also changed from SRP pistons to Mahl pistons which are way lighter. To compensate for the weight they redesigned their cranks by moving the center counter weight 45 degrees. Now they have a warehouse full of cranks that are no use to them. If you buy a rotating assembly from them and do not have them balance it. They send you the old type crank and you pay your machinst a fortune to make it work. Sorry about high jacking your thread but this is stuff that customers should be aware of.
__________________
[URL]http://members.shaw.ca/g.body.building[/URL]
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 05-16-2012, 09:56 AM
boatbob2
 
Join Date: Dec 2005
Location: north florida
Age: 76
Posts: 1,377
Wiki Edits: 0

Thanks: 6
Thanked 27 Times in 24 Posts
Screwed????????????

You are screwed,ONLY,if you allowed yourself to be. ive been preaching this for years....PAY ONLY BY CREDIT CARD...if you got screwed,let the credit card company fight them..SOMETHING not right??,DITTO,CREDIT CARD COMPANY.......i got tired of being the screwed,now,im the screwee,when things go bad.....
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 05-16-2012, 12:37 PM
Registered User
 
Last photo:
Join Date: May 2009
Location: S/E Michigan
Posts: 650
Wiki Edits: 0

Thanks: 0
Thanked 9 Times in 9 Posts
Take the shipping costs and pay them to a qualified machinst in your area to pull the motor down and balance it properly. You'll be further ahead, and you wont be sticking anymore money in the thiefs pocket.
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 05-16-2012, 08:34 PM
Registered User
 
Join Date: Apr 2012
Location: Mass
Posts: 9
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I took it to the freight terminal and shipped it back. Don't have the time to do this twice.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
externally balanced vs interally balanced? bwomp969 Engine 7 06-15-2009 04:47 PM
400 small block balanced starter ring? Aboveknee Engine 29 07-26-2008 01:16 PM
can a 350 flywheel be balanced for a 383/400? fiscus Engine 4 04-03-2007 08:07 AM
87 SBC 350 Internal / External balanced?? punk1c5040 Engine 11 03-24-2004 08:12 AM
Balanced 400 Flexplate:Counterweight in or out? Mr.56Chevy Transmission - Rearend 3 12-12-2002 12:00 AM


All times are GMT -6. The time now is 07:41 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.