Jump to content

Recommended Posts

Posted

I am just wondering what someone actually does when they weld and true a crank? Also why is it a good idea to get it done after you port the engine? Any info is appreciated.

 

Also how can you remove the crank, do you have to split the case?

 

The reason I ask is because it isn't too expensive to weld and true the crank, but it is to assemble and disassemble the engine. I am just wondering how much it would cost in the long run to weld and true the crank?

 

Thanks.

Posted
I am just wondering what someone actually does when they weld and true a crank? Also why is it a good idea to get it done after you port the engine? Any info is appreciated.

 

Also how can you remove the crank, do you have to split the case?

 

The reason I ask is because it isn't too expensive to weld and true the crank, but it is to assemble and disassemble the engine. I am just wondering how much it would cost in the long run to weld and true the crank?

 

Thanks.

Welding the crank is when they put a spot of weld every place the crank is pressed together. Keeps it from twisting under high hp. Not too sure what is involved with truing the crank other than making sure the journals and mains are all lined up where they need to go and nothing wobbles out of spec. To weld a crank shouldn't be more than $30. Its not like they are there running a full bead. To true it, again, I have no idea.

 

To disassemble your engine, get a Clymers manual all the right tools, and about an hour. Putting it back together will be a little longer as it always is longer to put something back together than it is to take it apart.

Posted

When truing the crank we use a crank fixture to spin the crank in while using a dial indicator to check for radial and axial runout of the outer flywheels. We shoot for .oo1 or less runout, that equates to less than .ooo5 total(that is 5/10,000 of an in.). The rod side clearance is also set . CEJ is right about the weld, only about a 3/8 in. bead is used on both sides of the crank pins. This will keep the crank flywheels in time (true) and keep them from seperating under high load conditions, like high compression, radical portwork, nitrous..etc.

 

I have a trued and welded crank I can sell you, or I can do your crank.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...