Not sure what section to post this in. Was going to tackle 6cyl starter shims tonight but something else broke. Drove my 57 to work and when I was backing into the yard I could hear a rattle. Sounded kinda like piston slap but not the quite the same tone. Checked the car over for about 1/2 hr but still couldn't figure out where the noise was comming from, thought maybe water pump but it wasn't leaking and could't make shaft move by grabing fan blades. Got home ran with belts off, noise almost stopped. Pryed on dampner pully and it moved about 3/16 side to side. Had the motor rebuilt about 4 years ago and they put a 350 balancer on it without drilling and tapping the crank. I'm thinking that that the bigger heavyer 350 balancer should be bolted to the crank? Has anyone done this ( drill/tap front of crank ) any input would be appreciated need to fix asap. Thx Jim
I've done several in my day, no big problem. From memory, the proper bolt is a 7/16" fine thread, best to get a proper good used bolt and washer from a 350, rather than a hardware store bolt.
Cranks drill surprisingly easy, you need to drill a pilot hole say 3/8" then finish hole of 25/64" ( I had to look that one up)
Follow all precautions and use drilling/tapping oil and take your time threading the hole as a broken tap is a big deal.
Keep removing and cleaning the tap as you go, and did I mention, don't break it off!!
I would pull the damper off and determine which is worn, the crank or the damper. Even bolted on, if its worn that much side to side, its still probably going to rattle
If the harmonic balancer is worn you could try a sleeve for a temporary fix. If it is the crank try some epoxy for a temporary fix. Both fixes are just buying some time although the sleeve will last for quite a while.
Thanks for the tips, I will mic the crank and compare to my other 283's, but it does look like the balancer is worn. Does anyone know aprox depth of hole when drilling? All my stuff is to old and doesn't have a bolt in the front. Thanks Randy, I do have a good walter 7/16 nf tap and 25/64 bit. Thanks Jim
Thanks for the tips, I will mic the crank and compare to my other 283's, but it does look like the balancer is worn. Does anyone know aprox depth of hole when drilling? All my stuff is to old and doesn't have a bolt in the front. Thanks Randy, I do have a good walter 7/16 nf tap and 25/64 bit. Thanks Jim
Couple of tips if you don't already know.....if you drill a little deeper you'll be able to get full threads further in the hole.
The use of a bottoming tap will make sure the full threads go closer to the bottom of the blind hole.,but when using a tap in a "new" blind hole don't use a bottoming tap to start, too much stress on the tap,use a taper or plug tap.
And as mentioned,clean out the hole and lubricate as you go further into the hole.Taps are hardened and a broken tap is a nightmare to remove.
And when all done and cleaned out put a bit of Lock-tite on the threads to secure the bolt from vibrating out of the piece.
-- Edited by Greaser on Wednesday 30th of July 2014 02:12:29 PM
Thanks for the info and tips Randy/George, will tackle tonight and take my time doing so. Think I might have a 7/16nf bottoming tap as well, also orderd a new balancer. Will let you know how I make out. Thx Jim
Got it drilled, tapped and put back together. Took over 1/2 hour to tap 1 hole but alot faster than if I'd broke the tap. Couple of questions 1-how far should the damper be pressed on the crank? I still have 7/16-1/2 inch of shoulder showing and the back of the damper is flush with the timming tab. But seems to be the right spot for the pulleys to line up. 2- Should I press damper on more and get new pulleys or make up a spacer for between damper and pullys? When the motor was rebuilt they put a 350 damper on, should they have used the 350 pullys? The whole setup just doesn't seem right to me. Thx Jim
-- Edited by hawkeye5766 on Thursday 31st of July 2014 01:13:38 AM
It's on now but it would be probably best to pull the damper and measure how far back the crank gear is, as the damper is supposed to bottom out against the gear. By verifying the depth of the gear you can determine how far the damper is to go on. You can make a damper installation tool or use one from the parts store but do not pound the damper on as it damages the thrust bearing portion of the main bearings letting your crank walk.
Will remove and measure. Not that big of a deal just have to drain and remove rad and belts. Will also check with a couple of buddy sand see if I can find a more offset pully. Have a nice long 7/16nf threaded rod that I screwd into crank and then put nut/washer on to install balancer. Thx Jim
