Ok so I have a new 383 that is internally balanced and full of nice parts. So to make sure that it lasts a long time I bought the nicest damper I could find. Or at least what I hear is the best. So I order a 7" balancer from summit. I get it open it and start to read the instructions. It says I need to take the thing appart and put it back togeather with loctite. Not a big deal i guess, I just don't want to mess it up. Anyways, that is not the issue. The real issue is that the recomended bore in the damper is said to be a certain # and the that the crank snout needs to be within a certain bore to be press fit. Now my question....

Is it true that you need to have these bored checked to such increadible precition? They are talking about a couple ten thousandths of an inch here.....I really don't want to go deal with finding a shop that can bore out my brand new ATI piece esspecially since I paid neer $300 for it.

Thanks for any insight into the issue.

-Dennis

 

Your balancer should be manufactured to a given (ie crank snout od) tolerance. This would be a press fit tolerance and the manufacturing process should be able to control that. I think what their saying is that they recommend you double check the id and od sizes. They can't control the tolerances of someone elses crankshaft. The balancer needs to be this tight to avoid welding itself to the crank under normal use. If you don't have the right installation tool go to a parts shop that has a "loan a tool" program. Do not beat your balancer on with a hammer and a block of wood. Also put some lubrication on the crank and put a little grease on the balancer seal in the timing cover so you don't melt the seal on initial start up.

 

Thanks for the help. I read in the instructions to lube all those things up. Any recomendations on what is a good lube I can pic up at a parts store? Also do you think that the brand new snout from my eagle forged crank comes close to the ATI recomendations? I know there is no way to tell, but would you think so....... I feel that the crank is new and therefore should be close to perfect. Anyways, thanks for any help.

 

No it should be perfect. Period. These need to be kept to within a few ten thousanths of an inch for exactly the reason we are talking about now. If the snout isn't to size then don't try to install the dampener, you'll just wreck it and/or the crank. No need to purchase any special grease. Just A LITTLE wheel bearing grease or heavy motor oil on the seal and simply motor oil on the snout.

 

Allright. I will pick up a caliper today and measure the snout and the balancer. Man I hope it is prefect allready. (cross my fingers)

 

I had a guy come into the shop on Monday with an ATI balancer that was machined to the wrong size. He spcified the snout diameter to the .0001" and they made it to big. Ate up the hub, and they made him PAY for a new hub, lol, he bought a Fluidamper from us. Make sure you check it! He got luck and it didn't eat up his Callies crank.

 

So the shop made a mistake and him pay for it? Sounds like a very pathetic excuse for a shop.

 

Dennis
See if you can get both an inside mic and an outside mic. They are MUCH more accurate. When your talking in .0001 its to easy to get an incorrect reading on a vernier.

 

gotcha. Will do. I am def not gonna cheap out on the on the damper. i am allready super nevouse that I am gonna mess something up. I would happily spend more $ to have piece of mind. I will pick one up at an parts store today. I guess it will be a nice tool to have in the long run.

 

Ain't gonna be a cheap tool but will be a nice one. Gets put in the delicate tool box drawer.

 

yeah, 40 bucks from jegs. With a nice protective box

 

When I had my motor built, the machine shop had to bore out the balancer a hair to make it all within spec. Its weird how many specs there are when building a motor.

 

damn. Thanks for the info. Now I know this is not uncommon.


still sux

 

Try to find one a little better than that. I'm partial to Starret. It'll come with a standard so you can calibrate it. Not cheap by any means, but well worth it.

 

Thanks for the advice. I am really hurting for $ right now. I have spent around 3 grand in partsin the last month and I need to spend another grand today and then I am out of $ for a while. I am going to see if I can just rent one or something. If not then buy that good one you recomended above. What kinda $ are we talking for a part like that?