Need help again - Torque specks for flywheel - 8v71

[dreamweaver]

I finally got my new clutch parts for my MC-7 sent to me here in Yuma. I had to remove my flywheel to replace the surface plate so I looked in my book today to get the torque specks but I can't find them. Another question I need to ask is should I change the flywheel bolts or can I use locktight and re-use them? I built the tranny dolly from the book and boy does it ever work slick, sure makes the job a lot easier.I sure hope it goes in as easy as it came out.
I had the pressure plate set to MCI specks so it should work like a charm.If I can find the torque specks for the flywheel ,surface plate and pressure plate I should get this thing on the road again. If anyone has any advice I sure can use it.

Thanks for all the help 
Dave - Dreamweaver

[Hartley]

My book says 35 to 40 ft lbs for the pressure plate to flywheel bolts.

I hope that's right. That's what I have used in the past and didn't have any problems.

You should use only New Bolts and Lock Washers. The old ones are stretched and may be tired and break
when you try to tighten them properly.

Someone else should verify just to be sure....

[Len Silva]

The one thing I have always heard is new bolts every time on the flywheel, and buy them from DD.  Don't take a chance on bolts from an unknown source.

Len

[RJ]

Dave -

Flywheel to crankshaft = NEW bolts from DD.

Pressure Plate to Flywheel = New bolts, either from DD or MCI.

IIRC, torque specs for flywheel to crankshaft are in the DD manual, not the MCI.  Don' t have mine handy right now (they're in the bus), but somebody should.

FWIW & HTH. . .

[SkipN]

When in doubt, no clear answer, or if no manuals available you should be safe using these three links

Bolt classification:
   http://www.tessco.com/yts/customerservice/techsupport/whitepapers/pdf/bolt_grade.pdf

  Torque chart:
  http://www.thelenchannel.com/1torque.php  (max more will snap the bolt)
  http://go.mrgasket.com/pdf/fasteners.pdf
  If you compare the two charts you will see there is some diffs.

   Remember dry is different than oiled. For new bolts only.

Skip

[larryh]

Flywheel bolts are you talking bolts of pressure plate to flywheel then on your model 30 - 35 Foot pounds and rub them up by alternating around the flywheel don't just start at one side and tighten each one in succession alternate across from each one take more time but does it the right way.

LarryH

[rv_safetyman]

Dave, if this is for the flywheel to crank, that is not correct.  My book indicated some fairly low torque and I did not buy the value.  I got on the board and someone pointed me to the DD website.  There I found that the application was to apply the fairly low torque and then rotate the bolt another 120 degrees.  My manual left out the second step

Sorry, I am on the road and don't have the specific web location, but you could do a search once you get there.

UPDATE:  These things drive me crazy (should I say crazier?).  I could not just drop it, so I did a quick search and found the following bulletin:

http://www.detroitdiesel.com/public/sibs/sibs/5-71-00a.pdf

Hope that helps.

[larryh]

If you will read my post I was talking about the bolts pressure plate to flywheel not flywheel to crank big difference here.

LarryH

[rv_safetyman]

Larry, I did not mean to upset you.  Yes, I noted the difference. 

As I look back on the posts, both of the torque suggestions were for the pressure plate to flywheel.  The problem is, those values are close to what DD says to START the torquing process for the crank/flywheel.  In my case, the book did not include the second step (120 rotation) and that could easily lead to confusion.

I just wanted to make sure that Dave got good information on the crank/flywheel since there is has been some very troubling, incorrect, information published by DD in at least one manual.

Jim

[larryh]

Not upset but the info got all muddied up and just pointing out that it was pressure plate to flywheel hate to see a persons flywheel come loose as it means big dollars and usually a new crank my 2 cents I'll bow out and leave it to more experienced person .

LarryH

[dreamweaver]

Sorry for the confusion, I did mean the flywheel to the crankshaft. I did them the DD way. I tightened them to 50 lbs then turned 120 deg., thanks for all your help,it's nice to have a place to turn when one is in need

Thanks everyone
Dave