Torque values and such

Bill Musarra · 3rd July 2010, 01:28 PM

Have just gotten the engine back from a rebuild.Its time to reassemble the drive train and I am having trouble finding the correct torque values. I did a search and still come up with different values. For instance for the 5/8x11 bolts in the flywheel one bolt source says 160(dry)-180(lubricated) and another says just 230 for grade 8. Does lubricated mean oil, grease or loctite?? So I need some imput on that and some other questions. Should Loctite red be used on the flywheel bolts. What about the adapter bolts which are 5/8 also.The half shaft allen bolts(930). Red or blue on them and values?? Since I am not a mechanic I need some direction.

Bill

Mike Huddart · 3rd July 2010, 01:51 PM

Bill,
don't understand your 5/8 x 11 for your flywheel bolts. A SB Ford has 7/16 UNF bolts, torque to 65 ft/lbs and use Loctite or you will get oil seeping through from the crankcase.
Mike

Jac Mac · 3rd July 2010, 03:48 PM

Bill, your motor is a 351W, your flywheel/crank bolt holes (7/16 unf)should be blind & therefore dont require thread sealant. The torque for these is 75/85 ft lbs, the lower figure for Auto Flex plates which quite often use a shorter bolt ( less thread engagement ) and the upper 85 ft/lb for the proper flywheel bolts which should have a plain shank of about 1/4" for a dowel effect before the thread starts and have more thread engagement. These figures are for OE ford bolts, if using ARP or other aftermart hardware follow their torque values/reccomendations.
The 5/8"-11 bolt you refer to might be the central bolt for the crank damper/harmonic balancer, if so torque for it is 130 ft ib...

Bill Musarra · 12th July 2010, 05:44 PM

When we sent the engine for inspection the flywheel was pulled. Now that it is back I looked closer at the bolts in the flywheel. They are indeed 5/8" or 16 mm take your pick. The thread is not npt as 11 and 18 are too coarse. The do however mach up to a 20 pitch. Here are some pics of them. I am assuming that they came from KEP but that was some time ago. The threads have not been touched to my knowledge. they may have been sourced by the shop that installed the trans and finished building the engine. They do a lot of Ford engines for drag and oval racing setups.

Bill

Dave Wharran · 12th July 2010, 09:00 PM

Bill,
ARP's website has some interesting stuff on bolt tightening (stretch vs torque vs torque angle). According to them, "The lubricant used is the main factor in determining friction, and therefore, the torque for a particular installation."
Go to this web page ARP | Tech - Installation and click on "using a torque wrench" in the left column. Plenty of good info there.

Also see this page Automotive Racing Products | ARP Ultra-Torque? for info on ARP Lubricant ( I've heard it called ARP snot). It's good stuff. I used it along with many ARP fasteners on my engine/40.