Weekendbob

I recently installed a GM issued flexplate to the LSX crankshaft, using the supplied GM bolts, torqued to GM specs (74 ft/lbs). Given the forces and vibrations involved there, I'm now wondering if I should have used threadlocker? GM bolts have some type of coating on the threads but I'm not sure if it is anti-seize or doubles as thread-locker. Any thoughts? I'd rather not back the bolts back-out to apply locker if I don't have too.

Thanks

Grant@NitroDaves

I have always used loc-tite on flexplate to crank bolts. definitely dont want those to back out. Torque converter bolts too. Ive had those back out on my old Chevelle. made a ton of noise with the converter rattling around on loose bolts.

XtraCajunSS

iTrader: (2)

Grant is right. The factory bolts are supplied with tread locker. Unless you are using ARP's, stick with threadlocker.

Shane

Weekendbob

If "supplied with thread-locker", do you mean in a separate gel pack or the threads are pre-coated from the factory? If they are pre-coated (which may be the substance on the threads I was referring to in my first post) then I should be in good shape.

melsie68

iTrader: (8)

I have been building engines/cars for over 12 years and have NEVER used Loctite or any kind of thread "locker". I have never had an issue with bolts coming loose or working their way out on any part of any engine or in the driveline. I really think it is a bad idea on anything that requires mantainence or review. I can't imagine screwing up the threads in a $1000+ crankshaft. Another one that kills me is the guy who says to use Loctite on rocker studs or rocker bolts. Putting that crap in aluminum threads just wreaks of failure and future heli-coil kits. If the bolts have a torque rating (and all bolts do), they are meant to stretch. The "stretch" of the bolt is what will hold its torque when applied. It is known as a type of tension or elasticity. Use anti-seize and the proper torque and torque method/sequence. You will have no problems coming loose nor will you have problems removing the fasteners when it is time.

XtraCajunSS

iTrader: (2)

The factory bolts have a thread locking compound applied. You should be all set. ARP bolts come with their moly lube and should be torqued to 60 lb/ft with it.

Shane

jay_lt4

iTrader: (4)

some stroker cranks have the bolt holes go all the way through, those you need to use a paste sealant or silicone to prevent oil leaking from the crank/flex plate bolts