The Stovebolt Site Forums The Shop Area Engine Shop 235 Flywheel bolts-lock plates? Lock Washers? Locktite?

For a '59 235, did the factory use lock plates or lock washers on the flywheel bolts? Are you guys just torquing the bolts, using loctite, lock washers, lock plates?

Thanks

Ron

"All of the above". If a bolt is torqued properly, it won't get loose. If not, there's no type of locking device in the world short of welding it to the flywheel that's going to keep it from coming loose. I use red Loctite on clean threads, torque the bolts evenly, and forget about extra devices. Split lock washers are particularly bad, as they allow oil to creep down the threads and leak into the bellhousing through the split.
Jerry

When I was still working at a nuke power plant, we had training on the importance of torque to spec.
When the proper torque is applied with a Never Seize type lubrication on the threads and on the nut or bolt face, it actually stretches the bolt a given amount.
Lube is really important to get the right torque for the stretch, A dry rusty bolt will hit the torque spec without the proper stretch.
On the reactor cooling pumps seals housing, we used a hydraulic tool that screwed on the stud threads above the finger tight lubed nut and stretched the studs. Pumped it up to some high-pressure stat the procedure listed and then turn the nut to finger tight again, release the hydraulic pressure and then move on to the next studs listed in the bolting sequence. These were on 3 inch studs and Phak1 probably had the same training.
Here a video of a set being used on some small studs.
www.youtube.com/watch?v=yinyrZCvywI

Don

Did you work in Sector 7G?

Never heard of a sector 7G. I was a Nuclear Maintenance Machinist for over 26 years, and there were just a few really high rad areas that no one went in. Other that that I have been in all areas. But back on topic.

The plant used a lot of different style bolt locking devices and all of them called for clean threads, lube and a torque. All primary systems called for a QC witness sign off on the procedure. To this day I use never seize on everything I work on like the lug nuts on my vehicles and never have any issues with bolting coming loose. Most of the plant piping just used flat washers and torque to spec.

One other thing, the grade of the bolts also determines the torque. If you take a grade 8 bolt and torque to a lower grade bolt spec, it will not get the proper torque to stretch the grade 8 bolt. And if you take a lower grade bolt and torque it to grade 8 bolting, you over stretch the bolt and thus risk weakening it.

Don

Sorry Don, That was a joke. Sector 7G is where Homer Simpson works at the nuclear power plant.

A slap on the wrist, Otto, for going off-topic.

Ron, I dismantled a '58 235 that did have the fiddly little lock plates on the flywheel bolts, but it also had a 6V flywheel on it, so someone had messed with it previously. The 1929-1957 parts manual shows the flywheel bolt lock plates listed for all 6 cylinders, so it appears that GM used them at least thru 1957 and I assume on into 58 and 59.

Thanks again, Jerry. I'll clean the threads, use red Loctite, and tighten to the max spec.

Just remember that red threadlocker needs heat for disassembly- - - - - -500 degrees or more to break the bond once it's cured. A minute or so with a Propane torch to the bolt head, and the bolts can be removed with relative ease the next time the flywheel needs to come off.
Jerry

Also, there are several different colors of lock tight, each have their own use for different applications.
Do your research, we seldom used lock tight on anything in a Nuke Power plant and never on safety related equipment!

Don

Bolts and external star washers. Little orange lock tight, not much, and correct torque.

https://www.ebay.com/itm/131074266087?_skw=chevy+flywheel+bolts&itmmeta=01KBTY5CHJ6YRRVZ89YBH2SCCF&hash=item1e84a293e7:g:Z4MAAMXQ0v1RZUgy

Thanks again, Jerry. I'll clean the threads, use red Loctite, and tighten to the max spec.

I torqued to specs and used blue locktite for vibration. About 3 years ago.
I recently removed the flywheel and had to use an impact wrench.

Heat is your friend when dealing with any flavor of Loctite- - - - -even the purple stuff that's used on tiny machine screws. When I'm working with rifle scopes and mounts, if I suspect they have been installed with Loctite, I heat the screw heads with an electric soldering iron before trying to remove them. There's nothing like twisting a screw off in a 75 year old rifle receiver to make the rest of one's day a real challenge! Ditto for buggering up a slot on a screw that costs $20.00 or more to replace! Threadlockers are "anaerobic adhesives" that cure in the absence of air. All of them have a critical temperature where they lose their locking ability. Heat also stretches a fastener and reduces the torque needed to turn it. Using Loctite on exhaust systems is just a waste of time, since those parts usually operate at temps that make the locking stuff useless.
Jerry

HRL, Thanks for the tip on using a soldering iron. Much cleaner in every respect than a torch or brute force. I had reused flywheel loc plates until there were no more fresh corners. When I looked for replacements I couldn't find any. So I used #2 permatex and external star washers. No leaks from the bolts visible on a clutch replacement but yes on leaks from the rear main seal. Sigh. Doesn't get into the clutch so I'll live with it.

It would take a huge soldering iron to heat flywheel bolts enough to break the bond on threadlocker. A torch is a necessary evil, but if the flame is adjusted properly the heat can be concentrated pretty accurately on the bolt head. The rifle scope screws I deal with are either #6 or #8, with very little metal mass around them. A flywheel will wick the heat away faster than a soldering iron can produce it.
Jerry