mk1-forum.net

Do people still use the tab locks on the diff bolts holding the crown wheel on......

I toss them and, use loctite......

Any thoughts, reasons for or against etc.....

The last ones I bought were soft, you could see them oozing out from under the bolt heads. All locktabs I've found the same, at least a few years back.

I've been using Loctite 243 on all these, the Damper Bolt, Cam Nut, etc - no issues and no intention to change. The key with any of these products is to get everything super clean before applying.

Please don't use loctite in engines & gearboxes. It is unnecessary and often a pain in the arse to get the bolt undone again when some poor mechanic has to fix something on your car.
I use the locktabs on the diff bolts. I am.yet to have an issue with "soft" locktabs.

Drill and lockwire.

850man wrote: ↑Sun May 23, 2021 4:10 am Please don't use loctite in engines & gearboxes. It is unnecessary and often a pain in the arse to get the bolt undone again when some poor mechanic has to fix something on your car.
I use the locktabs on the diff bolts. I am.yet to have an issue with "soft" locktabs.

Agreed, use what the manufacturer intended and you can't go wrong. Appreciate that some new lock tabs aren't that good, but NOS ones are still quite easily available.

As for Loctite .. a certain gearbox god uses it on the 3rd motion shaft nut rather than a lock tab. I had the unfortunate job of removing it to sort the gearbox problems out .. what an absolute bastard it was. Ended having to warm up the Loctite to get the nut off and subsequently f***ed up a brand new double bearing

As Spider Chris alludes to, there are several types of the generic 'loctite'. And some are designed to cater for JUST the application we're talking about. The trouble is that the first thing we think about when we hear the word is '....what a bastard that is going to be.....' Just read the loktite data sheet (it's in the info part of the forum) and use the right sort. One in particular - forget all the numbers - eases off with just a quick blast of heat but will tighten up. So another blast and it's free!

I wonder how many gearbox builders or just enthusiastic amateurs have one single bottle or tube of loctite and use it for everything........

Or as I do, use loktite with the lock tab...., the tab acting as a washer and secondary locking medium. In the world of armour we used to use it as our friend and not a necessary evil

Andrew1967 wrote: ↑Sun May 23, 2021 10:12 am As for Loctite .. a certain gearbox god uses it on the 3rd motion shaft nut rather than a lock tab. I had the unfortunate job of removing it to sort the gearbox problems out .. what an absolute bastard it was. Ended having to warm up the Loctite to get the nut off and subsequently f***ed up a brand new double bearing

I have previously modified (shortened) the nut and used a first motion nut (IIRC) as a lock nut. Worked brilliantly.

As Peter touched on, there's a few different grades of locking compounds, most can be dismantled with normal tools, some are permanent, needing heat to release them. Like anything, use the right one for the application. I can't say I've ever had trouble disassembling anything I've assembled with loctite. I have however, found many many loose Flywheels and Harmonic Dampers over the years, that had been untouched since leaving the factory with locktabs.

Perhaps not a fair comparison here, but locktabs were dropped from mainstream production in the 60's and 70's by many other manufacturers and many took up with locking compounds, most being pre-applied to the new fasteners when purchased.

I basically use the lock-tabs for decorative purposes only. Loctite 243 (mid) will prevent loss of clamping torque. I avoid Loctite 277- as it requires loads of heat to enable disassembly.

Split washers, lock-tabs and serrated washers are not used any more for a reason - namely cause they don't work.
Only ones working:
Spring washer (needs very precisely applied correct tightening torque)
NordLockwashers.

MiNiKiN wrote: ↑Mon May 24, 2021 8:46 am I basically use the lock-tabs for decorative purposes only. Loctite 243 (mid) will prevent loss of clamping torque. I avoid Loctite 277- as it requires loads of heat to enable disassembly.

Split washers, lock-tabs and serrated washers are not used any more for a reason - namely cause they don't work.
Only ones working:
Spring washer (needs very precisely applied correct tightening torque)
NordLockwashers.

Schnorr washers are very good. Their only downside is you have to use the nearest metric equivalent on imperial fasteners.

If you must use additional locking these are used inside gas turbine combustion chambers Nord-Lock washers https://www.nord-lock.com/shop/buy-here ... Buy%20Here available in imperial sizes.
But I would also like to add that in the late 60's early 70's GEC / Paxman (diesels) deleted all the castellated nuts, and split pins from the bottom end bolts of their high speed diesel's, indicating that if the fastener is properly tightened it should not come loose, they reviewed the tightening procedure, did away with the torque settings, and used bolt elongation measurements instead.

GraemeC wrote: ↑Mon May 24, 2021 9:32 am

MiNiKiN wrote: ↑Mon May 24, 2021 8:46 am I basically use the lock-tabs for decorative purposes only. Loctite 243 (mid) will prevent loss of clamping torque. I avoid Loctite 277- as it requires loads of heat to enable disassembly.

Split washers, lock-tabs and serrated washers are not used any more for a reason - namely cause they don't work.
Only ones working:
Spring washer (needs very precisely applied correct tightening torque)
NordLockwashers.

Schnorr washers are very good. Their only downside is you have to use the nearest metric equivalent on imperial fasteners.

With "Spring washers", I actually meant them Schnorr washers - but their name didn't come to my mind.