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MG TD TF 1500 - Lockwire - flywheel

Will someone please post a photo of the original lockwire configuration on the bolts that attach the flywheel to the crank?

I didn't photograph mine when I removed the clutch disk and pressure plate to replace them. A club member is replacing the clutch disk and pressure plate in his TD. The lockwire has been removed.

I am helping him. A photo should be enough, but your experience will help. Any suggestions for getting tight, balanced lockwire through the four bolts? What gauge of stainless lockwire? I'll be using my "precision" Harbor Freight lockwire pliers.

Thanks

Lonnie
TF7211
LM Cook

Lonnie, I just reactivated a thread that should answer your questions. Bud
Bud Krueger

Thanks for reviving the thread, Bud

I believe that the lockwire on my flywheel was all done with one wire. It didn't have many twists. Don't know if it was original. I don't know if I'm good enough to properly lock four bolts together. Looks like locking two bolts, then the other two will be easier and better balanced.

Thanks

Lonnie
TF7211
LM Cook

I don't know if it's the 'original lockwire configuration, but this is how I did it.

I also believe that properly torqued bolts don't need any lock wires?

Willem van der Veer

Willem-
While your safety wire job is technically correct as far as the wire's route, it is not very robust having a single wire wound around. Enclosed in the pic shows a wrong, but good example of two bolts tied together in the British style of safety wire. The bolt to the left should have the wire going around the head to the top, not the bottom. As it is now in the pic, if either bolt loosened, it would allow the other to also loosen--wrong. Safety wire pliers are a big help twisting the wire. In this example, the process was started correctly by taking about half the length of wire and inserting it into the big bolt in the left hole and out the upper right hole, then wrapped down clockwise to meet up with the original ingoing wire. Then the twisting. Err on the side of not twisting enough to check how it will fit into the other bolt, and twist a little more length until it is just the right amount to go into... you should see what I mean. There is really no need to combine the wire on all four bolts. Two and two works just fine.

Trust me, properly torqued bolts do come loose. Especially on a flywheel that may never see the light of day for, who knows how long?

Pic borrowed from thejalopyjournal.com "how to safety wire"

D mckellar

See this link for some other examples, as well as more critique on the pictured job: http://www.jalopyjournal.com/forum/threads/tech-how-to-safety-wire.215935/
D mckellar

A good source of information on the subject of lock wire is a YouTube clip under the title of Jet tech: lockwire. The guy doing it is a Canadian working in the aviation industry on jet engines.

My father worked on aero engines for the RAAf & RAF in WW2 and I remember him telling me that if you didn't wire bolts correctly, or missed any that should be done, you were up on a charge. I think these guys know their stuff.

Michael
M R Calvert

D mckellar.
I am surprised that photo has not been commented on.
It would never pass any inspection as not one but both bolts are wired using the incorrect postioned holes. The left one is actual;ly wired backwards while the other one on the right is one hole out.
Sandy
Sandy

Michael -

Yes - the "Jet Tech" guy has a wonderful video on how to lockwire. I followed it, plus a few links because I had to learn how to lockwire when I rebuilt my gearbox.

Here are the links:

> Overview (view first to learn basics)
http://www.youtube.com/watch?v=IwkL0qfyFL0

> "Jet Tech" detailed instructions (view second to see expert methods)
http://www.youtube.com/watch?v=OwFjUX6SaY8

> Verbal description
http://ultralightnews.com/pilotslounge/safetywire.htm

> Verbal descriptions and diagrams
http://www.eci.aero/pdf/10-3.pdf

Lonnie
TF7211
LM Cook

I absolutely agree with Sandy. The position of the wire in relation to the direction of rotation to undo the bolt, and the rotational force the wire exerts to counter that movement is critical.

The YouTube clip referred to above makes this very clear. Much better than I can express it.

Happy lock-wiring!

Michael
M R Calvert

D Mckellar,

Thanks for your comment, attached is a picture of my main bearing wiring job. Better?

Willem van der Veer

Willem could the interconnecting wire ride up the shoulder of the main bearing cap? If so then it seems there is nothing to prevent either nut from loosening. When lockwiring aviation components together years ago in the RAAF my instructor insisted we always ensure that the interconnecting wire was taut. This is just as critical as getting the direction of the wire correct. Cheers
Peter TD 5801
P Hehir

William.
In that situation I would have used a cotter pin on each nut. There does not appear a way to keep the interconnecting wire taunt.
SANDY
Sandy

And Willem...recommend you shorten your rear main drain tube to keep it out of the oil in the sump. The TABC group has found that shortening it reduces oil leakage from the rear main.

Gene
Gene Gillam

The problem with a Cotter key in this case is it would still allow the studs to blackout. All a Cotter key would do is keep the nut with the stud in the bottom of the sump. Regards, tom
tm peterson

Peter, although it is hard to see on the picture the wire is taut with nowhere to go.
Willem van der Veer

Tom, you make a very interesting point. The offering by the parts suppliers of Nyloc nuts as a modern alternative to castle nuts on main bearing caps and some other locations could possibly be giving a false sense of security. A drilled stud could of course still be lock-wired provided the hole was not covered by the Nyloc nut. It would be good to have some further expert input on this subject.

For any people like myself who are building an engine and enjoy some of the background theoretical stuff an interesting article about reuse of bolts and studs in critical locations can be found at: http://www.engineaustralia.com.au/~engine/sites/default/files/SB004.pdf

Michael
M R Calvert

Another thing to remember when talking about aircraft versus auto safety wiring is that auto's generally only have one hole drilled through the head of the bolt. The jalopy journal example I choose because the correctly done big bolt head is only correct when you know that. It is straight in line with the connecting bolt, so it is an example showing the worst possible place for the head to end up when properly torqued. It will work, though, as long as the twists and connections are tight; which the example is not. Of course another hole could be drilled, but that is just not how auto safety wiring is generally done.

An FAA source, Check out chapter 7, page 19 (not subsection 19, you have to go down a good ways to get to page 19)in this FAA publication on safety wiring. You will note that not every bolt appears wired in the locking only mode, but they are considered all locked.
http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/99C827DB9BAAC81B86256B4500596C4E?OpenDocument

As wrench for a small racing team, I have not been using nylocks in key areas on a variety of British Sports Racers for over 35 years. A Lotus Fifteen we ran for 20+ years quickly found split lock washers on one side of a propeller (half shaft) shaft, for instance, as nothing else worked short of locktite, left handed fasteners, or drilling holes and safety wiring.
D mckellar

Gene, the pipe is shortened as you can see by the neat chamfered cut on it (for about an inch if memory serves me right).

The original is much longer, as you can see on the attached picture. The shortening is to (allegedly) stop siphoning action from the sump, so the pipe only has to be shortened enough not to hang into the oil?

Willem van der Veer

This thread was discussed between 02/11/2015 and 05/11/2015

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