68 Commando Crankshaft bolt spanner size

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Hey everyone just a quick question what size spanners are right for the Commando Crankshaft through bolt nuts my Whit ones don't fit guessing they are af or british cycle?

Also who's oil cans are everyone using to prime the crank with oil.
Thanks in advance.
 
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The early bolts and nuts I believe are 1/4 Whitworth hexagon size (as Mick Hemmings states in his engine rebuild video)?
 
Hmm wonder if its had different bolts an nuts put in at some point the ones that came were 1/2" AF af as well. The Cranks definitely been apart at some point as someone's marked up the halves. Got a pair of AF 1/2" spanners on the way tomorrow :)

Just gotta sort a good oil gun out now for priming the crank.
 
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What's the hurry as priming the crank is usually done after the engine has been rebuilt.

68 Commando Crankshaft bolt spanner size
 
Got a pair of AF 1/2" spanners on the way tomorrow :)

With a Commando in the shed already and (hopefully) a late 60s Triumph joining it in the not too distant future, you need to invest in a pair of unified spanner complete sets...!

Late 60s Brits can be a horrid mixture of fasteners. Hence so many get mullered !!
 
Thanks guys

Ahh I was miss understanding the NV 68 manual I was reading it just had text stating something like remember to prime the crankshaft using a wiseco oil pump. That clears it up in my head thanks LAB.

yep hoping to get a full set ordered Eddie wanna invest next year in some high quality whit an af spanners when funds allow as you say once the remaining Japanese bikes lc250 an my gsx750et are sold it'l be mainly British stuff :)

Guessing there's no torque an its just tight then peen the ends? + the tabs on the two back bolts.
 
Ahh I was miss understanding the NV 68 manual I was reading it just had text stating something like remember to prime the crankshaft using a wiseco oil pump.

With the engine in the frame, oil feed line connected and oil in the tank, it will probably 'self-prime' in a few hours anyway.
 
I guess this may help:
Tourqe is 25 foot pounds as stated here:
NOC Conrods Conudrum

To my knowledge early Commandos ( mine is a 1970) have Withworth size nuts and bolts around the engine .
The rest is AF size .
When I got my Commando is was proud having an ex-US Army AF spanner set but had to invest in a Whitworth spanner and socket set.
You need good fitting spanners when you torque down the head, barrels etc.
 
Sorted 1/2" found my vernier incase anyone else wonders. Guessing there's no torque setting on them all after flicking through the manual?
Hi Norton Rider,
1/4 inch Whitworth is 0.525 inch. How accurate was your caliper measurement? Are your Whitworth wrenches too small?
Ed
 
Guessing there's no torque an its just tight then peen the ends? + the tabs on the two back bolts.

Bad guess


Crankshaft stud nuts (12 nuts) 30 ft lb.

But that may be wrong for the earlier mix of 5/16 and 3/8 studs plus will be different between Cycle threads and UNF threads.

Also do not use the Haynes manual figures, they are definitely wrong.

RGM have the following

3/8“ Crankshaft studs (Mk3 Commando) 30 lbs/ft
5/16” Crankshaft studs or bolts (all pre MK3 twins) 20 lbs/ft
 
Hey everyone just a quick question what size spanners are right for the Commando Crankshaft through bolt nuts my Whit ones don't fit guessing they are af or british cycle?

Also who's oil cans are everyone using to prime the crank with oil.
Thanks in advance.


Just in case it doesn't say in the manual you are using....it is easy to slip when tightening these crank bolts, particularly with open ended spanners.

If you can get a combination spanner of the right size you may have to grind it down to allow it to slide over the nuts far enough to get a proper fit with the spanner fully over the nut faces.

Whatever you use, put some protective tape over the big end journals to make sure that, if you do slip, you don't damage the ground surface. Several layers of electrical tape should do it.

Leave the tape on until you are ready to install the con rods.

Achieving the torque setting is possible if you play with tools. Some of our friends on here are religious about torque settings, some of aren't using them where access is available to the torque wrench.

Personally I have a couple of dedicated combination spanners which I have ground for fit, cut off the open ends and extended to a total of less than 12" and just do them up tight, and even.

I use loctite and don't peen!

I discussed the process with Steve Maney since I have one of his cranks, he pretty much concurred but said 'just make sure those spanner extensions aren't too long!'
 
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Yep 1/4 inch whit was sloppy on them. Usually a really tight fitting spanner on my 650ss on 1/4 inch nuts.

Thanks Commando it didnt mention them in my NV manual which is for the 68. That's a big help.

Yep ordered combination ones must admit they did look like a recipe for slipping with an open end spanner not got a vice let alone a soft jaw one so I'll get dad to hold the crank steady so there are no accidents :)

Got some 6" length combination spanners an Ill see if I can get a torque wrench in access wise tomorrow when I get it done.

What loctite did you settle on Steve? Know there's a few different numbers of the stuff. I'd love to get some Steve Maney stuff in a Norton one day.

Thanks again everyone proving access norton is invaluable as ever.
 
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