Cylinder Base Locks on Fiftys Fl Models

[partshunt]

Hi there all panhead guys:- On a fiftys Fl engine, the parts books shows in the cartoon that the 7055 lock washer goes under the 1/2" deep cylinder base nuts. Yet when you look up the lockwasher in the text of a 57 parts book, it shows no lock washer is used under the cylinder base nut. I ask because it you instrall a 7055 lockwasher the nut will extend above the 16831-30 stud about 1/16 " or more. The # 16831-30 stud listed is not long enough for lockwashers. Were these cylinder base nuts originally instakked with no locks?...Thanks...Joe.

[steve_wood]

I use the lock nuts on my 56FLH. The studs have plenty of thread allowing them to be adjusted outwards to allow space for the lock nuts.

Keep in mind that the nuts are only torqued to something like 28 ft-lbs. And they undergo significant vibration. Not using lock nuts might be asking for trouble.

steve

[john HD]

partshunt,

i have them on my '55. i was provided these photos by chris H and it shows them in '55 from the factory.

john

[Panacea]

Steve-wood, I thought base nuts were supposed to be torqued to 35-40 ft lbs. Where did you find 28? Mike

[steve_wood]

I could be wrong... just going on memory. I seem to recall that it was a fairly low value. 35 - 40 is probably right.

steve

[partshunt]

Thanks for the pics John, they tell the story and also thank you to all with your prompt and usefull replies...Joe

[Cotten]

I'll endorse 40 ft/lbs with proper technique and the proper wrench and adapters.
If torque-plates are used for fitting the pistons, the same spec should be used for both honing and installation.

(There should be plenty of discussions in the Knowledge Base..)

Note in the pictures that the nuts are cadmium, and the locks are parkerized!

....Cotten