Pan Cylinder nut lock washer

[davidsonp9]

Was there any time that cylinder nut lock washers were not used. I know that they are not used on SV motors. I have a pan motor that does not have lock washers.

[bmh]

Far as I know they always used a lockwasher on the cylinder studs of OHV models. Till the late 70's anyway, when they started using that triangular thing.

[Chris Haynes]

Actually Panheads used a thick flatwasher, not a lockwasher. Part number is 6469 which is a 7/16x3/4x1/8" plain steel washer.

[davidsonp9]

Thanks Chris. Since it is only a flat washer is there any concern if no washer is used?

[Chris Haynes]

The thick washer is critical. Spreads the force. The bolt may be too long without it.

[davidsonp9]

Chris, I believe the flat washer 6469 is for the head bolts. I am interested in the cylinder base studs. or does the cylinder base use the same flat washers on the Pan?

[Chris Haynes]

Oops. I misread your question. The base nuts did use a lockwasher. Page six of the 1957 oarts catalogue shows part number 7055. A 9/16x11/16x1/6".

[Rubone]

Chris is giving the information for a headbolt! I believe you were asking about base studs. The base studs use a LOCKWASHER part # 0265 (old #) or # 7055 (new #). It is described as 7/16 x 11/16 x 1/16 thick. However, in practice lots of original engines I have seen do not have lock washers on them, just the base nut. My own '42 FL that is an all original engine has no washers. Palmer references washers on BigTwins only. Some factory photos show base nuts with no washers. I don't know what is absolute or not. Anyone have a definite answer! More factory photos Chris?
Robbie

[davidsonp9]

Thanks RUB. Your statement is exactly why I ask. I have seen many "Factory" or "Restoration" photos that do not have washers but all parts lists I have seen call for them. I guess it can't hurt to have them but since the motor is together I would rather not remove the nuts unless most of you feel it is a must to have them.

[Rooster]

I see washers on the base nuts in these factory photos of a '52FL.

[Chris Haynes]

This 1950 factory photo shows parkerized lock washers under the base nuts.

[LCC]

Pan cylinder nut lock washer

An experienced shop in VT. does not use them with the reason being lock washers are subject to breaking and that would be a critical place to have that occur. I have a 48 FL motor with 25000 miles done 20 years ago by them this way with no issues Larry

[Robert Luland]

The pans always had the lock washer. Now there are a couple of other things that cropped up out of Tom's photos. From what I can see the cylinder base nuts seems to be cad but should be park like the washer as far as I know. I've had this argument here before that factory photos were dressed up to look pretty. If I owned a manufacturing company. I would show my best side first. Now I saved the best for last. Study the hold down bolt head on the circuit breaker. I see people all the time looking for the dome head. Well acording to Chaed at Old Dude this is wrong. Acording to him what would happen was that the hole would fill up with crap and people would go to the next shorter bolt which was the dome head. Tom's second photo proves he's right. That a flat head standard bolt. Bob L

[Rooster]

For the record, the photos I posted are some copies that I got from Chris Haynes, and they are 1952 factory photos from his excellent collection. Thanks again, Chris, I use them often!

[bmh]

Robert, Gotta disagree with the parkerized base nuts. Knuckles used parkerized base nuts as well as most 48's I believe. But after 49 the nuts were cadmium while the washers remained parkerized. The following photos are of a mid year 49. This is one of the only original old bikes I have seen that I don't believe has ever been apart, it's only got 10,000 miles on the clock. It is also one of the few that did not receive spring cleaning via a can of aluminum paint. You can still clearly see remnants of the cadmium plate on the nuts as well as the parkerized washers.