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1961 ATCO Petrol 17inch Machine Reference 1761/2/3

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Arthur Sat, 03/12/2016

I require the locking nut for the crankshaft/flywheel fan shaft. It has never been removed until now and would appear to have been cross threaded on factory assembly, the thread is ruined following removal, so I have been informed by my friend a retired Leyland Motors toolmaker. The power pack I think is Suffolk and the nut is left hand thread 3/8" UNF ( Possibly )
I am not sure that the power pack is actually Suffolk. My late father whose machine it was until 1972 had written on the 1961 parts list I still have “ Suffolk Engine” .Although he was an Engineer there is no identification on the engine to indicate this.
What I am seeking is identification of the locking nut – size, type, and thread and were I could possibly obtain a replacement.
Best Wishes and Regards
A F Hall
afhall@lineone.net

Forums

wristpin Sat, 03/12/2016

If the machine has the original Suffolk Iron Foundry engine  your friend is correct in his identification of the crankshaft thread.  I have to say that I've never come across one with a cross threaded nut from new but plenty with damaged threads as a result on incorrect removal attempts. 

Hopefully it's only the nut that is damaged as they are available on that well known auction site . Suitable 3/8 24 tpi  left hand thread taps and dies are available by mail order  from Tracy Tools in Plymouth .

hortimech Sat, 03/12/2016

A picture might help here, You say it is an Atco made in 1961 and is fitted with a Suffolk engine, it may be a Suffolk, but there is a problem. Qualcast bought Atco in 1965 and before that, to the best of my knowledge, Atco didn't use the Suffolk engine.

sir_chook Mon, 05/12/2016

Hi All,

Atco certainly used Suffolk engines prior to 1965. I have one brochure that indicates that they were being used in 1962/63 for the 14" - 20" domestic mowers. However, prior to this it appears that the mowers were still powered by Villiers engines. 

Cheers,

Sir Chook

wristpin Mon, 05/12/2016

I think that regardless of the supposed date of manufacture and whether or not it is the original engine,  the deciding factor as to what engine is fitted to the machine in question is how the flywheel is retained  - SIF , 3/8 left hand threaded nut : Villiers for stroke the Villiers self extracting system.

The shame is that the whole thing could have been cleared up from the word GO if only people would post images - it's not that difficult!