Page 1 of 1

1957 NH / Sludge Trap

Posted: Mon Feb 27, 2023 7:12 pm
by Julian Murphy
Going to remove and clean out at the next oil change = very soon.

L/H thread?
R/H thread?

Thread loc on re-assembly?

Or just tight?

How tight x ft/lbs?

Thanks.

Re: 1957 NH / Sludge Trap

Posted: Mon Feb 27, 2023 7:38 pm
by will_curry
It's an ordinary right-hand thread and can be very tight to shift.

Giving the head of the sludge trap a good thump is recommended
to help loosen the thread.

I put the bike on the stand and select top gear. With the sump plate off
and the spark plug out turn the back wheel slowly until the sludge trap
appears in the sump. Wedge the back brake on with a suitable block
of wood, put the socket on the trap and then put a bottle jack under
the socket head. On a bad day I've used a fork stanchion as an
extension but so far in over 50 years they've all come out.
sludge_trap_1.jpg
No loctite or anything else on reassembly and just use the standard
T bar to do it up 'reasonably' tightly. I've never had or even heard
of one coming out in service.

Re: 1957 NH / Sludge Trap

Posted: Mon Feb 27, 2023 8:48 pm
by paul.jameson
I do like the idea of the bottle jack under the socket, having never thought of it. But equally, in upwards of 50 years, all mine have come out too.

Re: 1957 NH / Sludge Trap

Posted: Mon Feb 27, 2023 10:06 pm
by JohnnyBeckett
hi i just use a very good fitting 6 sided socket and a powerbar and hold the socket up to the sludge trap with one hand and pull the powerbar with my other hand and they come out ok, just make sure the socket is the right size and a very good fit

Re: 1957 NH / Sludge Trap

Posted: Tue Feb 28, 2023 2:13 am
by nevhunter
Do things optimally BEFORE the HEX is rounded off. I've NEVER had to drill one out and never seen evidence of one coming out in service. Many are totally filled with tightly packed carbon and stuff and sometimes has to be drilled out of the hollow bolt and the oil drilling also to the timing side driveshaft. I've only found them this bad in old motors when I rebuild them. Many earlier motors didn't have a direct feed to the big end and just got it by "MIST" Nev