tony.barnett wrote: ↑Tue Apr 30, 2024 1:16 pm So, I have concluded the investigate by returning to the scene of the crime - I readjusted the valve lifter - hesitation gone. Just need to put the carburation back to where it was. Thanks to all that tried to help.

So, for the future time when I fall into this hole (!), I guess it was too tight?

Thanks Ralf and Simon, I will order a new needle jet and needle and give this a try - would prefer to keep the carb original if possible! Alistair There's a few details here showing the wear in the needle: https://ariel-square-four.blogspot.com/2021/03/wng-finally-fixed.html?m=0 I think the most in...

My 1958 350 NH is fitted with a standard 376 monobloc with a 200 main jet, 106 needle jet, 25 pilot jet and 3 1/2 cutaway slide, C needle. It is running very rich at low throttle settings, sooting up the plug and misfiring if ridden in slow moving traffic.This is despite the throttle needle being s...

How does the throttle slide feel if you push and pull it through the bell mouth? Any fore & aft movement? Secondly, and not wishing to hijack your thread but my 1930 A also has a KC1. There's nothing mentioned in the despatch record; is it possible Ariel used BTH for a while during 1930 or are t...

Try here:

https://amalcarb.co.uk/carbspec/carbure ... es/id/4582

Looks like 106 needle jet, 15 needle jet.

Hi Barrie,

I've just seen the video you pm'd to me. Are they as noisy with the outer bearing fitted?

Perhaps post the video and see what others think?

Those OPRV's can be problematic at the best of times, in my experience, but the ball finding its way into the oil gallery must be the fault of the previous person who worked on the engine, surely? Has the inner end of the OPRV body been drilled-out at some time, I wonder? Allan. Maybe someone resea...

Mine came from singles spares, but obviously there's a problem with that at the moment.

Here's an example!

When I rebuilt the W/NG a couple of years ago, I had a similar problem. The crankshaft pinion was very worn; the cam pinion was fine.