Dropped the float needle on my P218.....

[Damien Walker 289]

I needed to sort a running problem with my 518H last week and so took the top off the carb and removed the floats.....clatter, something fell off! When I looked, there was no needle valve any more. I searched everywhere for it and concluded that it must have dropped down the air intake into the engine. 

 

Ok, so the first thing to do is to NOT rotate the engine.....with luck it will still be in the inlet tract and not in a cylinder.

 

Second thing is to remove the carb. Ha! can't do that, it's bolted through the manifold from underneath, so the manifold has to come off. 

 

Double Ha! Can't remove the inlet manifold with the exhaust manifold in place 

 

Guess what?: The exhaust manifold is seized into the head and will not budge.

 

I took the angle grinder to one exhaust pipe with the view to twisting the other pipe to encourage it to loosen but that's actually not possible with all the other bracketry etc holding the exhaust in place. 

 

However, the cut front pipe was not seized and was easily removed which allowed me to remove the inlet manifold bolts on that side, and with the other two bolts loose too, I managed to tilt the inlet manifold sufficiently to enable me to remove the other two bolts and pull it from underneath the exhaust.

 

Nothing fell out of the inlet manifold and clearly there was nothing in the valve chambers on either cylinder (both inlet valves were closed) so the needle valve must have dropped clear.....ie this whole enterprise was a complete waste of time! 

 

I shot blasted the manifold because it was in a bit of a state and spray laquered it (powder coat would have been better but I don't have any 'clear') and discovered that some of the gasket between the two halves of the manifold was missing. I think this is a known source of running problems on these engines, so I sealed it with silicone. May be the whole enterprise was NOT a complete waste of time after all! 

 

Everything was reassembled (new needle valve obtained) and I repaired the now slit front exhaust pipe with a thin tube of shim material and a wide hose clamp...which looks reasonable and seals well.

 

The original needle valve is now suspected lost forever!

 

The moral to this story is simply to stuff a rag into the air intake to stop anything from dropping in. The needle valve is hooked on the operating lever on the float assembly and is not retained by anything. When you remove the float assembly, the needle valve comes with it and just drops off when it pleases!

[Chaz54 79]

Yep, been there, done that!

[adsm08 3,136]

Powder coating is a really fancy way to make crumbly pieces of rusty metal.

[Damien Walker 289]

42 minutes ago, Chaz54 said:

Yep, been there, done that!

Ah. but did you find the missing needle? Where did it go please, I need to know!

[Damien Walker 289]

40 minutes ago, adsm08 said:

Powder coating is a really fancy way to make crumbly pieces of rusty metal.

I have some sympathy with your opinion as it seems that many organisations use powder coat as a quick way to achieve a hard glossy finish without doing the proper preparation. The result is that the coating delaminates, water gets underneath and yes, before you know it, your beautiful item is converted into ferric oxide, still with the hard shell of powder coat holding the bits together (and not very well!).

 

However, if the base metal is shot blasted and a zinc based primer coat is applied first, then you get a really robust finish.  It's wise to keep all such painted items indoors too....but I powder coat everything Wheelhorse etc these days whenever I can....always with primer and I always keep them under cover. So far, there has been zero deterioration on my 518H and that was done a couple of years back now I think and being left overnight on a trailer in the rain a couple of times when I was away from base. Powder coat is thicker and tougher than any wet paint I know and I would encourage you to try it sometime. Ok so you need an electrostatic gun to apply it (mine was cheap from a famous online auction house)  and I use a domestic oven to 'cure' the powder. Ok, so I can't do a Wheelhorse bonnet, but I can do wheel rims. It is also fairly idiot proof too, requiring almost no skill at all to achieve a very good finish. You can go from an unfinished part to completely finished in say 30mins to shot blast, 10mins to set up and spray and 15mins to cure in the oven. Obviously it has to cool down too and you need to do it twice for the two paint layers, but you can complete your item in less than two hours....no curing time, no sanding, no polishing required.

 

A couple of weeks back I built an outdoor dog run, using commercially sourced steel posts and netting, all of which is powder coated. The netting has been used all over the UK for surrounding our schools since we had an appalling shooting incident (tennis star Andy Murray was at the school but not involved if I recall correctly) and lasts very well indeed. I have built the gate using steel tube and weld mesh and I had it professionally coated (too big for my oven) and it will be interesting to see how well it all lasts. Most important to me will be which part rusts first, will it be the commercially sourced fence or my 'properly' powder coated gate? If anyone interested reads this in the future and wants to know how the trial is running, I'll be very happy to report back!

[8ntruck 7,771]

My dad was in the Army Air Force during WW2, working as a weight & balance officer in North Africa.  I think he might have been a little board, as I saw that he was taking aircraft engine training when we found his military records after he had passed.  This made sense out one of the stories that he told me.

 

He described how he and a few others were reassembling a radial air raft engine, when one of the other guys dropped a nut - right down the carb!  He said they all kind of sighed, then started disassembling the intake system until they found the dropped nut.

[JoeM 8,275]

I like to close the throttle (if I can remember to do it before I take those apart). 

Just a couple weeks ago had a bud drop one down under the shroud. what a pain to get it out. 

[Damien Walker 289]

20 minutes ago, JoeM said:

I like to close the throttle (if I can remember to do it before I take those apart). 

Just a couple weeks ago had a bud drop one down under the shroud. what a pain to get it out. 

Oh I thought about that AFTER I had dropped it!

[Bill D 2,246]

There is a Taryl video where he give a Briggs part # for a new needle.  The Briggs Vanguard and Onan both use Nikki carbs.

[lynnmor 7,787]

21 hours ago, Bill D said:

There is a Taryl video where he give a Briggs part # for a new needle.  The Briggs Vanguard and Onan both use Nikki carbs.

video   

Briggs 797410 needle valve

[Handy Don 13,966]

On 6/1/2025 at 10:51 PM, 8ntruck said:

He described how he and a few others were reassembling a radial air raft engine, when one of the other guys dropped a nut - right down the carb!  He said they all kind of sighed, then started disassembling the intake system until they found the dropped nut.

My youngest brother (about 8 or 9 at the time) dropped an aluminum nut down the hollow S/G mount of my ’66 VW as I was just finishing up a bunch of remedial work. He was trying to be helpful, of course, so I refrained from inflicting any bodily or emotional harm--just. Several unplanned and frustrating hours of work ensued (including slow hand cranking the engine) and I finally found it about to enter the meshed-gear oil pump which had no screen to prevent stuff from being sucked in!