Optimus 99 ticking

Hi all,

My brother commented that he liked my Optimus 99 so I decided to find one to give him for his birthday later in the year.

The one I picked was pretty filthy but seems in decent shape overall.
I’ve cleaned it up, replaced the seal on the tank cap and reset the cleaning needle (the pencil eraser method with 4 clicks). I also removed the old fuel and filled up with Aspen 4.

It fires up pretty nicely with good heat (enough to blue the pot rests) and turns off as it should. The only thing is it has a persistent ticking. I initially thought it was heat expansion but it doesn’t go away and varies with how open the valve is (more power faster ticks).

Has anyone else experienced this?
Could it be fuel supply or a worn jet?

I love these old stoves but I’m by no means an expert. I have a couple of other 99’s (a flat based version and a later example) and neither of them display this quirk.

The stove is running ok but I just wanted to check in with those with more experience than me.

first couple of images are from the seller I bought it from. The second couple are it running with me

 

Ticking? A distinctive tick/click-like sound?
Could you take a video of it running please

The 99/8R/123R etc etc with this style/family of burner style do have a distinctive buzz/flutter/raspberry sound when they are running flat out as you'll know with your other one, is it a very different sound to this?

Alec.

 

@optiben80 - Have you opened up the SRV to inspect the condition of the pip and spring?

Pharael.

 

Thanks Alec,

It’s very different to the distinctive flutter, ram-jet sound of my other 99’s (I also have a few 80’s an 8 and a Primus 71 so that sound is music to my ears!).

it’s much more like a tick tick tick noise, very much like metal expanding in heat. However I’m fairly confident that isn’t the case as it continues once everything is heated up and it directly correlates to how open the valve is.

I thought fur a moment it could be inconsistent fuel flow but whatever the sound is doesn’t seen to affect the level of the flame.

I’ll try to take a video tomorrow

 

I haven’t yet,

Could this cause such an issue? The stove seems to pressurise ok?

I have a refurbished cap on one of my 80s which I can test on the 99 tomorrow .

 

Yes, one of my old 8’s did that, finally fixed it I think, but can’t recall what it was.
Duane

 

@optiben80 - another thing you could try is running the stove without the cleaning needle. Process of elimination so to speak.

Pharael.