I would like to clean out as best as possible the insides of my peashooters.
I have heard that "caustic soda" is very effective.
Can anyone confirm this, what it is, where to get it, or any other good de carbonizing muffler ideas?
Thanks in advance

highdesert wrote:I have heard that "caustic soda" is very effective ... what it is, where to get it

It's Sodium Hydroxide. You could buy it at a chemical supply house, or an oilfield mud-supply store, but the easiest source for a small quantitiy is Drano crystals, which is about 60% NaOH. It's nasty stuff, though. It will burn your skin and it will blind you if you get it in your eyes, so proper protective gear is required, including effective eye protection, i.e. NOT some cheesey Home-Depot safety glasses, but a full face-shield and goggles.

Depending whether you're in the UK or the US, caustic soda (UK) or lye (US) is the best way of cleaning out the mufflers.

When I lived in the UK, I used to run an Ariel Leader. It was a 250cc parallel twin two-stroke. The factory recommendation was a oil/gas mix of 16:1 - a pint in every gallon. It smoked like a factory chimney, particularly at full throttle, which it was often at!

The mufflers were a perennial problem. They'd get clogged up with oil residue about every 8 weeks. I got fed up of taking them apart to clean all the baffles, etc., so I contacted Ariel's customer support to see if there was anything insiide the muffler that was aluminium. This is critical, because lye will dissolve it. They said "nothing in there is aluminium".

My procedure was to jam a raw potato in the engine end of the muffler, stand it upright in a corner of the garage and pour a hot lye soluion into it until it was full. I can't remember what proportion lye to water, but I'm sure one of the old shade-tree mechanics in the forum can tell us!. Let it sit for an hour or so, then pour off the lye solution and rinse thoroughly with lots of clean water. Give them time to dry internally (or warm them up with a heat gun) then re-install.

Interestingly, Ariel said "Oh, by the way, we,ve found the engine is quite happy with a 32:1 gas/oil mix and if you use Bardahl, you can go to 40:1. That sure cut down on the smoke. After using Bardahl for a while, I was quite surprised to find, on emigration to Seattle, that it was a local product here. Oly Bardahl used to sponsor an unlimited hydroplane boat (powered by a Rolls-Royce Merlin engine) in the national race series, which originated in Seattle.

Oly Bardahl used to sponsor an unlimited hydroplane boat (powered by a Rolls-Royce Merlin engine) in the national race series, which originated in Seattle.

Hi Frank,

I remember Miss Bardahl. I lived in Shorewood from 1959 to 1966 and could hear the Sea Fair Trophy races from 10 miles away. Ron Musson, Bill Muncie...Bardahl, Wahoo, Thriftway (aka Miss Century 21 after the Seattle Worlds Fair). Wahoo lost a rudder and went through a Coast Gaurd boat. When the hydroplanes sank it was a mad scramble to recover the engine...they didn't care about the hull.

Yup,

I remember Miss Bardahl too. We used to stand mufflers with solvent in them and then run the steam cleaner through. Never tried an acid.

I learnt that soaking spark plugs in white vinegar dissolves carbon, so gave it a go in the pea shooters. Blocked them off, filled then up with cheap white vinegar from the supermarket, left it for a couple of days, emptied it and gave it a high pressure squirt with the garden hose. All the carbon flaked off.

I will try the white vinegar, thanks!