Hi Guys,
More of 'The devil makes work for idle hands'.....
I haven't been too happy with the cc breather valve of late, possibly its my imagination, but I have seen a few minor oil seeps here and there since I cooked the big end bushing... Maybe they were there before, or maybe I am getting tired of shining the paintwork, but it pretty much boils down to me actually having a fun time trying to top off the oil every now and then... Since the starter motor was installed, the geography between engine and gen head has become a little over populated... The previous breather and extension tube was probably working OK, but it was a little short and just a tad small in diameter for easy pouring into... As usual, the old saying, 'go big or don't go' kicked in and I quickly knocked this filler/breather up out of some bitso shitso I had lying around... it is all pretty much repurposed, so don't laugh too loudly (I have sensitive hearing and can hear across oceans) .... The upright is 1.5" gate pipe, the valve is an old 1.5" non return valve with the spring return removed, the cover is an old brass basin outlet that has been looking for a useful purpose in life since retirement....
http://www.warriorpaintball.co.za/private/TM1 CC Breather Mk2 20160205Interestingly, the pipe length, coupled with the weight of the stopper in the valve, coupled with the resilience of the valve seat, coupled with the pipe diameter, coupled with the phase of the moon,Venus and the sun, added up to spot on the resonant frequency of the whole shebang... It is the first time I have heard an engine run with the breather pipe resonating and making more noise than the whole rest of the engine, exhaust included.... To stop this resonance, I first added a spring back into the valve, to no avail... I then threaded the guide on the valve inner and added a M6 nut to limit the opening of the aperture, this can be adjusted to hold the valve closed, or adjusted to allow it to travel to wide open. At 750rpm, when the phase of the moon is just right of course, all I need is about 3 to 5 mm of opening to keep the crankcase nice and empty of air.... Resonance now gone! This is the first time in history that I have had to tune a crank breather... Exhaust and inlet manifolds... done plenty.... breather...just one!
Keep it tuning....
Regds
Ed
PS.... TM2's replacement flywheel arrives tomorrow... this will be interesting....
PPS... on another subject... way off track from the current train of thought... I recall seeing on my injector pump(Botch unit, 034) ...on the riveted on nameplate, it is marked "9 deg BTDC"... Has anybody noticed this before? And if you have, what does this timing pertain to... any guesses? (Incidentally, TM2 has an identical pump, exact same markings....)