Hey guys,
Here are the latest happenings from darkest Africa.... Well its night time now, the roid is put to bed, I guess that makes it "darkest"....
Yesterday I eventually managed to get the CS plug out... Foolishly, when I commissioned this engine, I only gave the CS plug a light twist with a spanner to ensure it was tight... well, it was... tight up against some prime Indian debris... Amazingly, the green gunk they painted this creature with, managed to put up a bit of a seal, so not much leak was noticed during the early running from the CS plug... when the green stuff became a bit dodgy from the heat, a substantial amount of carbon had worked its way into the threads, successfully locking the plug in place..
Removal was a prize pain in the ass.... nothing that a spanner with 3ft of pipe couldn't sort out though... The reason for the removal, was to see the deposits in the IDI chamber... There wasn't much to be seen, way less than 1cc of total deposit was removed... most of it from the concave surface of the plug... there was relatively little to be seen in the chamber itself... it is almost as if the plug was a cooler point causing the deposits to adhere more easily to it perhaps...? I don't know... If you want to see pics of the plug and chamber inner, let me know and I will post a link to them...
I suspect, no, I am certain, that when I replaced the head gasket with my home brew version, I have gone down in compression... Hindsight is 20/20... Starting is more of a chore now than before... it takes a fair bit of turning over on the starter motor to get her firing... once running, a shutdown and restart by hand is easy... I am currently still running pretty much pure WMO(if there is such a thing) and only now and then switching to dino for short periods...(WMO is a far nicer running fuel for me, less knock and more power...) I have got thinner gaskets cut, I just need a bit of time to fit one... I am currently running on a gasket that is 1.2mm thick, aluminium. I want to try a .7mm gasket to see the difference it makes... Micrometer readings of the lip seal area of the original gasket indicate that it was squashed to about 1.05mm thick at cylinder wall... the 1.2mm I have in place now has definitely dropped the CR a bit, if my basic calcs are right, it would have dropped it by around 1 point if the motor was around the 17 to 1 when original... I did the calcs, just don't have them close by at the mo...
With this drop in CR, there is a definite dip in the power output and an increase in smoke while running under load.... A change to a thinner gasket will confirm it I reckon.... It seems as if WMO in particular, needs a bit higher CR than dino for reasonable running... pardon me if I have stated the obvious....Lol...
As to the economy impact of the lower CR... well ... difficult to say at this stage, but the influence seems minimal...
Another day in listerland draws to a close.... let's see what tomorrow brings!
Regds
Ed
PS... these damn UPS's are still pissing me around..... they are way too proud to run on a lister at 550 to 600 rpm.... This problem looks complex... pass me the bigger hammer please......