by chuckstarck » Tue Oct 04, 2011 3:09 pm
I have three of these, all are Torpedo version, the beginning of time where I come into the picture.
Two are still in excellent running condition but the third just isn't right.
It has virtually no compression. You can start it with a starter but not by hand which is my preference for these engines as they will start in the first if not the second flip after a simple two turn prime and they do it every time for me.
This engine will start and run hard if you keep the rpm up but if you drop to 1/3 throttle, it will start to sag, like either rich or lean, sounds more like lean but that's not the issue. Sometimes you can not get it to fire at all because the compression is nada.
So the choice, simple, put a ring in it, it's 40 years old and deserves a ring. The old one has a .0013 gap, gee that a lot but others have even run well with that gap. Never the less, put a ring in it. The new ring is so tight you can not hardly get just the ring in the cylinder. So I scotch brite the inside to get rid of a glossy black residue, not carbon, looks like the glaze from a fire place on the glass. The ring fits and it doesn't bind and it really looks like this will fix it. Noop, wrong guess. So I put the head in soapy water and spin the crank, no leaks around the head and none at the plug.
When the piston in the downstroke passes the bypass, it really pops which tells me that the ring is sealing 'down' but not up. Go figure, I need it going up.
What's your opinion on the problem? I thought if the ring were not sealing to the piston, it would show in the down stroke as the crank pressurizes as well. Another bad guess. I'm stumped.
:?: