1938 S Preforms Miracle (awaiting Pope's approval)

[guzz...@gmail.com]

Since getting the S running again after over 30 years I noticed I had to adjust the compression release a couple of times to properly stall the engine. I explained this in my head as working out the kinks that were in the end of the cable as it was a bit of a mess but I didn't want to replace it due to its original patina. I had just had it out running the day before so when I headed off to my parents house to show my bed ridden father my new toy I only made it a little over a mile before the bike sounded as though it had an exhaust leak and was losing power. I made an immediate u-turn and headed back for home and noticed at a stoplight while looking for the exhaust leak that fumes were shooting out of the carburetor onto my leg. To my surprise the seemed quite extraordinary and meant something was very wrong with the engine. But the engine continued to run even though down on power all the way back home. After checking the inlet valve lash I could only assume I had burn or broken a intake valve. So after removing the intake valve/spark plug plug and looking inside the engine, everything looked beautiful! I then reached up and touched the exhaust valve push rod only to find over a quarter inch of valve lash. This explained the compression release adjustments I had to make to get the engine too die. 

So here's what was really happening. The intake valve would open to suck in combustion fluid, come up and fire the piston which would go down and come back up for the exhaust stroke except the exhaust valve either didn't open or open very slightly, only to compress the combusted gases awaiting the intake valve to open and blowing it out the intake valve. But as the Piston came down and the intake valve open, it's still had enough time to suck in some combustible fluid and come back on compression stroke and fire again. This went on for a mile and a half on my way back home. I consider this a miracle that the bike continued to run and not burn up in a ball of flames! I'm still awaiting the Pope's approval of this miracle but hope to hear from the Vatican soon. I will keep youin touch.

[dryde...@aol.com]

As long as the Pope doesn't mistake "compression" for "compassion" while translating.........

Upstate Mark

Sent from the all new AOL app for Android

--
You received this message because you are subscribed to the Google Groups "Guzzi Singles" group.
To unsubscribe from this group and stop receiving emails from it, send an email to guzzi-single...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/guzzi-singles/0d73d77f-c116-49f3-9c65-beb3e0cf212fn%40googlegroups.com.

[Richard Wood]

More likely the exhaust valve was partially open all the time due to badly adjusted decompressor, which lifts the exhaust valve to stop engine or aid turning engine over compression. This would have created leak on power stroke severely limiting power, increasing engine note etc. It's possible that leaked power pulse bounced back from exhaust system and got blasted back through carb on inlet stroke. 

Whatever, I agree it's a surprise the engine ran at all but not a religious miracle ;)

Richard