Grrrrr...
All set to go flying today despite the cold weather, did a couple of minor things, fueled the tank up, started the Mosler and let it warm up while putting on my jacket and scarf... and it quit. Figured no big deal, it was idling too slow in the 40° temps, but it wouldn't restart... and then I realized I had zero compression on the RH cylinder. Uh-oh. Better on the ground than in the air, though!
Pulled the valve cover, both valves appear to be moving correctly, clearance when closed looked more or less correct, though I didn't have a feeler gage handy to check it. I did manage to figure out that the exhaust valve isn't closing, as when I put my hand over the exhaust pipe I feel pressure when I move the prop even when the exhaust valve should be sealed. Hard to say whether it's stuck, burned, or just some crud preventing it from sealing.
Lacking a borescope, I guess the only thing to do is pull the cylinder head, which I'll do tomorrow, and see what I find. Anybody know offhand if I need to remove the rocker box first? These are Scat heads, which is what Mosler used. It looks like it interferes with access to the head bolts, but I didn't look too closely.
Any suggestions or advice? VW derived engines are new to me.
Dana
All set to go flying today despite the cold weather, did a couple of minor things, fueled the tank up, started the Mosler and let it warm up while putting on my jacket and scarf... and it quit. Figured no big deal, it was idling too slow in the 40° temps, but it wouldn't restart... and then I realized I had zero compression on the RH cylinder. Uh-oh. Better on the ground than in the air, though!
Pulled the valve cover, both valves appear to be moving correctly, clearance when closed looked more or less correct, though I didn't have a feeler gage handy to check it. I did manage to figure out that the exhaust valve isn't closing, as when I put my hand over the exhaust pipe I feel pressure when I move the prop even when the exhaust valve should be sealed. Hard to say whether it's stuck, burned, or just some crud preventing it from sealing.
Lacking a borescope, I guess the only thing to do is pull the cylinder head, which I'll do tomorrow, and see what I find. Anybody know offhand if I need to remove the rocker box first? These are Scat heads, which is what Mosler used. It looks like it interferes with access to the head bolts, but I didn't look too closely.
Any suggestions or advice? VW derived engines are new to me.
Dana
