Remember, a compression test tells you essentially nothing about oil consumption, same thing with leakdown. You could have totally hosed oil rings, which would give you great compression (essentially always a wet test). I'm not buying oil past the outside of the guide. How about baffles in the valve cover? Is there oil in the intake manifold?
Bill Cardell TurboDog's Dad Flyin' Miata 1-800-359-6967 (sales) 970-464-5600 (tech support) www.flyinmiata.com www.fmwestfield.com -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Rob Ebersol Sent: Wednesday, November 04, 2009 1:18 PM To: Miatapower Miata Power Subject: Smokey 1.6 I dropped a low mileage 1.6 into my "new" Miata and it has suffered from horrendous oil smoke on startup. It also burns it at high rpm, but you'd have to look very hard to see it (like rev'ing in the driveway while looking at the rear of the car). The engine sat for four years, so I wasn't surprised. But the problem never got better. I figured a compression check would reveal whether it was rings or not. So I did a "stone" cold compression test and got the following numbers: 193-192-189-188, which looked excellent to me. My old Miata had compression numbers in the high 140s and never smoked like this thing. I assumed at that point it was the valve seals. So I've replaced them all and still have the same symptoms after a few cold starts and ten miles of driving. All the valves fit snuggly in the guides and sealed very well under air pressure. Also checked the entire crankcase venting and it's ok too. I thought maybe carbon was showing high compression levels, but there's barely anything on the piston tops (head is spotless- looks maintained). So I'm left looking at other possibilities. The only thing I could come up with was oil leaking between a guide and the cylinder head bore that it passes through. Thoughts? thanks, Rob _______________________________________________ Miatapower mailing list [email protected] http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower _______________________________________________ Miatapower mailing list [email protected] http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower
