I have a 1988 sundancer 340 with twin 454s. There seems to be oil blowing back through the hose out the valve cover. I am losing about 1 quart between oil changes. The spark filter( or what ever you call it) is black and full of oil. When I took off the cover I could smell oil and could see a small puddle on the intake. My question is, is this a lot of blowback? The engines only have 100 hours since rebuild.
oil blowback
- Thread starter wetbar
- Start date
- Oct 6, 2006
- 12,155
- Boat Info
- 1996 450DA
- Engines
- 3116 Caterpillars
I think it is too much. After 100 hours, I would think the rings should be as seated and blow-by would be negligable by now.
- Nov 26, 2006
- 7,628
- Boat Info
- 2008 44 Sedan Bridge
- Engines
- Cummins QSC-500's
Straight Drives
If rings don't seat after a reasonable period of time on a re-build, you may have gotten the wrong size of rings. I did this on a 1972 MGB lower end re-build. We replaced the rings not realizing that the top end had been bored. It burned oil for a long time before I pulled the heads off to find the cylinders marker +.020. I popped on new, correctly sized rings, and within a short period, all was well.
- Nov 26, 2006
- 7,628
- Boat Info
- 2008 44 Sedan Bridge
- Engines
- Cummins QSC-500's
Straight Drives
I wouldn't go there, yet. It's just something to think about. It happened to me.
