Blowby!

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Jun 8, 2008 | 05:19 PM

N7ghtwolf

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Joined: Apr 2006

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From: Savannah, GA

Blowby!

A little over a month ago I started to notice some blowby, its gotten worse but I have no idea whats causing it. Compression is close to perfect in all cylinders!

What else causes blowby? I know my timing has been needing to be checked for a while now!

Jun 8, 2008 | 05:39 PM

srercrcr

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Blowby is simply crankcase fumes getting past worn piston rings. If you have it, you have worn rings, which means you have poor compression.
Where are you seeing this blowby? Is the PCV valve and line hooked up?

Jun 8, 2008 | 09:39 PM

fmc400

MSEE

Joined: Apr 2004

Posts: 10,386

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From: Austin, TX

Right on the money. Check PCV valve and breather filter, as well as respective lines.

Jun 12, 2008 | 01:16 AM

Redneck-Cowboy

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Joined: Jul 2003

Posts: 997

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From: Weston, Nebraska

Yeah hopefully it's just your PCV system. When I started gettin major blowby outta my engine I couldn't figure out what was going on either since the comp was still moderately good for 300,000 miles, so when I did yank it (startin to tick/knock under a load) I found a broken ring land on the #6 cyl, didn't mess up the wall though, the piston just fell aprat when I pulled it out of the cylinder......lucky.