Re: Cracked exhaust manifold.

Posted by casebro on Wednesday, September 26, 2001 at 10:22PM :

In Reply to: Cracked exhaust manifold. posted by Robert on Wednesday, September 26, 2001 at 12:14PM :

Because at the top of the exhaust stroke, while the exhaust is still open, the intake opens, (yes, it's called overlap). Since there is a vaccuum in the intake manifold, air is sucked in through the crack and open exhaust valve, then the exhaust closes , trapping the air in the cylinder. The fuel containing intake charge is diluted the outside air, causing a lean condition. Since leanness equals heat, you burn your exhaust valve.

Follow Ups: Going further.... - Brian in Oregon 2:21AM 09/28/2001 Re: Going further... BRIAN; PLS Explane futher. - Mike M. 0:53AM 09/30/2001 Re: Cracked exhaust manifold. - Robert 0:39AM 09/27/2001 Post a Followup Name: E-Mail: Subject: Message: Optional Link URL: Title: Optional Image Link URL: This board is powered by the Mr. Fong Device from Cyberarmy.com