Burnt Valves
Thread Starter
|
Senior User
Joined: Nov 2004
Posts: 195
Likes: 0
From: Wilton, Ca
Burnt Valves
I am curious. What causes a burnt valve.I have put just 25,774 miles on this motor,And know it has two burnt valves.I have taken really good care of this.tune up every 5,000(plugs cap & rotor)
I pull my 5th wheel and have not had the RPM over 3,000.I keep a close watch on the tack Oil change a 3,000.Maybe the gas. I run reg.
This motor is 4yrs old so the warranty is GONE FINISHED CAPUT 3/36000
WHAT A BUMMER $$$$$$$$
I pull my 5th wheel and have not had the RPM over 3,000.I keep a close watch on the tack Oil change a 3,000.Maybe the gas. I run reg.
This motor is 4yrs old so the warranty is GONE FINISHED CAPUT 3/36000
WHAT A BUMMER $$$$$$$$
Posting Guru
Joined: Sep 2003
Posts: 1,192
Likes: 1
From: lino lakes, mn
cobustion chamber heat from a lean run ie vacum leak low ,float level or timing, to thin of a valve margin, poor valve adjustment or bad valve material to name a few. What size engine are we talking about?
Postmaster
Joined: Jul 2003
Posts: 2,544
Likes: 2
From: okc
when it was rebuilt, are you sure all the valves (if any) where replaced?? alot of head shops around here only change out unburnt valves if you ask them to, cause it costs quite a bit more....my money is on either a lean condition on those cylinders from a vacuum leak, or just bad valve seals...
Posting Guru
Joined: Mar 2006
Posts: 1,118
Likes: 0
From: Williamson, NY
I just tore down my 77 302 that I just bought and I found that just about all of my exhaust valves were burnt (valve coated with white deposits). During the tear down I found two vacuum hose connections that were not connected, which is good supporting evidence that vacuum leaks will cause burnt valves.
Jim
Jim
Elder User
Joined: Feb 2005
Posts: 669
Likes: 1
Running too lean and/or incorrect timing are both common problems that can go unnoticed until you burn valves. If you haven't torn it down yet then you can check for both of these. I would want to get to the root cause of the problem before you just pull the heads and get them repaired. Otherwise it will happen again. jmho.
Good Luck,
Tracy
Good Luck,
Tracy
