anyone ever had this happen to them... how often this happen... happened to a friend of mine...

 

i would assume that it would cause the motor to smoke a hole hell of a lot, i havent heard of them breaking so much as them wearing. Just causes a lot of oil to burn and such. Easy fix really, take off the head and have them mic'd and replaced as well as a valve job done should only cost around $200

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by urbansi &raquo;</TD></TR><TR><TD CLASS="quote"> Easy fix really, take off the head and have them mic'd and replaced as well as a valve job done should only cost around $200</TD></TR></TABLE>
If you can get all that work done for 200$ I'd be very surprised-or scared.I'm not sure.....

Mosy places I know of and have worked at charge at least 10 bucks a guide to replace + the price of the guides.Thats 200+ right there w/o even a valve job.Then you have to include the tear down and clean and reaasembly w/new seals.Also don't forget about refacing the valves if they are reuseable.

 

We broke one a couple of years ago. We think it was from the extremely low air temps.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Garcia-Racing &raquo;</TD></TR><TR><TD CLASS="quote">We broke one a couple of years ago. We think it was from the extremely low air temps.</TD></TR></TABLE>This happened to a freind of mine.he broke 4 crower valve's and 4 guides.Why do you think low air temps caused them to break?

 

That was just our best guess. No proof really, but our iat was around 54 deg. before the methanol.

 

is it possible a tweaked valve had anything to do with it ?? maybe just an old worn valve ?

 

I don't remember the valves being bent. We did bend a set of Carillos at the same time, but they didn't touch. This was just our best guess when we took it down to Portflow. We replaced them and shaved them down now, and no more problems.

 

was it just one or all of them ?

 

just one

 

This happened to my Kia. 2 of the OEM valve guides snapped off at the point where they penetrate into the runner. One of them was still on the valve stem, the other broke apart and chewed up the combustion chamber a bit before harmlessly passing through the exhaust valve, also f-ing up the T3 turbine I had in the car at the time. No idea why it happened. Car ran fine for another 50k miles before I broke some ringlands.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Garcia-Racing &raquo;</TD></TR><TR><TD CLASS="quote">That was just our best guess. No proof really, but our iat was around 54 deg. before the methanol. </TD></TR></TABLE>

LOL 54* F is 'extremely low temp'?! Come to New England, oh about right now! I tune all winter long, temps in my dyno cell have gotten down to ~20*F even with cars running large methanol injection systems. No cracked valve guides!

Ive seen a case where an engine over-revved, the valve probably touched the piston ever so slightly but didn't bend. A couple of weeks later a valve guide broke off and wedged between the seat and valve. The valve had slight evidence of the contact but was 100% straight. I think it put just enough side loading on the guide to crack a piece off.

 

No thanks, I love Cali. Just or best guess, I'm sure there are other things that factor in.