car blew up lastnight...

[3vs197]

and it happened after 4-5 beat runs from second to fourth gear winding it out to 7k each gear so i wonder if it just got pissed. and the valve was semi stuck in the head, it didn't just fall out, it had to be helped a bit so i wonder if excess friction caused it to stick in the head. i use pretty thick oil (0w-40) and maybe just a combination of things made it happen.

 

[Vxer1000]

and it happened after 4-5 beat runs from second to fourth gear winding it out to 7k each gear so i wonder if it just got pissed. and the valve was semi stuck in the head, it didn't just fall out, it had to be helped a bit so i wonder if excess friction caused it to stick in the head. i use pretty thick oil (0w-40) and maybe just a combination of things made it happen.

The heavier oil could be a problem. These newer engines use tighter clearances than older engines and is one of the reasons 5W-20 is typically used. Plus the fact that it was an exhaust valve that dropped, which is usually the case when running these motors at high rpm with longer duration cams. Sounds like you may have kissed the piston.

 

[3vs197]

i don't think it did though. the valve is not bent at all (i have had engines before where valves hit pistons and this does not fit that MO). and the valve is completely clean other than the break and i can't find a scratch on the piston.

 

[808muscle]

I know it sucks but man it could have been worse.

 

[HOLYWD]

Damn sorry to hear

 

[JeremyH]

the seal looks fine. but the part of the head where the valve seal slides over broke clean off the head. my buddy said sometimes due to friction the valve can get stuck in the head when it gets hot but it came out without too much trouble and it looks clean still and he said it wouldn't look so good if that were the case. i just don't know if this is a fluke or not.

After ready this, and other responses and that it definetly wasn't ptv contact, im pretty sure you were floating the stock valves and all that stress most likely fatigued and bent the stem. After you swapped in the stiffer comp springs you introduced even more pressure/stress and the valve stem eventual broke as you continued to rev it. This will also cause the seals to wear and allow more and more movement. As valve float occurs over and over it becomes easier and easier and starts doing it at lower and lower rpms, even after adding the stiffer comp springs. Hate to say I told you so but I mentioned this happening in one of your threads.

In case you havent seen videos like this you will be shocked at how much movement and harmonics there are in the upper rpms. The valve will spin and the stem will wobble all over the place.




I would definetly go ahead and but all new valves and seals in. Good luck!

 

[dysan]

Well damn. Are you going to need the tool again once I get it back?

Sucks to hear that this happened.

 

[3vs197]

^ ha ha, its actually still sitting in my parts dept. they called me yesterday and said they missed the cut off friday and that it would be sent out monday. but my buddy has a tool to do springs with the heads off that presses against the valve on the other side (like a big c clamp) so i should be good but if i need it i know where to turn.

and light blade you might be right. and if thats the case then i accept my "punishment" fully. a set of lightly used heads with a valve job and better valves not that i have springs should fix my issue.

 

[slow06stang]

Here is the link to pictures of the passenger side head I have. It will be shipped exactly the way it looks in the pics. https://picasaweb.google.com/ahalbr...authkey=Gv1sRgCNnfivXt_vGepQE&feat=directlink