The story begins late last year when I purchased my 06 WW RS. I am in NJ and the car was shipped to me from California. Couldn't wait to get it.....It had all the right mods such as a Buschur 2.3 bottom end, Buschur stage 3 head, FP BB Green turbo, and a ton of other mods including Kelford 272 cams.
The car came off of the trailer and I drove it around, getting on it here and there but mostly driving it pretty easily. I pick up my friend, who was instrumental in helping me find the right car, and we proceed to drive around. I hand the keys over to him and he proceeds to get on the highway and does this really nice 4 gear pull to just under 7k rpms, then he proceeds to take the off ramp and enters another highway. At that point the car dies, no odd noises or anything. He holds the clutch in and coasts to a stop and just before he stops we hear a noise. After this the car sounded like it had no compression. Turns out the valves hit the pistons and also one of the rockers wedged between the cam and the head and cracked the head.
After this I had the car towed to my friend's house, he has a very large garage where it will be much easier to work on. The previous owner and myself go back and forth about how this happened but couldn't find any answers when I tore it apart
Fast forward to Sunday when I finally had a great day to work on the car. I put the head on, bled the lifters and installed them, put the rockers on, and put the new GSC-R2 cams in. When I removed the Mivec gear I found that the old Kelford 272 was damaged and so was the Mivec Intake cam gear. I am glad I finally found what caused all the damage butI never expected a 1k mile old cam to fail like this.
Thank god I decided to switch cams otherwise I probably would have had this happen again.
This happened 40 miles after delivery of the car. Thanks to Nick and David @ Buschur, Brian @ STM, Rob the original owner, and any other people who helped me get it back to how it was....maybe even a little better since I couldn't resist a few changes.
Has anyone else had any issues similar to this?

Intake cam


Mivec Cam gear



Head Damage

 

The dowel was still in there but it was cocked sideways and the part towards the cam gear was ground down. The cam gear bolt was on tight and the cam gear it self was tight on the cam, I had to use a mallet to get it off. Not sure how the dowel got ground down since alumibun is much softer than the steel that pin is made of. Also not sure how the cam was damaged like that if the dowel is the same material as the cam....

Any thoughts?

Here is the car when it came off of the hauler

 

Damn I really wanted that car when it was for sale!

 

Well.....it could've been you then....
LOl, you should be thankfull it has cost me thousands....and then there is the "might as well do it now"parts list!

 

Looks to me like the pin wasn't lined up on the cam gear when the bolt was tightened down, and then the gear spun on the cam.

 

If this was the case the gear wouldn't have lined up with the timing belt correctly and it would have been loose on the cam.
The cam gear was tight as well as the bolt.



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Actually the gear could still have been lined up with the belt, the cam would just be off from where it should be. And if the bolt was tightened down it would hold the gear in place until alot of torque was applied (spinning the motor fast).

 

I meant that it wouldn't have close to the valve cover, it would have been noticeably further out then he other cam and that would be visible. I checked pics of the belt before and the belt is the same on both gears.
Also, the gear would be loose on the cam and the bolt that holds the gear on would get more loose as the dowel wore into the cam.




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This is more of what came first, the chicken or the egg?

If the timing belt jumped, due to a worn belt or tensioner I could see there being so much Tension At high speed, that it would tear up the cam like this since the valves would have no where to go but bend and jam up the cam. Otherwise maybe the pin wasnt all the way in the cam gear.

Something caused the cams to come to a stop, and since it happend to both of them and not just one i dont think it was a bad cam.

 

This Buschur motor and head are less than 1k miles old and all of the timing components were new. The timing belt looks fine and it was basically brand new. Both tensioners were brand new.
When it happened the car was at 3k rpms and no under any load either. Tearing the motor apart there was nothing out of the ordinary and
I couldn't figure out h what happened. This was the only sign of anything out of the ordinary.

I could see the theory of the cam gear being worn becuase of the valves hitting the piston but not the damage to the cam. From my experience I believe that there was something wrong with the installation or somehow the cam failed by the dowel pin wearing into the cam like that. The pin and the cam are the same material and one jolt wouldn't do that to the cam, I think that it was caused by repeated back and forth motion and by the looks of the cam gear I think the same thing about that.
I think that something happened, not 100% sure what, but the intake cam gear slipped on the cam and caused the intake valves to hit the piston and then the exhaust valves hit the pistons as well since the timing slipped.
Once the intake gear was off that much I am pretty sure it would cause the belt to jump once the intake side hit like the valves.

 

You just said what I was trying to tell you, the cam gear was not lined up correctly when they put the gear on and torqued it down crushing the pin into the cam/gear, it ran ok for 1k miles and finally spun the gear on the cam.

 

I hear you. I am not saying that is wrong but if that were the case you would be able to tell that the gear wasn't on all the way just from the position of the belt on both cam gears.
Also, that doesn't explain the end of the dowel pin being ground down. I don't think the aluminum from the cam gear would be able to cause this to the dowel. Also, I don't think that the damage to the cam could've happened from 1 good jolt. To me it looks as if it had been moving back and forth for a while.
If the cam gear was in the in the wrong spot and the dowel was pressed into the cam gear by tightening the bolt wouldn't that be almost as good as the dowel being in the hole? It would of course be out of time but it would still be secured into place. Aslo, the cam gear was tight on the cam and the bolt was tight.....had to use a half inch breaker to get the bolt loose....which might support some of your theory.

This is my best educated guess as to what happened.

LOL, just my luck. The car works great for 1k miles then breaks 40 miles after it gets in my hands!

 

Well either way I think its safe to say that it wasn't a defective cam but installation error, as it usually is lol.
Good thing is you caught it, Good luck with your build.

 

I cant see that well from the picture, but if that end of the cam is galled id say it was moving back and forth. Were the dowel pin the correct size?

That does suck, good luck on ya build!

 

Also a possibility that the bolt itself was not tight originally, and when everything went it forced the gear out, thereby making it seem the bolt was tight..

We could go on all day with the guessing game..

Pretty car though, me likey!