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Discussion Starter #1
anyone had a camshaft failure? I had a customers' car come in this past week and #2 intake lobe was cracked and loose on the cam tube. The dealer parts guy told me they hadn't seen a single cam failure yet
 

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Lets hope that its not a common occurrence...
 

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anyone had a camshaft failure? I had a customers' car come in this past week and #2 intake lobe was cracked and loose on the cam tube. The dealer parts guy told me they hadn't seen a single cam failure yet
Any other data? Did they over-rev? Underoil? Miles?
 

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Could you post images of th failed cam? I'm super curious to see what you mean - I don't think I've ever heard the type of cam shaft failure that you are describing. I'm actually kind of shocked that it's even possible.
 

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Discussion Starter #5
Fiat is using a cam that is a hollow tube with the lobes pressed on rather than a solid piece with ground lobes. When the car came to me it was full of oil but the customer told me he had added oil. The lobe failure doesn't appear to be oil related though. I'll post pics after I get to the shop today
 

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Fiat is using a cam that is a hollow tube with the lobes pressed on rather than a solid piece with ground lobes. When the car came to me it was full of oil but the customer told me he had added oil. The lobe failure doesn't appear to be oil related though. I'll post pics after I get to the shop today
Wow, thanks for the info. That is amazing. I've seen camshaft with hole drilled through in the middle, but I don't think I've ever seen one where lobes are pressed in. Things I learn everyday!
 

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Discussion Starter #7
here are two pics; one shows cylinder #1 in normal condition, the other shows cylinder #2 intake lobe has moved over against the exhaust lobe and is clearly cracked. The lobes are powder metal and pressed onto the tube. Once the lobe cracked it now spins on the tube. There is more pressure on the spring in the vvt assembly than the lobe could overcome, so it would never open the intake valves

 

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Discussion Starter #11
Ford has been using this for a couple of years on the 4.6 motor. Fiat is feeding oil through the cam tube, so it would take some engineering to design a solid core camshaft
 

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Thanks for the picture and the information. That is fascinating, I've never seen that before. Powder metal lobes for the camshaft! Honestly, I don't know how I feel about it in my car, but... It was really educational! I wonder when we'd see 3D printed crankshaft and stuff like that.
 

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Hollow cams have been around for ages. As for a tube with pressed on lobes, it's becoming the new norm. There are plenty of engines out there that are like this. It's just that nobody knows, thus they never worries about it. There are plenty of other things in various engines that if people knew about, they would lose plenty of sleep. At least this is not like the old days where cams would wear out or a major victory to get a motor to 60K before it needed to be rebuilt.
 

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Hollow cams have been around for ages. As for a tube with pressed on lobes, it's becoming the new norm. There are plenty of engines out there that are like this. It's just that nobody knows, thus they never worries about it. There are plenty of other things in various engines that if people knew about, they would lose plenty of sleep. At least this is not like the old days where cams would wear out or a major victory to get a motor to 60K before it needed to be rebuilt.
Yeah, really. I mean, hollow cams I have seen, most racing engines have been using them for a long time. I still think they are super sexy. But this pressed lobes are totally new to me, I just didn't know anything about it. So fascinated.
 

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Pressed on lobes.......bah!

At lest they could weld them on?

Super Glue?

Something other than press fit?

Tedolph
 

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Discussion Starter #18
once the lobe cracked, that allowed it to spin on the tube. Most of the other cams I've seen of this type have a flat that prevents the lobe from spinning
 

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once the lobe cracked, that allowed it to spin on the tube. Most of the other cams I've seen of this type have a flat that prevents the lobe from spinning
Hmm. That's interesting stuff. Curious how it could have broken.
 

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