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About 10000 miles ago I did my engine rebuild and fitted a new inlet cam as No2 was very worn. Now it has wiped my new cam even more( only number 2). What can be done to prevent this? I checked for any blockage in the oil feeder pipe in the cam cover and all is clear.
 

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Start using a ZDDP additive to your oil. Modern oils have reduced ZDDP to make them more catalytic converter friendly. A cam has a very high pressure friction surface which is more likely to break through the film than most other turning parts on your engine.
http://http://www.ttalk.info/Zddp.htm
 

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Unfortunately Addertooth is correct. I ate a piston in my yacht. Had a new motor built and within 6 hours of use I lost my cam. Of course you can't just change out a cam like a car. I had to pull the boat out of the water, pull outdrive, and pull the motor again just to change the cam. My mechanic recommended an additive to put back the properties they no longer put into oil and I have been ok since. Unfortunately you have to add it back in yourself.
 

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If the cause is the lack of ZDDP, instead of purchasing a ZDDP additive, you can try using non-API certified oils (so they are not OEM compliant) which contain the higher levels of ZDDP as was the case with all oils in the past -- Redline is one example.
 

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Diesel formulations have more ZDDP, due to no catalytic converter (typically). Engines which were designed before catalytic converters are especially succeptable to modern low ZDDP oils. High reving modern engines can have problems too.
 

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Discussion Starter #8

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If the cause is the lack of ZDDP, instead of purchasing a ZDDP additive, you can try using non-API certified oils (so they are not OEM compliant) which contain the higher levels of ZDDP as was the case with all oils in the past -- Redline is one example.
I knew there was reason I liked paying the higher price for the Redline. 10w40 as recommended to me as the best to use (standard oil, not race).

Richard - you can also get the additive on its own...
Red Line Synthetic Oil - Motor Oil for Racing - Engine Oil Break-In Additive

And Bruss Simon says to break in the cam >2500 RPM for >20 minutes to "get it happy".
 

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Apologies for bumping an old thread, but I am reading up on this cam issue as i want to buy an Elise, as soon as i find one. ( green or orange?)

Anyway, I have tons of time with 911's, old Ferrari's blah blah. Been using BG MOA oil additive in everything I own that burns gasoline as its a great additive with needed stuff for an older engine, with no "snake oil". im a regular user of Redline and Royal Purple, but I add the BG MOA anyway.

Its unclear to me as a non Elise owner if this cam issue has been resolved yet. I am hoping if I find a car the owner will allow a basic inspection as this is my only real concern, other than the oil lines. :)
 

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It really hasn't been resolved. Some postulate that running higher then factory spec valve clearance helps the issue. It's not a major issue since a new cam and rockers is less than 300 bucks. You can also get different cams.
 

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Is this also possibly caused by the factory cams being sub-par as far as surface hardness goes compared to other cams in high-performance, variable valve timing engines?

Are aftermarket cams, such as the Piper cams, more wear resistant? Has anyone ever wiped an aftermarket cam?
 

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Is this also possibly caused by the factory cams being sub-par as far as surface hardness goes compared to other cams in high-performance, variable valve timing engines?

Are aftermarket cams, such as the Piper cams, more wear resistant? Has anyone ever wiped an aftermarket cam?

I believe that there was an annealing issue with some of the early cams that were put into the early Lotus engines which made the cams too soft.
 

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there are plenty of high mileage elise/exiges without any cam issues-cam wear is going to happen it is a wear part but proper oil changes with proper oil (ZDDP is a must!) and you should be fine.

There are definitely some unlucky few who have had cam issues, and some have had luck with Lotus Cars getting motors replaced as a result.
 

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I believe that there was an annealing issue with some of the early cams that were put into the early Lotus engines which made the cams too soft.
We had the rockwell hardness tested on intake and exhaust cams, wiped, and non-wiped. Hardness number came back the same across the board.
 

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So to summarize, the three major factors are (in no particular order):
Lubricant
RPMs of typical use
CAM lash settings
 

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We had the rockwell hardness tested on intake and exhaust cams, wiped, and non-wiped. Hardness number came back the same across the board.
How about the hardness of the follower pad on the rocker? Any testing been done on that? (When I replaced my intake cam, the rockers were severely eroded - any chance the rockers wear first and cause the damage to the cam?)
 

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This thread is very useful to me. My 06 Elise won't shift cams anymore and at 6G it sounded like ball bearings in a dryer. I removed the valve cover and found the lift bolts in perfect condition. The number two high-lift lobe was badly worn and one face was galled. A strip of metal across the wiped area on the approach to the lobe has been torn out. It's about 3/16 inch wide. I imagine the rocker is ruined and maybe all three of the others. I can order a new cam and rockers from Monkey Wrench. Is there any reason not to? ZDDP sounds like cheap insurance. I used to formulate the diesel engine oil for a major oil company and I always thought they'd make great racing oils. It looks like some here think that's a good idea. I'd show a picture of my bad cam if I knew how to insert it.
 
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