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Currently, have a new motor build. Less than 10,000 miles. Schrick 292 cam, IE heavy duty rockers, BMW springs. I'm on my 5th oil change. Gibb's hr1 15w50 with valves set at 1000, 2500, 5000, 7500 and again at 10,000. We noticed at mechanic's shop, pitting on the new when installed schrick cam. Has anyone had this problem? The cam is pitted not scored. Lobes seem ok on IE rockers but hard to tell. Can feel the pits with a screw driver. Will be cutting oil filter open on Monday and sending out oil sample. We are considering pulling head and cam. Any advice? Has schrick had problems or should I be looking at the rockers? 

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Motor was built by a great shop and all break in procedures followed. Looks to be a metallurgical problem? No heat marks on cam. Oiling system in head working correctly. Oil pressure good. All squirters open and flowing over each lobe set. Verified with cover off. Anything else we should consider? 

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Pitting being in the highest load area of the lift, either the cam has a  metallurgic problem or the load is overwhelming the film strength of the oil.

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As Jim said contact Schrick, if it's cam hardness they would probably be aware of the problem. Just out of curiosity does the cam have Schrick cast into it in big letters, rumor has it that they have started getting the cam blanks offshore and these don't have the name cast in.

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Data point: I’ve seen and encountered similar wear when using Schrick camshafts combined with the Ireland HD rockers ... they don’t always get along. I was able to remedy this by using an oil with high zinc content. (Early on, I noted Mobil 1 was not a friendly companion.)

 

Another possible factor: What valve springs are you running? -KB

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     Oil has been high zinc content Joe Gibbs Break-in Oil  then the Gibbs HR 1 with zinc for these engines. Valve springs are stock BMW. Didn't want extra wear on the valves and seats. Street engine- revs limited at 6800 and has never gotten there.

     kbmb02 - What did you end up doing? Just changed oil? We are currently are awaiting results of oil analysis. What did you determine to be the problem with the IE rockers?

     The IE HD rockers were my first suspect as most of the items I've gotten from IE have been more of a headache than I'd rather discuss. This is their only parts in my engine and I've been concerned knowing that... It seems by your statement, so justified.

    Anyone else have the same problem and what was your outcome?

Thanks

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(edited)

I have had that problem,

but it was zddp and spring pressure related- significantly higher

pressures than stock.

 

I have used stock (Febi) rockers-

one set of IE HD's, but no unusual problems with them, in particular.

I used a break- in additive, before the Gibbs oil was available.

The stock rockers are plenty tough UNTIL they

start floating, and then they pop.

 

Outcome?  I came out of the experience poorer and wiser.

Several cams, several sets of rockers munched.

Used the break- in additive, and it didn't happen again.

 

t

 

Edited by TobyB

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Thanks Toby, so what would your recommendation be? 10:1 engine, 292 schrick cam, twin Dcoes, msd rev limited, header, all balanced, ported, street engine. Pull the head, refinish or replace the cam? Febi rockers or other suggestion? If febi should we clean them up, shot peen? Reuse BMW stock springs. All with plenty zddp + the Gibb's. Just don't want same problem again. Thx

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2 hours ago, GirtAllerton said:

 kbmb02 - What did you end up doing? Just changed oil? We are currently are awaiting results of oil analysis. What did you determine to be the problem with the IE rockers?

 

I changed to a different oil ... and still use Ireland HD rockers in most of my builds (with/without Schrick cams).

 

Based only on my experience, yours sounding more like some other issue now, especially if cam was fine at previous valve adjustments. Who did the last valve adjustment? Set to what clearance?

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No the problem was progressive I believe, just when I was at mechanic had him look at it. Same guy myself with same gauge to .008 at every oil change. Haven't had to adjust much. Maybe a little tight on exhaust side with each adjustment. Less adjustment each time needed.  Tending to think your initial response and Toby's are correct. Unhappy marriage between the cam and rockers. Question is pulling head checking and rebuilding. So what do we need to do to make sure we are 100% this time. What to put back in? I'm ok with buying a new schrick cam if needed but ie rockers don't know. Looking for input. Thought I made the decisions right the first time. Should have had enough zddp with gibbs break in oil and prelube. All done by experienced Porsche BMW mechanic. Thx for feedback.

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3 hours ago, GirtAllerton said:

 

     The IE HD rockers were my first suspect as most of the items I've gotten from IE have been more of a headache than I'd rather discuss. This is their only parts in my engine and I've been concerned knowing that... It seems by your statement, so justified.

 

 

Bear in mind that the schrick cam and the IE cams are coming from the same source now.  Be aware that the 292 cam and stock springs work ok, but you really should have considered slightly stiffer springs (not full-on IE duals or schrick duals) with that cam if you are going to run the engine up there.

 

I'm kinda with Ken here as that it could be a valve-lash problem.  Possible that the initial valve lash was done prior to the head being torqued.  The initial startup/warmup cycle would have then meant the valve lash was close to non-exhistent.  That combined with initial break-in could have resulted in the marks you see.  

 

In my mind, I'd keep an eye on it.  If it progresses to get worse, take out the cam.  If it stays the same, then Bob's your uncle.

 

 

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