naviathan Posted August 8, 2007 Author Share Posted August 8, 2007 Well, hopefully I won't have to start over with a different short block entirely, this engine has been great with compression numbers upwards of 170. I'm going to drop the pan (I hate dropping the pan on a ZX) clean it out, pull the pump, check it out, I have another turbo oil pump still in the box fortunately and hopefully I'll get something out of MSA. If not, I'm convinced this a Schneider cam problem after reading the archives this seems to be quite common. Of course those threads that had these issues were immediately ridiculed by many many people saying it was lash pads or clearances or anything but the "KNOWN" problem with Schneider's soft cam blanks and lack of hardening. Quote Link to comment Share on other sites More sharing options...
Zmanco Posted August 8, 2007 Share Posted August 8, 2007 I went the Delta Cam regrind route as well. Result was a grind equivalent to the MSA/Scheider stage III. They also resurfaced my rockers for a nominal amount. I did have to change lash pads. Turns out that Delta "swore" that the regrind would need a particular size (don't remember what value here at work) so I bought a set from Courtesy Nissan. Then I measured the wipe for each valve. Turns out he was right - I didn't have to change any. I'm not trying to contradict Braap's earlier advice - I suspect I was lucky that my head had never been rebuilt before me. My point is that for a lot less than MSA charges, you can use the cam and rockers you already have to get the equivalent specs to their cam kit. Naviathan, I realize you're already committed to the MSA path, but perhaps others will consider this alternate path. Take the money you save and put it into your suspension:) Quote Link to comment Share on other sites More sharing options...
naviathan Posted August 8, 2007 Author Share Posted August 8, 2007 This is very good advice. I was in Iraq at the time I was purchasing parts so I didn't have the option to pull a cam and send it out for regrind. I was hoping that the MSA/Schneider route would be worth while seeing as I wasn't going super dramatic in my upgrades, just a mild push. Seems I'm paying for that now. Quote Link to comment Share on other sites More sharing options...
WizardBlack Posted August 8, 2007 Share Posted August 8, 2007 Sorry to see those problems. I have had a few ppl I know go through the same issues in the past on other motors. I will say this: flush every single route of oil. Those metal particles get everywhere and if any one of them isn't flushed it will circulate back through the motor again and take the bearings out. I've seen it multiple times. IMHO, flush the block's oil passages, replace the oil pump, have the head flushed, etc. Hope everything works out for ya. Quote Link to comment Share on other sites More sharing options...
naviathan Posted August 8, 2007 Author Share Posted August 8, 2007 Ok here's some more pics, this time of the rocker arms. The wipe pattern is lower than it was when I checked it initially, but it's the same across the board, why just the certain lobes wiped out and the others are fine, I have no idea... Rocker arms removed: Rocker arms themselves: Another shot that might be clearer: So at this point I don't know what's going to happen. I sent he pics to MSA's warranty department and now I'm just waiting to hear back. Hopefully tonight. Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted August 8, 2007 Administrators Share Posted August 8, 2007 Naviathan, The pictures aren’t really clear, but using Photoshop I was able to brighten this one up a little. I am not going to say that this is 100% the reason for your failure, but the pictures do suggest that improper wipe pattern is mostly responsible for your cam failure, though the soft cam core could also be partially to blame as well. Without seeing the entire head and all the parts in person to perform a formal failure analyses, the photos do strongly suggest that the wipe pattern is completely wrong with the cam wiping off the back side of the rockers which would cause the immediate failure. Your rockers have such a large shadow towards the tip with no shadow at the pivot end, indicating the installed lash pads are way to short. The shadow should be much smaller and be evident on both ends of the wiping surface like the picture below. A performance cam will have much less "shadowing" due to the more aggressive lobe profile. Your picture clearly shows the wipe pattern to be biased WAY too far back. Your wipe pattern; Proper wipe pattern from a stock cam… Proper wipe pattern, aggressive performance cam. As for the dual oiling, that is a totally acceptable mode of oiling the L-series cam. Generally, the oil restrictor in the block is opened to .100†and can be opened up as much as .125†MAX, along with a Turbo pump to help increases oil flow to the head without reducing pressure in the block. As TimZ stated, NEVER remove the oil restrictor in the block as that will starve the bottom end of adequate oil pressure. For those skeptics of the dual cam oiling method, measure the oil hole in the cam lobes of an internally oiled cam, calculate the open area of those 12 holes. Now calculate the oil restrictor hole in the block. Adding the spray bar isn’t going to reduce any appreciable oil flow to the rocker/lobe interface. If anything, it helps put the oil more precisely at that intersection between the cam lobe and rocker surface as some lobes, especially on the OE cams, have some lobes with the oil hole at the base of the closing ramp. Any how, sorry Naviathan, but the evidence thus far is weighting heavily towards improper wipe pattern, i.e. wrong lash pads. Quote Link to comment Share on other sites More sharing options...
naviathan Posted August 9, 2007 Author Share Posted August 9, 2007 I know. I don't get it either, I checked the wipe pattern and I had a small shadow at the bottom edge and a slightly larger shadow at the top edge. I figured being that it was still on the pad all would be well. As I said before I know they weren't perfectly centered, but they appeared to be good to go. I guess next time I'll have to make damned sure they are perfectly centered. I still haven't heard from MSA, but I figure I know what they're response will be. I guess it's time to start cam shopping again. Any suggestions? I'm thinking a regrind this time would be cheaper and last longer. Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted August 9, 2007 Administrators Share Posted August 9, 2007 Having at least “some†shadow on both ends is a good sign and the cam should've gone on to live a long happy life. Sounds like a regound NISSAN cam might be in your future eh? Keep us posted on what MSA has to say. Quote Link to comment Share on other sites More sharing options...
spacecase70 Posted August 9, 2007 Share Posted August 9, 2007 hey_Braap_why_dont_you_set_him_up_with_a_cam_and_rocker_set,__ sorry_broken_spacebar_on_keyboard Quote Link to comment Share on other sites More sharing options...
speeder Posted August 9, 2007 Share Posted August 9, 2007 There is no steel in existence that will not grind down when you run it over a 90 degree steel edge at over 200lbs of spring pressure.... I totally agree with the bad wipe pattern (lash pad selection) assessment. Iskendarian has long experience in L motor cams, and has some really good turbo grinds. Quote Link to comment Share on other sites More sharing options...
ziggy408 Posted August 9, 2007 Share Posted August 9, 2007 That was my thought. For the extremely short amount of time the car was running while I was trying to tune my MS-II it couldn't have done that much damage unless the metal was poor in the first place. If MSA decides to send me a new cam they had better send the block off plates this time like they were suppose to last time. I don't really like having the spray bar in there anyway. It gets in the way a lot. Still no word from them as of yet. I hope they call me back soon. I really need to get this resolved if nothing else for piece of mind. im pulling out my schneider stage 2 cam and putting in my old cam your more than welcome to it. Quote Link to comment Share on other sites More sharing options...
naviathan Posted August 9, 2007 Author Share Posted August 9, 2007 Ziggy, you're awesome. Just let me know what you want. What head do you have your cam in? Quote Link to comment Share on other sites More sharing options...
aarang Posted August 9, 2007 Share Posted August 9, 2007 Also on another note, Delta recommended to me that I use any diesel engine oil with this type of cam. I know there are a few threads that discuss this with the Zinc issue in newer oils. They brought this up without me even mentioning it! I am using Chevron DELO 15W- 40 now with no problems so far. Aaron Quote Link to comment Share on other sites More sharing options...
naviathan Posted August 9, 2007 Author Share Posted August 9, 2007 That was the biggest thing MSA brought up was the type of oil I use. I understand the whole zinc issue. I've read the numerous posts on it and I honestly think they need to come up with a zinc additive for older vehicles. Quote Link to comment Share on other sites More sharing options...
naviathan Posted August 9, 2007 Author Share Posted August 9, 2007 Just a quick question for BRAAP, what would have caused this dug out groove or indention that's only on the two rockers that were on the worn lobes? I know it's hard to see so I circled the spots that are worn. It's not like it's a slight groove either, it's really dug out. Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted August 9, 2007 Share Posted August 9, 2007 Wouldn't the wipe pattern shift as the lobe wore out, hiding evidence of the original wipe pattern? Or does the wipe pattern decrease in size as the lobe wears and decreases in lift. Quote Link to comment Share on other sites More sharing options...
naviathan Posted August 9, 2007 Author Share Posted August 9, 2007 Good question. The lobe that was on the rocker on the right is completely flat on the nose, the middle is worn down narrow, but still round and the left one is perfectly fine. Something isn't making any sense here. Quote Link to comment Share on other sites More sharing options...
ziggy408 Posted August 9, 2007 Share Posted August 9, 2007 Ziggy, you're awesome. Just let me know what you want. What head do you have your cam in? its in the p90 soild lifter head. im going to just use my old head with every thing in it. its also a p90 my old engine ran really good and strong the cam really came alive as soon as you nailed it. so i got to pull it off my old block anyway hopefully this weekend!!!!!! i dont have any use for it. just offer me what ever for it and its yours Quote Link to comment Share on other sites More sharing options...
naviathan Posted August 9, 2007 Author Share Posted August 9, 2007 Wait, you have a turbo don't you? Quote Link to comment Share on other sites More sharing options...
ziggy408 Posted August 9, 2007 Share Posted August 9, 2007 Wait, you have a turbo don't you? yeah stock tho... why wats up Quote Link to comment Share on other sites More sharing options...
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