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Thread: No oil to rockers

  1. #1
    Join Date
    Dec 2011
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    lockport il
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    8

    No oil to rockers

    I really hope someone can shed some light on this situation for me. I just got done rebuilding a vortec 5.7 and have no oil pumping up to my rocker arms. Here's a quick run down on work involved. The block cam out of a 91 K3500. It's a 4 bolt main block. I had the local machine shop (very good, highly used in the racing community here) hot tank, magnaflux, line hone, bore cylinders .030 over, retrofit for hydraulic roller cam, and clearance block for stroker crank. Also installed new cam bearings and freeze plugs. I installed scat forged steel crank (1 piece seal), h-beam rods, and speed pro moly graphite coated pistons. I had shop balance rotating assembly and installed everything myself. I used all felpro gaskets and I blueprinted the entire engine. Every oil clearance was checked and was great. Topped off with edelbrock e-tec aluminum heads, and am running a comp cam. I disassembled roller lifters out of my 99 5.7 and cleaned and checked em all. I put on comp cams gold 1.5 full roller rocker arms and measured for push rods. They ended up being stock length at 7.200" so I got a set of comp cam magnum pushrods. After installing engine and priming oil pump it started right up. After about 4 minutes of run time I heard a slight knock. After locating knock and removing drivers side valve cover I found lifter to be collapsed. They soaked in oil for 2 months prior to going in and I also primed them in oil and they worked fine. That's when I noticed that the inside of valve cover had no signs of oil pumping to rockers. I started engine again with valve cover off and no oil coming up push rods. To me this is a sign of bad cam bearing or not lined up with oil hole in block. I know bearings are brand new and I know oil clearance is good. Anyone have suggestions as to what else could cause this? Any good ways to check this beyond pulling engine back out and removing cam? There are no oil leaks. Oil level is perfect and I show 65 psi on gauge. It's a brand new pressure sender and I checked with a manual gauge. (same results) I did put a meiling hi volume oil pump in there so that number don't seem to be that high to me considering everything is brand new. Please help.

  2. #2
    Join Date
    Jan 2012
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    229
    Sounds like cam bearings are rotated where the oil hole doesnt line up.

  3. #3
    Join Date
    Dec 2011
    Location
    lockport il
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    Ya thanks a lot cottontop. That's not what I wanted to hear. But I have to agree with you. But I'm wondering if that rear cam bearing is the passage that feeds the rest of the bearings and the lifters. If that's the case it's just that one bearing. If it was lets say the center bearing I would still have oil up to the rockers correct? This just really pisses me off that this shop has always been good and this one time they mess up and ruin my weekend! Thanks for the bad news that I was pretty sure was coming.

  4. #4
    Join Date
    Jan 2012
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    229
    Quote Originally Posted by snowbound98 View Post
    Ya thanks a lot cottontop. That's not what I wanted to hear. But I have to agree with you. But I'm wondering if that rear cam bearing is the passage that feeds the rest of the bearings and the lifters. If that's the case it's just that one bearing. If it was lets say the center bearing I would still have oil up to the rockers correct? This just really pisses me off that this shop has always been good and this one time they mess up and ruin my weekend! Thanks for the bad news that I was pretty sure was coming.
    Ive saw weird things with sbc's. Once me and my buddy changed heads on his iroc. We had it back together and were adjusting rocker arms and it hit us that we werent getting oil sprayed all over us so we shut it down. Before i killed it i checked oil pressure and had 40 psi. After scratching our heads a minute he wanted to tey again. Immediate upon startup oil was spraying all over me from the rocker arms. Motor still strong today dont know what happened

  5. #5
    Join Date
    Dec 2011
    Location
    lockport il
    Posts
    8
    Ya it's one of those things that I want to let it run but if I'm not getting oil to cam bearings, lifters or rockers I don't wanna take any more life off this engine. I have way too much money invested in it and it's a custom ground camshaft that is also getting starved. Believe me I wish I could get sprayed with oil and have that piece of mind. I'll look like an idiot if I tear it all down go back to shop and raise hell and everything is ok. I was just hoping someone had a good to tell me that I'm overlooking. But thanks for ur advise. I will definitely recheck before pulling it out again.

  6. #6
    Join Date
    Dec 2011
    Location
    lockport il
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    Ok so here's an update. I let the engine run again and still nothing. I called the machine shop and told them what was going on and they said that maybe I don't have the proper preload on the lifters and its causing them not to pump oil up. I kinda got a little upset and told them that I'm not an idiot and I have em adjust right. I tried 1/4-3/4 turn of preload and still nothing. He went on to explain that some LS engines take 1 1/4 turn of preload. So I explained to him that it's a vortec 350 so I don't care what an LS uses for preload. I hear his tech in the background saying that maybe my lifter bores are trashed and it's dumping off. So I told him that no that's not it cuz they were tight and slowly slid down when I installed them. Then he asks me how I primed the oil system. I was getting a little pissed that he's talking to me like I'm an idiot. I'm an ASE certified technician and I know what I'm doing so I explained to him not so kindly that I prime the system the same way he does. I inserted my oil priming tool and spun it til I saw 55lbs of pressure and then kept going for a good full minute. Then after all that and me getting pissed he tells me that there's no way the cam bearing is causing this cuz the bearings they used have the groove all the way around it on the back side of the bearing so even if they covered the hole it would still get there. So I was like then why couldn't u tell me this in the first place and I wouldnt have been talking to you this long. After getting that news I removed the intake and distributor and the front rocker, push rod, and lifter. Primed the system again and did see oil in lifter bore. Good news! So I primed lifter that was collapsed and it came right back up and reinstalled everything. Fired it up again but this time I let it run for about 6 minutes knowing that cam and everything else was getting good pressure. At that 6 min mark I started to see a little oil working up to rear rockers so I raised idle a bit and sure enough the lifters started pumping. Thank god! So now it runs great sounds good and been driving past 2 days. I have never built an engine and had this problem before this one. I guess all I can do is chaulk it up to a good lesson learned. I just hope maybe someone reading this can learn from my mistake and be a little more patient then I was. Cottontop was correct. I needed to wait for it to come around. Good call there cottontop. But when u got ur hard earned money sittin there and u think it's rubbing metal to metal it's easy to get paranoid and think the worst.

  7. #7
    Join Date
    Jan 2012
    Posts
    229
    Im glad to hear everything worked out. Im with you its hard do something like that when your hard earned money is the line. I applaud the way you approached it though.

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