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By Richard - 11 Years Ago
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Since I am paranoid after wiping the last cam and assorted lifters I just wanted to check. I read a Comp Cam breakin procedure. At the end the tech said if all your push rods are turning you are ok.
I painted a stripe on my pushrods, fired it after breakin and they all turn. Can I consider my valve train good to go. All the rockers push the springs down about the same but it is hard to measure. Tried using the tails on my calipers but had a hard time locating on the head surface. Drained the oil it looked ok ran a magnet through it no metal. Opened up the oil filter found some fine/powdered metal in the paper element.
Is there anything else I should look for.
Thanks
Richard
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By 2721955meteor - 11 Years Ago
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fines in the filter. check the oil supley to rockers.i see most rocker shafts are badley galled due to poor or no lubrication,which causes some cuttings, and eventually cam failures.other causes would be more serius re oil pump failure, rod or main brg isues. so look into the easey and most likeley first. good luck cliff
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By Richard - 11 Years Ago
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The rocker arm shafts are new with rockers installed by Rocker Arm Specialty 1.6 ratio. The oil pump puts out nearly 60 psi. Everything is new in the engine. It has 20 mins on it. To be on the safe side I put a heavy magnet on the fram filter canister. The amount of powered oily metal less than 1/4 teaspoon. I also had a flat heavy magnet on the bottom of the oilpan near the pick up. I tried to shove a small magnet in the oil drain hole but it just bumps up against the pick up.
My question is how do I know the lifters and cam are broken in. The push rods spin.
Would a compression check be a good guide. Like I said I am paranoid after the last run and pulling the engine to install the new Clay Smith Cam and new lifters.
Thanks again.
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By PF Arcand - 11 Years Ago
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Were you able to ascertain with reasonable certainty, what likely caused the 1st failure ?
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By Richard - 11 Years Ago
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Yes the engine sat for a long time after the build. I started it a number of times at low RPM never reving. My opinion is the break in procedure was not good.
I will be doing a compression test this afternoon, if everything is jake I will run it again but would sure like to confirm: If the push rods spin around does that mean the lifters are spining like they should after a correct break in.
I used Valvoline racing oil and Lucas zdpt
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By speedpro56 - 11 Years Ago
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compare valve lash between a couple runs to make sure the cam and lifters aren't going away.
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By Richard - 11 Years Ago
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Thanks Gary,
How much lash do you think will make a difference, and does't the break in process loosen up the lash.
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By RB - 11 Years Ago
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I think you are being a bit paranoid, although not without justification. The net is full of horror stories. If the lifters turn then you are almost certainly OK.. A little metal in the filter after break in is normal.. If you had a cam fail or in the process of failing you would find BIG variations in lash. Like .010 or more. I agree with Mummert. Cam failures, when they occur, are usually in the first few minutes of the break in
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By Richard - 11 Years Ago
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Well I had three over .015 so guess I maybe in the dog house again. Readjusted them ran it again push rods spin no other change in lash. Dumped the oil and filter, cut the filter and found some residue and got paranoid. Oil was valvoline VH1 straight 50. For what its worth I coated the cam with the moly lube provided with cam.
New oil is valvoline VH1 20-50 will get some zinc adder then run it up again.
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By charliemccraney - 11 Years Ago
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I think you mean VR1 rather than VH1 Valvoline VR1 has plenty of zinc right out of the bottle. Don't add any more.
I have never checked how my lash varies during the break in of new parts but it has usually settled down after a few drives. You have a lot going on with a new motor. The cam is breaking in with the lifters which are breaking in with the pushrods, which are breaking in with the rocker arms, which are breaking in with the valve stems, There will be variation in the begining. If you got through the initial break in and the adjuster screws are all adjusted approximately the same and not changing significantly, you're probably ok.
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By Ted - 11 Years Ago
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After twenty minutes of running, I typically look for no more than 0.002” variance in valve lash between the valves. While iron heads will not vary the lash much from cold to hot, the aluminum heads will grow approximately 0.007"-0.008" from cold to hot so that must be taken into account but the variance between valves should still be minimal. If I find an excessive amount of variance, then I take note of the valves in question and after running the engine some more (5 minutes tops), then recheck the valves. If there’s an additional increase in lash, then there’s a problem. Valve lash checks on my end are performed with the engine not running.
Here’s the link to the list of items that contributes to cam/lifter failure. Any one or a combination of these can cause a problem.
http://www.eatonbalancing.com/blog/2012/11/06/camshaft-and-lifter-failure-causes-2/
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By Richard - 11 Years Ago
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Thanks Ted,
Slept on it and am resolved to deal with the problem or lack there of what ever it takes. I'll run again today and see what happens.
Checking your list I see why failure happened the first time: Items 2,3,4.
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By 2721955meteor - 11 Years Ago
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i agree with charlie on the oil. if you have lubed the cam lobes with the cam suplyers stuff.. my aproach to startup is do not do it until you can put some miles on. at the very start pre lube the engine till oil is coming to the rockers,then use a mixture of oil and gas down the carb so the valve guids get some lube,make sure no water or oil leaks ,go for a drive and very the speed and drive for 30min you should be ok. after this re set the valves. again. if you start the car then leave it for months you ar increasing the ods for problem. i have a spare engine all built for my 57ranchero, i do not tighten the rockers down as why leave valve springs compressed. as well you want the molley cam grease on cam lobes and lifters for initial run in.Like others have noted you will get someparticles in the filter. breakin is a topic that has maney vews,you only know who is correct down the road. good luck
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By Richard - 11 Years Ago
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Thanks Meteor,
Pretty much did everything you suggested except oil and gas in the carb. Great idea by the way. Prepping for another stationery run in. New oil, filter, and using an old dizzy drive to push the oil through the system. If I don't get any more loose rockers then I will drive it.
Thanks for all of your support.
By the way:
All kinds of spooky stuff on the internet about this topic so its not just a Y block issue. Most blame the metallurgy or lack of proper heat treating to cam and lifters. I have no idea but regardless of the out come I will push on. If I have to rebuild I will approach the break in with the center valve springs removed. After all we cannot go to hydraulic lifters like all the others. Some of the cam grinders offer nitride for an extra hundred bucks. Seems odd to me that option isn't standard on all solid lifter applications considering the consequences ,. Regardless too late for philosophy have to deal with the problems at hand.
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By Cliff - 10 Years Ago
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Hi, any update?
Cliff
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By Richard - 10 Years Ago
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Update: Ran it again 2000-3000 RPM Engine sounds great. Drained the oil, dropped the pan, cleaned out some powdered iron oil not much really. Inspected the cam and lifters, they look fine no wear. Cylinder walls look good.
Push rods spin as they should, so I think I will be on the road shortly for 50 mile run.
Thanks for all the advice.
Pictures to follow.
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By John Mummert - 10 Years Ago
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Richard, sounds like you are okay this time. I had 1 cam failure years ago that I was fairly certain was caused by lifters that weren't heat treated correctly. Some lifters from another source failed because they were made of junk material that was heat treated to the correct hardness but the substrate was soft and wouldn't support the hard surface.
With regard to cams, I think the most common problem is lack of taper. In this case the lifter will only hit in the center and not rotate. I have seen 2 failures that I believed were caused by lack of taper.
One of the recent problems we have seen or heard about is poorly made rocker adjusters. The ones in question look like Ford self locking adjusters but require a jamb nut. The surface tests harder than original Ford adjusters but the underlying material is soft. I have seen these totally worn out in 50 miles.
Probably the most valuable tools to use during cam break-in are your ears! If at all possible, have mufflers on the test stand, dyno or however you have it mounted. If you hear any clatter of ticking that seems to be getting louder, shut it off. Check the lash. Look for metal in the drain back recesses near the rocker arms. According to Harvey Crane, if the cam is going to fail it happens in the first 2-3 minutes. Don't force the 20 minute break-in on an engine that is getting louder and louder. I like to have an open breather on the engine. Slight wisps of smoke are normal. A steady stream of smoke from the breather is a sign the engine is burning oil internally. This indicates hot metal. Not a good sign.
I had an engine on the stand that started to get a louder ticking sound after a few minutes. I found a rocker with .015" more lash than normal. Because the wear on the cam was slight the cam grinder was able to grind the one lobe and with a new lifter in place the engine was saved. Had I forced the break-in, the lobe would have gone flat and all the metal would have gone through the engine.
I have shut off quite a few engines before the 20 minute period was up and never had one fail upon restart.
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By PF Arcand - 10 Years Ago
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Richard: Just a question? Noticed in your earlier posts, that you said you started the new engine using straight 50 W oil . Was that recommended by someone? It isn't usual to do that...
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By Richard - 10 Years Ago
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Yes I used straight 50. Guess I messed that up too. Regardless, its got 20/50 now
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By 2721955meteor - 10 Years Ago
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My thoughts are to use 10-30 and do not change oil as the cam lube you instaled at assembly should stay in for at least 500 miles. A filter change after a short drive will tell you if there is a problem. and there will be stuff in the filter, even in a new engine. The lighter oil will ensure lots of early splash to lube cam.
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