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Discussion Starter #1 (Edited)
Help with a rocker question. As you can see in the pic this one is severely overheated. The pivot wore out and the rocker came off the valve. It's a new engine, small block Chevy 383. I've built my share of engines, but this is my first experience using a roller cam (hydraulic). I broke the engine in with a single set of single valve springs that were on the heads, since they only had about 20 hours on them. I know rollers really don't require a break in like a traditional flat tappet but since springs are easy to change on a small block I wasn't taking any chances. Ran it for an hour or so in the boat (no driveshaft to the jet) and then took it for a spin in the local lake to work out any bugs. Didn't hammer on it too much since I didn't want to float any valve and the lake is pretty small anyway, but I got the RPM's up a few times. So I changed the springs to a dual set, they had more pressure than the recommended ones since the ones called for wouldn't fit the World Heads without removal and machining. But not much more, only about 20 #'s, ended up being 155 closed and about 340 open, I don't have my build notes with me but those are the numbers I remember. And I've seen different companies call for similar pressures for less cam. It's not a big cam only .520 lift. Those rockers were from the old engine, worked fine with the single springs during the break in and the first outing, and when I changed the springs they still looked normal. My question is "Did I just commit a rookie mistake?" When you start dealing with those kind of pressure does that become full roller rocker territory? Is that ball assembly just not up to the task? A few of the others look overheated also. I don't think it's a lubrication problem, I have 30 psi idling and 60 cruising, and the ball ends of the pushrod and the seat of the rocker don't show any signs of galling and I can't catch a fingernail on any part of the ball if I spin the pushrod but I will look for other signs if you can point me in the right direction. That damage took about 1/2 hour of being on the river with lots of full throttle blasts although it only turns the impeller 5K. So if I am going to need to step up to a set of rollers in addition to any other problems you might have insight to, which are going to be the best choice, aluminum or stainless? Thanks in advance for any help, I'd like to be back on the lake sooner than later.
 

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Discussion Starter #2
The balls are grooved and they are Comp rockers. Used 15-40 Delo for breakin, changed it and went to the lake, changed it again to Mobil 1 before the fateful river run.
 

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steelcomp was here
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"Did I just commit a rookie mistake?"
Yup. :D
340 is way too much for stock stamped rockers, even the slotted ball, high perf ones, IMO. A set of rollers is so inexpensive these days. You'll need some EOS these days with anything that has a flat tappet or ball fulcrum like that. Just not enough zinc in anything any more. That's the main reason it failed. High spring pressure and no lubricant in the lubricant.:)sphss I think you could back down a bit on the spring pressure as well, especially if you're only turning 5000. You might even pick up a hun rpm.
AFA rockers, aluminum rollers would be fine here. Crane, Sharp, Scorpion, etc. Check with Competition Products and you might get a deal on a set of Millers. Stainless would even be nicer if you want to spend the $$.
If you;re not running any kind of performance oil pan, you might consider one. Not saying it was your problem, just a suggestion to help prevent this kind of thing in the future to other more expensive parts.;)
 

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Discussion Starter #4
Thanks for the fast reply, I have an 8 quart pan and a Melling select pump. I run 6 in the pan and the one in the filter and the gauge never drops off like its running out, and I have both the electric gauge in the dash and a mechanical one on the engine. I tried to do it right but I'm still learning after all these years. I wanted to run less spring but the guide boss on the Sportsman heads is pretty big so that limits my choices for dual springs. Is a dual spring a necessity, or is a single spring with the right specs acceptable? Never occured to me about the lack of zinc on the top end.
 

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steelcomp was here
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Thanks for the fast reply, I have an 8 quart pan and a Melling select pump. I run 6 in the pan and the one in the filter and the gauge never drops off like its running out, and I have both the electric gauge in the dash and a mechanical one on the engine. I tried to do it right but I'm still learning after all these years. I wanted to run less spring but the guide boss on the Sportsman heads is pretty big so that limits my choices for dual springs. Is a dual spring a necessity, or is a single spring with the right specs acceptable? Never occured to me about the lack of zinc on the top end.
Pan sounds fine. Depending on installed height, you might be able to come up with a single/damper spring combo that'll work. Maybe CStraub wil chime in here.
 
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For what it's worth, I did the same thing to a set of Comp Cams stamped roller rockers about a year ago. I never did find out what was wrong and replaced them with some good aluminum rollers and no problems.
 

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Gee, Does blue metal mean anything to any body???? This would be a clue Lack of oil??? M


I guess we need some more clue's ol' guy??? :)sphss

I would agree that a lack of oil could do this, but the pushrod seats and ends look good so I am guessing it is getting oil. If he is running top end restrictors the problem could be magnified, but with the rockers he's using and 150/340 spring pressure failure is only a matter of time regardless of the amount of oil on them.
I think Steel pointed him in the right direction........but what does he know! :D
 

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Can anybody post a bigger pic ? For some reason when I click on it it say's I don't have permission. It's not a red x and I'm logged in so I don't know what's up with that.
 

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During breakin a ball and pivot type rocker will build a ton of heat quickly. You state you ran the engine on the water with the breakin springs, what was the seat pressure on these springs? What is the pushrod length you used?
 

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So I changed the springs to a dual set, they had more pressure than the recommended ones since the ones called for wouldn't fit the World Heads without removal and machining. But not much more, only about 20 #'s, ended up being 155 closed and about 340 open, I don't have my build notes with me but those are the numbers I remember.
Comp's info states these rockers to be used with MAX of 350lbs open.
http://www.competitioncams.com/technical/Catalogs/106-07/268.pdf
To be honest, I've never used these, as I'm a stock rocker or typical full roller rocker person. No in betweens like these, cast full rockers, or what have you.

I agree that the bluing is of course over heating. The diagnosis falls on your lap though if it's an oiling issue, improper assembly issue, or rocker arm/ball issue itself.

When you do change rockers, the Scorpions are very good and one of the cheaper one's - other than the chinese poopo on E-Bay of course.

With all roller rockers, before installing, clean out all the assembly lube out of the bearings and tips. Then soak in motor oil. Many do not do this because of not realizing the assembly lube is more for corrosion protection and not that good of an actual lube.
 

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steelcomp was here
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I see that's not a stamped rocker, but one of Comp's Magnum rockers. Did these get a good coat of moly when installed new?
No one ever seems to tell anyone when they're selling these that Comp says not to exceed 350# with these rockers. It's written in the catalogues, but unless they've changed things, you won't find it on any of the packaging. You were right on the limit.
 

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steelcomp was here
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CFM beat me to the point...except to say I think these are a good alternative in many applications. I've used them on SB Fords many times with no issues. It sounds like you had them broken in so my guess is that combined with going to M1, and the excessive spring pressure, you just exceeded their design limit.
One more thing to note...I've seen them discolored before at the base, but the ball and seat were still fine. No galling or metal xfer of any kind, and still good surface integrity. This was using Valvoline racing oil, though. They had about 25-30K mi on them in a street/ off road truck that got it's share of abuse. I came to the conclusion that they were geting hot, but not to the point of destruction. This was with 300# springs (which is what they used to say was the limit on these rockers). Checked them from time to time and never any failure.
 

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Discussion Starter #15 (Edited)
Thanks, very informative you guys are great. They were used previously so were well broken in, I used them because I had them and they had worked flawlessly in the boat on my previous engine up to that point, and there was nothing srong with it except that I wanted more power. I had oil pumping out of the push rods because I checked when I primed the engine with a drill, I will do that again just make sure nothing got clogged, I also had the covers off after the initial firing and all the rockers had about the same amount of oil in the fulcrum area. Original springs were 110 at closed heigt and 280 open, push rods were the stock length 7.2, they're comp 7808, it made an even wear pattern with some Prussian Blue on the tip of the valve when I checked, wasn't biased toward either side, not that I can see microns. A set of rollers are going to be coming my way, again I appreciate the advice, if anyone is ever in Redondo and needs a place to crash for the evening or a beer I'm happy to oblige.
GB
 

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I guess we need some more clue's ol' guy??? :)sphss

I would agree that a lack of oil could do this, but the pushrod seats and ends look good so I am guessing it is getting oil. If he is running top end restrictors the problem could be magnified, but with the rockers he's using and 150/340 spring pressure failure is only a matter of time regardless of the amount of oil on them.
I think Steel pointed him in the right direction........but what does he know! :D
When dealing with a failure like this, let's not loose focus... Steel was dead on; when saying that with high spring pressure there was not enough lube in the oil, or lubrication properties in the oil. There was plenty of oil, as evidenced by the push rod tips not having contact stress fatigue, or galling. But due to excessive force of the spring, which was smashing all the oil out of the ball (the grooves couldn't hold enough lube after the heat set in) that this condition rapidly went from bad to worse, and this is were we see INSUFICIENT lube which is totaly different from lack of lube which means, no oil. insuficient lube means you can still see the heat signs when the rocker and ball have oil but the lube properties are not allowed to work due to diminished film thickness from too much spring pressure pushing the oil out, and the oil that is there does not have enough lube to work... This is where you see the black color from the oil that is there coking, or cooking into the metal. Lack of oil you will see much more temper colors (blues and straws) accompaning the black. Sorry for the long winded response: Back off on the spring pressure, and get the very best oil you and buy, that should take care of it..... $.02
STEVE
 

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I guess we need some more clue's ol' guy??? :)sphss

I would agree that a lack of oil could do this, but the pushrod seats and ends look good so I am guessing it is getting oil. If he is running top end restrictors the problem could be magnified, but with the rockers he's using and 150/340 spring pressure failure is only a matter of time regardless of the amount of oil on them.
I think Steel pointed him in the right direction........but what does he know! :D
Hey Warp, Didn't mean to ruffle feathers but if the push-rod tips look good but the ball and fulcrum are getting that hot it could be valve adjust. I don't know if you have ever adjusted valves with covers off and motor running you will notice that at proper adjust the oil will squirt pretty good. Take them down another quarter turn and the oil flow is hampered. Which COULD explain the p/r tips looking good but the ball and rocker are running dry. IMO M
 

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Or maybe the oil drippers as found on OE valve covers would have helped. :D

Either way, with these springs psi's and a normal performance boater driving, I'll take a better rocker any day of the weak.

OG - why do you suppose you get less oil thru pushrods when 'a little too tight.'
 

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Steelcomp is right.

I did it myself once, last spring.
Motor was happy on the stock long slot stamped rockers to 5,000RPM for 3 years, synthetic oil.
Added the new nitrous system and on the first 5,400RPM blast, developed an exhaust pop. No other engine changes.
Found one rocker looked just like that, overheated. The added stress of the added 400 RPM was too much.

I simply asked for more than the rocker pivot system was up to delivering.

Replaced them with Comp Hy-Tech stainless rollers, no problems any more. Had to replace the studs for more length, my HT's have a seriously thick trunion.

Go roller rocker or go lighter springs.
 
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