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I just got done installing a set of comp cams 1.6 magnum rockers and new comp cams pushrods. I was originally running the 1.5 GM rockers and stock pushrods.
I adjusted the rockers with 0 lash cold using a .002 feeler gauage and by checking the pushrod play against the rocker. When I found 0 lash I turned each nut 1/2 turn. It all went back together fine and I had no noise on stgart up or driving around for about 100 miles. I spent a few hundred miles driving very easy and then I took it up to 5,000 rpm, lost power and got a bad noise from the top end of the motor.
This motor has about 15,000 miles on it with no trouble, see my sig for what I have. ANyway, I pulled off the valve covers and the #7 cylinder intake rocker was just hanging there and the push rod
was sitting loose in the lifter. Then I looked at the exhaust side of #7 and the pushrod was GONE and the rocker was just hanging there. I inspected the nuts , they were tight and had not backed off, the rockers and balls looked fine, the valve stems looked fine.
So, I pulled off the intake and in the back of the lifter galley I found the missing pushrod bent bad, but not broken. The tips of both pushrods looked fine. WTF??? What did I do?
Anyone got any ideas? If I had just bent a push rod it would be easier to figure out, but the other pushrod somehow came
out of its pocket in the rocker and just sat there. How the **** does a pushrod fall into the rocker oil galley?!!!!!!!
I must be one dumb **** for this to happen.
Thanks for the help as always...........bob
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__________________ 91 camaro RS convert,GM crate 350 LT1 cam, 1.6 comp cams roller tipped rockers, edelbrock 6085 heads,9.5:1 comp, edelbrock TBI intake bored to 2", 90# injectors,454 TB, My own custom chip that I continue to modify, ramair dual snorkle cold air ,dual fan conversion, ultimate TBI mods,TBI spacer,SLP 1 5/8 headers,
3"cat back,SLP single 3" muffler,
T-5, centerforce 2 clutch( 1st one blew@4,000 miles), 3.42 torsen posi,alston SFC's,Global West LCA relocation brackets, edelbrock/ owner modified 2 point STB that allows ramair dual snorkel to clear.
Baer sport 12" front discs and PBR calipers. A little faster now, 14.26 @ 103.1 on streets on G-tech @ 6,000 foot altitude , car weight 3369# without driver and spare tire but lots of subwoffers. Now I am definitly gonna spray it........
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It's possible that the pushrod was lifted slightly during adjustment and was resting on the edge of the lifter instead of the center. When you adjusted it it would have felt fine but eventually slipped off the side of the lifter after running the motor for a while.
You have an LT1 cam and 1.6 ratio rockers, i would say you ran into coil bind. Replace the springs with the proper ones for your setup the stock ones are worthless.
__________________ LT1 headed LG4 305 beast! Comp Solid lifter XS-262-10S, 1.6 Roller Rockers, 10.2:1, Holley 4160 600cfm, modded Weiand 7502 intake to fit LT1 heads____ Custom cylinder head cooling. Weiand 8208 Short Water Pump____TH-350 3 series 3.73 with 2 series posi and spacer____ Hedman Hedders 1 5/8 headers and Y-pipe 3in Exhaust, Dynomax 3" Bullet muffler ____Moroso Ultra 40 Wires ACCEL HEI Super Coil ____Competition Engineering 3120 Bolt-on SFC's____Homemade: Wonderbar, solid tie rod sleeves, Aluminum LCA and Panhard Rod with spherical rod ends, alternator and PS bracket, Strut tower brace, and Decoupling torque arm with telescoping link.
3000lbs
"The liberty of a democracy is not safe if the people tolerate the growth of private power to a point where it becomes stronger than their democratic State itself. That, in its essence, is Fascism - ownership of government by an individual, by a group or by any controlling private power."
-FDR
"If this were a dictatorship, it'd be a heck of a lot easier, just so long as I'm the dictator."
-- President George W. Bush
During a photo-op with Congressional leaders on 12/18/2000.
Ok maybe not i just noticed that you have Edelbrock heads, not stock ones.
__________________ LT1 headed LG4 305 beast! Comp Solid lifter XS-262-10S, 1.6 Roller Rockers, 10.2:1, Holley 4160 600cfm, modded Weiand 7502 intake to fit LT1 heads____ Custom cylinder head cooling. Weiand 8208 Short Water Pump____TH-350 3 series 3.73 with 2 series posi and spacer____ Hedman Hedders 1 5/8 headers and Y-pipe 3in Exhaust, Dynomax 3" Bullet muffler ____Moroso Ultra 40 Wires ACCEL HEI Super Coil ____Competition Engineering 3120 Bolt-on SFC's____Homemade: Wonderbar, solid tie rod sleeves, Aluminum LCA and Panhard Rod with spherical rod ends, alternator and PS bracket, Strut tower brace, and Decoupling torque arm with telescoping link.
3000lbs
"The liberty of a democracy is not safe if the people tolerate the growth of private power to a point where it becomes stronger than their democratic State itself. That, in its essence, is Fascism - ownership of government by an individual, by a group or by any controlling private power."
-FDR
"If this were a dictatorship, it'd be a heck of a lot easier, just so long as I'm the dictator."
-- President George W. Bush
During a photo-op with Congressional leaders on 12/18/2000.
Ok, I figured out that I adjusted the valves for #7 out of sequence so I was way loose. What a dumb f****. So , get this, I re did the adjustment cold and noticed a little valve train noise so I adjusted them hot with the motor running. I loosened the nuts till I heard noise, tightened till it stopped and then gave it a quarter turn. Damn if I didn't have the same problem on #6 intake.
It started making noise, so I took off the cover and the nut is laying in the head, the rocker is hanging on the stud and the push rod is loose in the slot. WTF???WTF???
The nuts are new, the rockers are new, the balls are new the PR's are new, how can this happen when you do it right and valves are hot????
I had an extra new pushrod, ball and nut, (I always buy one or two extra cause I always manage to screw things up) and I readjusted all the valves hot, but gave them 1/2 turn after no noise and an 1/8 extra. Seems to be ok but I don't know if I am gonna keep having this problem. I am afraid to take it over 3,000 rpm.
The only other thing I can think of is edelbrock told me to use .100
longer push rods with the 6085 heads so I did. The old push rods were standard 7.2 with 1.5 rockers.
Any thoughts on this would be appreciated. I am stumped......................bob
PS the 1.6 RR made a BIG difference in performance. I think I under cammed this engine so the small difference in lift is a big help.
Just another argument for hot-lashing the valves with the engine running. An oil mess is a lot better than a valve train mess, and for $5 worth of deflector clips, you don't even have to have an oil mess.
__________________ Later,
Vader
- - - - - - - - - - - - - - - - - - "Everything should be made as simple as possible, and not one step simpler."
HITHERE DID adjust the valves the second time with the engine running and number six still backed off and and left the rocker hanging and the pushrod loose. HITHERE cannot figure it out!!!
The easiest way for me, is to run through all 16 of them as quickly as possible, and set them all to "zero lash"; then turn the engine off, and add the chosen preload, usually ½ turn. Doint it that way avoids additional unnecessary oil mess from waiting for the engine to recover from running terrible every time a valve gets preload added to it.
__________________ "So many Mustangs, so little time..."
there is no room on the stud to use a jam nut. The nuts are all turned down so there is only about 1/16 inch left on the stud. I am still thinking that edelbrock is wrong( what 's new) about using .100 longer pushrods with these heads. maybe that is causing the problem. Right now it is running fine after adjusting hot /engine running and using 5/8 turn after 0 lash. But I don't know whether that will solve the problem.
I used the clips from summit to reduce oil spill and they really helped , not much mess at all. For $10 they are worth it but I have a stock oil pump. May not help for hight flow pumps.
I am still looking for an answer as to why a new rocker nut would back all the way off after adjusting hot/running with 1/4 turn. It only took few miles and it came off. ................bob
Oil deflector clips are devices that clip over the oiling holes on rocker arms to keep oil from spraying all over while you hot-lash the valves.
I'm thinking that you may have a geometry problem as well, and that you should check for the correct push rod length and adjust as necessary. If you have no extra room for jamb nuts with the correct push rods, you may need to install top-locking nuts in place of the factory self-locking nuts.
__________________ Later,
Vader
- - - - - - - - - - - - - - - - - - "Everything should be made as simple as possible, and not one step simpler."
Vader, thanks for the comment. I will check into the top locking nuts. I didn't know they were available but I am gonna get some.
I think i will drive it for a while and then check for wear on the valve stems with the existing .100 longer PR's. I ran the engine with the stock lenght PR's for 15,000 miles with the stock 1.5 rockers and had no problem. I thought with the 1.6 rockers I had better take edelbrocks advice and go with the ones they recommended. thanks ...............bob
