LT1 Head question/problem
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From: The Stanley Keg TEXAS
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LT1 Head question/problem
This is for my Firebird, but since it shares the LT1 powerplant, I figured I'd ask here.
Heres some background. I have 1.6 Crane Golds installed (3 years) and they don't feel loose....BUT they sound like they want to come out from under the valve cover. Happens right on start up after the engine has cooled. Sounds like rocks (really small boulders) rattling in a can. After about 1 minute of idle the sound subsides, but is still slightly present.
I've removed the valve cover and let the engine idle but nothing was wobbling as bad as the sound would lead you to believe.
What does a dropped lifter sound like?
So I did this after getting feedback on a dropped lifter:
Well I replaced all 8 lifters on the drivers side but I still have a loud tick/clank that goes away after about 1 minute of idle. A friend and LT1 knowlegleable guru helped and we set all 4 rockers up like we are supposed to. None of the springs looked bad. So I'm not sure what to do next. The sound is coming from the head. Maybe one of the valve guides is week and the head expands the metal causing it to be ok? Any other ideas? Anyone know how much a "valve job" costs? Or does anyone have a LT1 driver's side head laying around?
Rich
Heres some background. I have 1.6 Crane Golds installed (3 years) and they don't feel loose....BUT they sound like they want to come out from under the valve cover. Happens right on start up after the engine has cooled. Sounds like rocks (really small boulders) rattling in a can. After about 1 minute of idle the sound subsides, but is still slightly present.
I've removed the valve cover and let the engine idle but nothing was wobbling as bad as the sound would lead you to believe.
What does a dropped lifter sound like?
So I did this after getting feedback on a dropped lifter:
Well I replaced all 8 lifters on the drivers side but I still have a loud tick/clank that goes away after about 1 minute of idle. A friend and LT1 knowlegleable guru helped and we set all 4 rockers up like we are supposed to. None of the springs looked bad. So I'm not sure what to do next. The sound is coming from the head. Maybe one of the valve guides is week and the head expands the metal causing it to be ok? Any other ideas? Anyone know how much a "valve job" costs? Or does anyone have a LT1 driver's side head laying around?
Rich
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Re: LT1 Head question/problem (Richard Thomas)
I had a similar problem on my L98. I set the preload with the engine running, and hot. I went another 1/4 turn and it went away. If you can run it with the valve covers off using the clips to prevent the oil from going everywhere, I'd suggest trying that with it cold to see if you can at least isolate which valve it is. Also, are there and clearance problems with the RR and the drip tabs? i've seen them things get chewed up by a set of RR.
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From: The Stanley Keg TEXAS
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Re: LT1 Head question/problem (Dr. Evil)
The rockers have been on for about 70K miles. The problem/sound just started about 1 week ago, so I don't think it's a clearance problem. I may try to re-adjust and see if I can isolate which cylinder is having the problem.
Thanks,
Rich
Thanks,
Rich
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Re: LT1 Head question/problem (Richard Thomas)
You said you've had these rockers for about 3 years.
I think crane has changed the crane gold lineup at some point in their production history. A friend of mine has some old ones that he swears are crane golds and they are about to fly apart now. I believe that crane redesigned their rockers and came up with the new crane golds which are actually gold and see to work very well. The old style looks like what is now sold as crane energizer rockers. If this is true of course. It's possible that his never were crane golds to begin with.
In any case his are silver and look like this
They are coming apart and I wouldn't trust them as far as I can throw them.
Mine look like this and have performed perfectly so far
I think crane has changed the crane gold lineup at some point in their production history. A friend of mine has some old ones that he swears are crane golds and they are about to fly apart now. I believe that crane redesigned their rockers and came up with the new crane golds which are actually gold and see to work very well. The old style looks like what is now sold as crane energizer rockers. If this is true of course. It's possible that his never were crane golds to begin with.
In any case his are silver and look like this
They are coming apart and I wouldn't trust them as far as I can throw them.
Mine look like this and have performed perfectly so far
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From: The Stanley Keg TEXAS
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Re: LT1 Head question/problem (Nathan Plemons)
Well, I went out at lunch to look over the exhaust manifold and started counting bolts. When I got to the rear, I was one short. Had a buddy come by and we cranked the car. He immediately pointed out that I had an exhaust leak. Yep, felt back there and felt the air.
Guess I should have kept it simple from the start. Oh well, I got 1/2 of a tune up sort of, and 8 used but probably good lifters sitting in my garage.
Rich
[Modified by Richard Thomas, 1:47 PM 2/18/2003]
Guess I should have kept it simple from the start. Oh well, I got 1/2 of a tune up sort of, and 8 used but probably good lifters sitting in my garage.
Rich
[Modified by Richard Thomas, 1:47 PM 2/18/2003]
