Lifter question
Thread Starter
Melting Slicks
Joined: Jul 2009
Posts: 3,264
Likes: 3
From: Vero Beach FL
Lifter question
Engine guys,
I am replacing the heads on my 350 in the next few weeks with a pair that have been reconditioned. My first question is how can you tell if a lifter is bad? If I replace them with new ones will it cause wear on the existing cam lobes? I am experiencing some lifter noise now perhaps it’s in the valve lash not really sure. I hate to find out after I put it back together that there is a problem with a lifter.
Thanks, Scott
I am replacing the heads on my 350 in the next few weeks with a pair that have been reconditioned. My first question is how can you tell if a lifter is bad? If I replace them with new ones will it cause wear on the existing cam lobes? I am experiencing some lifter noise now perhaps it’s in the valve lash not really sure. I hate to find out after I put it back together that there is a problem with a lifter.
Thanks, Scott
Drifting
Joined: Dec 2002
Posts: 1,946
Likes: 28
From: Long Beach CA
Look at the wear on the current lifters and the cam. If they're looking good, the cam lobes are flat and the faces of the lifters are convex, then there should be no problem with new lifters on the existing cam.
However, since the car is still together and running, you'd be better off to determine what is causing the noise. If it's just an adjusment, you can save yourself the expense of new lifters.
However, since the car is still together and running, you'd be better off to determine what is causing the noise. If it's just an adjusment, you can save yourself the expense of new lifters.
Thread Starter
Melting Slicks
Joined: Jul 2009
Posts: 3,264
Likes: 3
From: Vero Beach FL
Hello LB
I have adjusted the lash on the lifters but not to say that the lifter are all "loaded" properly. I have an old valve cover that I am going to cut the top out of so I can adjust the rockers with the engine running.
How would I inspect that cam lobes without removing the cam? By removing the lifters and looking through there?
Thanks, Scott
I have adjusted the lash on the lifters but not to say that the lifter are all "loaded" properly. I have an old valve cover that I am going to cut the top out of so I can adjust the rockers with the engine running.
How would I inspect that cam lobes without removing the cam? By removing the lifters and looking through there?
Thanks, Scott
Race Director
Joined: Mar 2009
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From: Canada's capital
2020 Corvette of the Year Finalist (appearance mods)
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Ya, you should be able to see the cam lobes down the lifter bore, and side ways through the galleys. Make darn sure you don't get the lifters mixed up in the wrong holes, otherwise, they're toast, and breaking in new lifters on a used cam isn't the best. Check for wear, and PITS in both the cam and lifters, as well as the rest of the wear points like the ends of the pushrods, rockers, *****, etc.
Drifting
Joined: Mar 2011
Posts: 1,271
Likes: 1
From: PA
Check your stamped rockers for wear. A more likely culprit if your cam looks good and has been fed a nice ZDDP diet. Maybe a great time to upgrade to roller tip rockers and poly locks when you install the new heads. How many miles on the valve train ?
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
I just replaced my intake manifold. Upon removing the old one, I found a clip from a lifter came off. I replaced all my lifters with new ones. Then placed the new manifold on. You can place new lifters on a old cam. But you can't place a new cam with old lifters.
Thread Starter
Melting Slicks
Joined: Jul 2009
Posts: 3,264
Likes: 3
From: Vero Beach FL
Thanks guys,
I may have found my problem or at least the noise. I cut the top off one of my old valve covers so I could set the valve lash with the engine running. Well when I put the old valve cover on the noise stopped. One of the rockers in the center is tapping the valve covers these are high valve cover and not cheap ones. Any thought on this?
I may have found my problem or at least the noise. I cut the top off one of my old valve covers so I could set the valve lash with the engine running. Well when I put the old valve cover on the noise stopped. One of the rockers in the center is tapping the valve covers these are high valve cover and not cheap ones. Any thought on this?
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Advanced
Joined: Jul 2011
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From: Toledo Ohio
Thanks guys,
I may have found my problem or at least the noise. I cut the top off one of my old valve covers so I could set the valve lash with the engine running. Well when I put the old valve cover on the noise stopped. One of the rockers in the center is tapping the valve covers these are high valve cover and not cheap ones. Any thought on this?
I may have found my problem or at least the noise. I cut the top off one of my old valve covers so I could set the valve lash with the engine running. Well when I put the old valve cover on the noise stopped. One of the rockers in the center is tapping the valve covers these are high valve cover and not cheap ones. Any thought on this?
Thread Starter
Melting Slicks
Joined: Jul 2009
Posts: 3,264
Likes: 3
From: Vero Beach FL
Scott
Thread Starter
Melting Slicks
Joined: Jul 2009
Posts: 3,264
Likes: 3
From: Vero Beach FL
The reason I am replacing the heads is I notice that some of the valve guide were really worn bad a few years ago when I had the heads off. At that point I was just trying to the thing to run so I could get it in and out of the garage while working on the body. Do you think worn guide could cause this?
Last edited by Roco71; Oct 26, 2011 at 08:34 PM.
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
What do have planned for heads now the lifter noise is fixed?
For the rocker noise it must be hitting a oil splash baffle or even the PCV itself inside the vlv cover - look for wear marks inside. Once u find out what its hitting u should be the one to make the call on the fix.
Are u going to still replace the heads? If the vlv guides are worn u should be using oil or at least smoking blue on engine start in the morning.
U need to do a compression test at least to determine health of the engine. A leak down test takes a little more time and equipment but will pinpoint any cylinder leakage/wear.
If u are going to do the crate motor R&R next year its hardly worth the effort to do a recam or R&R the heads. FYI i drove a 350 sb for nearly a year with one cylinder nearly 50 psi lower compression than the others and it drove fine for a DD.
Just my 2 cents is i would do compression and leakdown and diagnose before spending any money.
cardo0
Are u going to still replace the heads? If the vlv guides are worn u should be using oil or at least smoking blue on engine start in the morning.
U need to do a compression test at least to determine health of the engine. A leak down test takes a little more time and equipment but will pinpoint any cylinder leakage/wear.
If u are going to do the crate motor R&R next year its hardly worth the effort to do a recam or R&R the heads. FYI i drove a 350 sb for nearly a year with one cylinder nearly 50 psi lower compression than the others and it drove fine for a DD.
Just my 2 cents is i would do compression and leakdown and diagnose before spending any money.
cardo0
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Have those same covers with Jesels
Use a thicker valve cover gasket and youll be fine.
Mr Gasket makes them I believe. Those have oil drippers in them that can touch .
Use a thicker valve cover gasket and youll be fine.
Mr Gasket makes them I believe. Those have oil drippers in them that can touch .
Thread Starter
Melting Slicks
Joined: Jul 2009
Posts: 3,264
Likes: 3
From: Vero Beach FL
For the rocker noise it must be hitting a oil splash baffle or even the PCV itself inside the vlv cover - look for wear marks inside. Once u find out what its hitting u should be the one to make the call on the fix.
Are u going to still replace the heads? If the vlv guides are worn u should be using oil or at least smoking blue on engine start in the morning.
U need to do a compression test at least to determine health of the engine. A leak down test takes a little more time and equipment but will pinpoint any cylinder leakage/wear.
If u are going to do the crate motor R&R next year its hardly worth the effort to do a recam or R&R the heads. FYI i drove a 350 sb for nearly a year with one cylinder nearly 50 psi lower compression than the others and it drove fine for a DD.
Just my 2 cents is i would do compression and leakdown and diagnose before spending any money.
cardo0
Are u going to still replace the heads? If the vlv guides are worn u should be using oil or at least smoking blue on engine start in the morning.
U need to do a compression test at least to determine health of the engine. A leak down test takes a little more time and equipment but will pinpoint any cylinder leakage/wear.
If u are going to do the crate motor R&R next year its hardly worth the effort to do a recam or R&R the heads. FYI i drove a 350 sb for nearly a year with one cylinder nearly 50 psi lower compression than the others and it drove fine for a DD.
Just my 2 cents is i would do compression and leakdown and diagnose before spending any money.
cardo0
Cruisin, I will check into it,
1969 Ray, My friend said the same thing
Thanks
Team Owner
Joined: May 2001
Posts: 87,375
Likes: 1,593
From: Western NY
Personally, I think you would have been better off grinding a little off the valve cover.....the piece that does nothing more than contain the oil splash, rather than the piece that pivots against valve spring pressure on one side, and a hot valve on the other. But that's just me....
Thread Starter
Melting Slicks
Joined: Jul 2009
Posts: 3,264
Likes: 3
From: Vero Beach FL
Update
Well here's the update. I took my Dremel with sanding cylinder (mini drum) and sort of polished the back of the rocker arm. Then did the area on the valve cover were it was hitting, bolted it back up and the tapping sound is now gone.
Melting Slicks
Joined: Aug 2008
Posts: 2,200
Likes: 3
From: Lehigh county Pennsylvania
Imagine that...not a lifter problem after all. Will wonders never cease?