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Noisy rockers after rebuild---Oiling?
https://www.slantsix.org/forum/viewtopic.php?t=13204		 Page 1 of 1
Author:  rrither [ Mon May 30, 2005 6:09 pm ]
Post subject:  Noisy rockers after rebuild---Oiling?
I do not like the way it sounds, much noisier than prior to rebuild. There is oil up top, coming out all the rocker holes, but not near as much as prior to rebuild. I can, with the cover off, rev the engine up, and the amount of oil does not increase much, I could not do this prior to rebuild, there would be oil all over the place. I have pulled the rear head bolt and ran a small welding rod down the hole, I was able to get down as far as the cam, same from rocker to head bolt. When I crank it, oil shoots out each rotation with the rear rocker bolt removed. Oil pressure is just shy of 60 psi on the road, and around 40 psi at idle. The rocker shaft has the flat top- front, and holes at 4:00. I was very careful when dis-and re-assembling this. Shaft had plugs pulled and was hot tanked, as suggested.
I have adjusted the lash (.010 & .017 ) every way to Sunday, no change. The comp cam card (252) says the exhaust should be .012, as posted here nothing less than .016 allows a good idle.
I had the machine shop assemble the short block, I kick myself for not pulling the cam and checking the drilling, and bearing prior to putting the tin on......dumb, dumb, dumb. :cry:
Short of you good people suggesting something else to try, I am going to pull cam and check the drilling. I do not want to, but it sounds so bad to me, not the sound it should make.
Author:  sixty4dartgt [ Tue May 31, 2005 6:29 am ]
Post subject: 
I don't know what your motor problem is, but I ran my 252 Comp @ .10 amd .12 and had a good idle.
Maybe it's something with your carb?
Author:  Jeb [ Tue May 31, 2005 11:15 am ]
Post subject: 
You may have put the shaft on backwards, you know, the one that that the arms pivot on. I did it on my Duster and it rattled like crazy.
Author:  GTS225 [ Tue May 31, 2005 4:01 pm ]
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Ross.....before you pull the cam, try this; Put the welding rod down to the cam again, and VERY slowly turn the engine over by hand. I would think that the rod would drop down into the rear cam journal when everything got lined up. If it does, that should tell you something without having to pull the cam.

Roger
Author:  rrither [ Wed Jun 01, 2005 9:10 am ]
Post subject: 
Thanks all.
Been driving it, put about 200 miles on it. I was not too worried about driving it as there is some oil up top. Still no change. I have reset the lash to .010 & .012; the .012 gave the idle a bit of a rhythm, about 200 rpm up-down, still noisy. I will try to fish the wire through the cam, by turning as suggested, just to gather a bit more info so I make a educated decision about puling it apart again, or not.
It sure sounds like rocker noise, a stethoscope tells me I am in the right area.
I now wonder just how much oil should be up there. It is oiling, it squirted me good with the rear rocker bolt out when cranked over. One bit I am thinking about is, when the rocker was in the machine shop for cleaning, they "polished" the shaft, said it is a standard they practice, said it was to take the edges off the wear areas. I am thinking about cleaning up a spar assembly I have and installing it to see if it changes the noise level.
It just doesn’t sound right. Sounds like the $50. Datsun truck I thrashed in high school, I just can’t go there again.
Author:  SlantSixDan [ Wed Jun 01, 2005 10:14 am ]
Post subject: 
Quote:
Still no change.
Arrgh. Sounds like there'll be some disassembly and reworking involved.
Quote:
I have reset the lash to .010 & .012 the .012 gave the idle a bit of a rhythm, about 200 rpm up-down
As others have mentioned, 0.012" is too tight on the exhaust. The "rhythm" you got with this adjustment demonstrates that. You'll want to back this off.
Quote:
I now wonder just how much oil should be up there.
Your description of the amount of oiling you had before, with the old cam, sounds perfect. Your description of the reduced oiling you have now, with the new cam, sounds insufficient.
Quote:
when the rocker was in the machine shop for cleaning, they "polished" the shaft, said it is a standard they practice, said it was to take the edges off the wear areas.
Bah humbug. Those shafts do not need to be polished; there are no "edges on the wear areas" (the wear areas are visible 'cause they're...polished!). Take another look at the top end when the engine's running. If you see a great deal of oil just dripping down off the bottom of the rocker shaft, their polish job might have undersized the shaft.

You're reminding me of problems a local boardmember here in Ontario had with the Comp 252 cam.
Author:  rrither [ Wed Jun 01, 2005 1:13 pm ]
Post subject: 
Well, I picked up the gaskets at lunch, and I am planning on yanking the lump stick this Friday. I see the oil pump, lifters and A/C condenser being the challenging parts to move and remove. Any tips on resealing the cover to pan rubber? How about the lifters, that’s a long reach, will a hydraulic lifter remover work?
I am bummed, to say the least. I really hope I find the cam drilling off, as I can handle that in my shop. I like to put my finger on the cause, rather than guessing.

The exh lash will go back to .016
Author:  rrither [ Wed Jun 01, 2005 1:17 pm ]
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O-yea. There is not excessive oil leaking past the rocker to shaft area. It appears to be dripping down from above.
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