loud valve train noise
Thread Starter
Instructor
Joined: Aug 2007
Posts: 140
Likes: 0
From: Erie Pa.
loud valve train noise
in my 72,( 350ci, 492 heads, mild cam) my rocker arms are crain roller tip rockers # p777,
I have adjusted my rockers but I still get a valve train noise, it doesn't sound like its hurting anything its just anoying. exsessive clatter is the only way i can explain.
is this normal with these roller tip rockers. previous owner said they are hydrolic lifters. Any input is welcome. thanks.
update, the noise sounds lower.
I have adjusted my rockers but I still get a valve train noise, it doesn't sound like its hurting anything its just anoying. exsessive clatter is the only way i can explain.
is this normal with these roller tip rockers. previous owner said they are hydrolic lifters. Any input is welcome. thanks.
update, the noise sounds lower.
Last edited by goldengoat2; Apr 21, 2013 at 12:17 PM. Reason: new info.
Le Mans Master
Joined: Feb 1999
Posts: 8,351
Likes: 75
From: Tampa Bay FL
I had excessive valvetrain noise. It would get really noisy above 2000rpm. If I shifted into 4th (700R4, OD), it all quieted down and was tolerable. I replaced pushrods and rocker arms and had the rockers adjusted several times; no improvement. Engine was quieter at idle but still had that sewing machine noise that increased with rpm.
I suspected that I had worn cam lobes/ failed lifter(s) so I plunged into a retro-roller conversion (having read and believed all the stories about poor dyno oil formulations and cam failures).
But, when I tore the cylinder heads down, I found my problem: worn valve guides (mostly on exhaust side) and recessed valve seats. I have DART heads and the bronze guides had worn so bad the valves were 'wobbly' in the guides. And, since the seats were hardened vs having steel inserts, the daily driving wore the hardened seats away.
I could have just had the $600 valve job done and stopped there; putting the conversion kit on the shelf but I had also had the machine shop install the dual springs with higher seat/open pressures than my weaker single springs that were tailored to my Energizer, flat tappet cam.
I would have the valves/cylinder heads looked at. You may find that is the problem (worn guides and seats).
I suspected that I had worn cam lobes/ failed lifter(s) so I plunged into a retro-roller conversion (having read and believed all the stories about poor dyno oil formulations and cam failures).
But, when I tore the cylinder heads down, I found my problem: worn valve guides (mostly on exhaust side) and recessed valve seats. I have DART heads and the bronze guides had worn so bad the valves were 'wobbly' in the guides. And, since the seats were hardened vs having steel inserts, the daily driving wore the hardened seats away.
I could have just had the $600 valve job done and stopped there; putting the conversion kit on the shelf but I had also had the machine shop install the dual springs with higher seat/open pressures than my weaker single springs that were tailored to my Energizer, flat tappet cam.
I would have the valves/cylinder heads looked at. You may find that is the problem (worn guides and seats).
Thread Starter
Instructor
Joined: Aug 2007
Posts: 140
Likes: 0
From: Erie Pa.
OK, i re adjusted the rockers, that may not be my problem, i got under the car when it was running and it sounds like the noise is from underneath, can I drop the oil pan with out pulling the engine?
Safety Car
Joined: Oct 2000
Posts: 3,593
Likes: 103
From: Southern Indiana
Safety Car
Joined: Jan 2009
Posts: 4,000
Likes: 299
From: New York
in my 72,( 350ci, 492 heads, mild cam) my rocker arms are crain roller tip rockers # p777,
I have adjusted my rockers but I still get a valve train noise, it doesn't sound like its hurting anything its just anoying. exsessive clatter is the only way i can explain.
is this normal with these roller tip rockers. previous owner said they are hydrolic lifters. Any input is welcome. thanks.
update, the noise sounds lower.
I have adjusted my rockers but I still get a valve train noise, it doesn't sound like its hurting anything its just anoying. exsessive clatter is the only way i can explain.
is this normal with these roller tip rockers. previous owner said they are hydrolic lifters. Any input is welcome. thanks.
update, the noise sounds lower.
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Team Owner
Joined: Oct 2004
Posts: 81,241
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From: altered state
St. Jude Donor '05
1/2-3/4 turn seemed to work better for me
used to do 1/4 turn and got a little noise never really stopped to figure if it would help noise or not. Many yrs ago so the memory is foggy
used to do 1/4 turn and got a little noise never really stopped to figure if it would help noise or not. Many yrs ago so the memory is foggy
Safety Car
Joined: Jan 2009
Posts: 4,000
Likes: 299
From: New York
The advantage to this when you have noises is your ability to see and here each valve .
Racer
Joined: Jul 2009
Posts: 344
Likes: 5
From: oak harbor wa
yes
BUT, you can you will need to drop at least one side of the steering i dropped the passenger side since it seemed easier, its a bit tight but do-able. It took me about 2 hours to drop everything replace gasket and re-install i suggest changing gasket to a http://www.summitracing.com/parts/fel-1885/overview/ oil pan gasket this was the only reason I dropped mine was a oil pan was leaking near front.
Last edited by lowes-yellow77; Apr 21, 2013 at 02:50 PM. Reason: extra
Melting Slicks
Joined: Dec 2009
Posts: 3,233
Likes: 657
From: Thunder Bay
My 383 has a retrofit roller cam and roller rockers and the valve train is much noisier than it was when I had the flat tappet cam and the conventional rockers. Near as I can tell, this is normal. And yeah, it sounds just like a sewing machine.