Re: Hydraulic Lifters and Valve Train Rattle

[Dave Casey <dcasey@xxxxxxxxxxxxx>]

Because more preload is effectively adding lift, so you're changing your 
camshaft profile.
That's the beauty of dyno tuning - you can tighten up the rockers and find 
out if you need a bigger cam.

Dave Casey

----- Original Message ----- 
From: "Gary Pavlovich" <glpavlovich@xxxxxxx>
To: <1962to1965mopars@xxxxxxxxxx>
Sent: Saturday, August 30, 2008 7:40 PM
Subject: Re: Hydraulic Lifters and Valve Train Rattle


> Don,
>
> Be careful with pre-loads.  We have found that being as little as 2-3 
> turns more than the correct pre-load cost us 60HP and 45ft.lbs. torque; 
> amazing what a seemingly slight difference to "us" is when it is a huge 
> change to the motor that deals in 100 thousands of tolerances.
>
> Gary Pavlovich
> ----- Original Message ----- 
> From: "Don Gallimore" <dongallimore@xxxxxxx>
> To: "Mailing List" <1962to1965mopars@xxxxxxxxxx>
> Sent: Saturday, August 30, 2008 5:15 PM
> Subject: Hydraulic Lifters and Valve Train Rattle
>
>
> > Earlier this year, I installed a new Comp Cams Hydraulic Lifter Cam with 
> > 440Source roller rockers. Now that I've run it a few miles (Carlisle and 
> > back), I adjusted the lifters and quickly change the oil and filter on my 
> > 440.
> >
> > When I started it, the oil pressure took a while to build up (need to 
> > fill the oil filter, I guess), but took a lot longer than I would have 
> > expected. Once I had oil pressure and started it, the rocker train was 
> > rattling pretty hard.  After putting an automotive stethoscope to the 
> > valve covers, found it was the right side valve train. So, shut down the 
> > motor, pulled the valve cover but found no problems.  Did no lash 
> > adjustment, just put the valve cover back on.
> >
> > No noise now?  Huh? Make any sense?
> >
> > While we're at it, Comp Cam said to adjust the rocker until it contacts 
> > the push rod then give it a half turn more for preload.  The studs are 
> > 20tpi so a half tune is 0.025 preload.  Sound right for preload?  I did 
> > notice when I pulled the valve covers for the above problem I could turn 
> > the pushrods on the closed valves by hand.
> >
> >  Akron Don
> >
> >
> > ----
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> >
> > '62 to '65 Mopar Clubhouse Discussion Guidelines:
>
>
> ----
> Please address private mail -- mail of interest to only one person --  
> directly to that person.  I.e., send parts/car transactions and 
> negotiations as well as other personal messages only to the intended 
> recipient, not to the Clubhouse public address. This practice will protect 
> your privacy, reduce the total volume of mail and fine tune the content 
> signal to Mopar topic.  Thanks!
>
> '62 to '65 Mopar Clubhouse Discussion Guidelines:


----
Please address private mail -- mail of interest to only one person -- directly to that person.  I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic.  Thanks!

'62 to '65 Mopar Clubhouse Discussion Guidelines:
http://www.1962to1965mopar.ornocar.org/mletiq.html.