Raymond Kitchen
Member
rebuild 1966 273 engine how do you adjust the valve lash while on engine stand and before start up on hydraulic lifters.
valve adj. on engine while on engine stand before. start up
- Thread starter Raymond Kitchen
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Get a Mopar Performance Valve Lash Adjustment Chart. Once you have oil pressure (priming w/o running) adjust the rockers until you can just spin the pushrods with your fingers. This will put you very close the final adjustment.
It's much easier for "ME" to adjust before they get oil pressure. That way you can actually feel the preload.
Professor Fate
Push the button, Max...
Since '66 still used solid lifters from the factory, I'll assume you've converted to hydraulics; and since you're asking about setting lash (actually, preload with hydraulics) I'll assume you retained the adjustable solid lifter rocker arms. I'll also assume you got custom pushrods of the correct length (solid and hydraulic lifters use different length).
Prime the engine, and then adjust the rockers so there is just zero clearance. Then give the adjusters another 1/4 turn.
Prime the engine, and then adjust the rockers so there is just zero clearance. Then give the adjusters another 1/4 turn.
That's a whole heap of assumin. lol
Professor Fate
Push the button, Max...
Sometimes ya gotta work with the info you've been given...
Yup. We gots no choice. lolSometimes ya gotta work with the info you've been given...
Why it is important for posters to post ALL the information.
Kendog 170
Let the boy go !
You can read this.
How to Set Valve Lash
This is what I do.
Valve Lash Adjustment
Starting at Number 1 cylinder, rotate the engine until the exhaust rocker just starts to open the exhaust valve. Set the valve lash on the intake rocker at this time. Continue rotating the assembly and stop when the intake rocker starts returning from full lift. Now the lash on the exhaust rocker can now be set. Continue this procedure for the remaining cylinders following the engine’s firing order.
If setting preload for Hydraulic lifters remove up and down play on pushrod then add ¼ to ½ turn of preload. Some people say tighten until you it gets hard to turn the pushrod then set preload I don’t agree with this method as the lifter may not be pumped up. JMO. If the motor was just running then yes this works.
This method works on almost any flat tappet engine
How to Set Valve Lash
This is what I do.
Valve Lash Adjustment
Starting at Number 1 cylinder, rotate the engine until the exhaust rocker just starts to open the exhaust valve. Set the valve lash on the intake rocker at this time. Continue rotating the assembly and stop when the intake rocker starts returning from full lift. Now the lash on the exhaust rocker can now be set. Continue this procedure for the remaining cylinders following the engine’s firing order.
If setting preload for Hydraulic lifters remove up and down play on pushrod then add ¼ to ½ turn of preload. Some people say tighten until you it gets hard to turn the pushrod then set preload I don’t agree with this method as the lifter may not be pumped up. JMO. If the motor was just running then yes this works.
This method works on almost any flat tappet engine
Need this printed poster sized and laminated so I can hang it on the wall.... lol
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I have the Mopar decal and it's on the firewall of the car.
All suggestions will work, I would have done this before the intake was installed, no oil pressure. Also, find the travel of the tappet with his set up and then get in the middle. The decal worked for me until I measured the timing tape around my balancer, an indicated balancer would be okay. So I do the rocker arm method now.
Kendog 170
Let the boy go !
I too have laminated one in the trunk of each dart and one in my toolbox.
I'm curious, everything here says 1/4 to 1/2 turn preload. The machine shop set mine at 1/2 turn (340 TA heads and rockers), but both the DC Engine book and the FSM say 1&1/2 turns... Can anybody shed light on this?
Well, it works good for mild to moderate camshafts, but the bigger they get, the more skewed that chart is.
Yeah, 1 to 1.5 turns down is too tight, IMO. I never go by the number of turns. I throw that out the window. I manually MEASURE preload.
Get out or upload the Factory Service Manual and follow the procedure.
Service Manuals – MyMopar
Service Manuals – MyMopar
I agree 100% with that recommendation using stock camshafts, but with performance grinds, the last thing you want is too much preload and that's what you'll end up with following the FSM on a performance grind.
Professor Fate
Push the button, Max...
The FSM doesn't cover hydraulic lifter preload when using solid lifter adjustable rockers. The '70 TA book is as close as you'll get in that regard. Otherwise the FSMs won't mention it since the factory hydraulics were non-adjustable.
The Hemi instructions in the FSM are based on hydraulic lifters and adjustable ductile iron rocker arms and the instructions call for 1&1/2 turns in. The Direct Connection Engine book has instructions based on using 273 factory adjustable rockers on any LA small block and it calls for the same thing, but everybody I know that uses an adjustable hydraulic system does 1/2 turn with good results. I'm just wondering why the discrepancy...
Just did mine last night.
Solid roller?
Yes.
Professor Fate
Push the button, Max...
Once you start throwing aftermarket parts into the mix, that's the best way to do it. Considerations like lifter manufacturer, use of aluminum heads (which can "grow" when hot), etc. can affect the amount of preload you want to dial in.
For example, Rhoads publishes a good set of guidelines for initial set-up that illustrate the procedure and reasoning that applies to most lifter brands.
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