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Author Topic:   A few mo' ?'s
Eljojo
Member
posted February 22, 2004 08:18 AM
New hydraulic lifters. You can push the centers down easily. Will this change when the motor gets OP? Do I need to soak them in oil prior to installation? What is the difference (internally and function) when comparing a solid lifter and a hydraulic one?


wizzard
Member
posted February 22, 2004 09:24 AM
When you get the engine assembled run the primer to prime the engine with oil and slowly(with your hand and a wrench) turn you engine over to get oil in all of the lifters.


dan ferry
Member
posted February 22, 2004 06:34 PM
i reccomend reading posts on isky crane or someones site about setting hydraulic valve lash. you need to preload a hydraulic for it to work to its potential i do mine one cylinder at a time there are directions to do them a few at a time depending on crank position ive done it but prefer one at a time i guess i likke wasting my time lol. i think its posted as when exhaust starts to open adjust intake and when intake opens and then fully closes adjust exhaust turn push rod with finger untill feel starting to drag then go 1/2 turn.


dirtbuster
Member
posted February 22, 2004 08:17 PM
The plunger in it that you feel moving only takes up the slack in the valvetrain so that it runs at 0 lash. As soon as the lifter see oil pressure either running or priming it will automatically adjust itself to zero as long as there is a slight amount(the 0-1/2 turn) of preload on them. The solid lifter is just that solid there is no give to it. Think of it as a solid steel dowel with an oil passage in it. You have to physically adjust the valves to run the specified lash setting based on the cam because the lifter wont adjust itself. Thats why solids require more maintenance.
The drawback to the hyd is that it can work too well and overadjust and take up too much slack, especially at high rpm if the valves float and then it wont let the valve close and you lose cylinder pressure until you throttle back and let the lifter readjust. The anti pump up lifters are designed to run at 0 lash meaning you do not have to add the extra 1/2 turn when setting them. They will act more like a solid and wont over fill with oil and hold a valve open like a regular hyd would.
A hyd lifter doesnt actually pump oil to the top. Both solid and hyd lifters meter oil flow internally and then it is forced up through the pushrod and then to the rockers and valves. Sometimes people will run oil restrictors with solid lifters to limit oil flow but this restriction is before the lifters themselves. You cannot run restrictors with a hyd lifter becasue they require a good supply of oil to function properly but they dont necessarily pump it to the top end.


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